Prefab bridges for Georgia city and county roads [2016]

GEORGIA DOT RESEARCH PROJECT 14-10 FINAL REPORT
PREFAB BRIDGES FOR GEORGIA CITY AND COUNTY ROADS
OFFICE OF RESEARCH 15 KENNEDY DRIVE
FOREST PARK, GA 30297-2534

1.Report No.: FHWA-GA-16-1410

2. Government Accession No.: 3. Recipient's Catalog No.:

4. Title and Subtitle: Prefab Bridges for Georgia City and County Roads

5. Report Date: February 2016
6. Performing Organization Code:

7. Author(s): Junsuk Kang, Mike Jackson, Marcel Maghiar, Gustavo Maldonado, Peter Rogers

8. Performing Organ. Report No.:

9. Performing Organization Name and Address: Department of Civil Engineering and Construction Management Georgia Southern University PO Box 8077 Statesboro, GA 30460-8077
12. Sponsoring Agency Name and Address: Georgia Department of Transportation Office of Research 15 Kennedy Drive Forest Park, GA 30297-2534

10. Work Unit No.:
11. Contract or Grant No.: RP 14-10/0012919
13. Type of Report and Period Covered: Final; December 2014-February 2016
14. Sponsoring Agency Code:

15. Supplementary Notes: Prepared in cooperation with the U.S. Department of Transportation, Federal Highway Administration. 16. Abstract:
The objective of this study was to develop and deliver a toolkit to help local governments (LGs) in Georgia select and construct bridges using prefabricated modular systems with 40-, 60-, and 80-foot spans. The components of the proposed accelerated bridge construction (ABC) toolkit address: 1) decision-making; 2) design; 3) construction; 4) risk analysis; and 5) cost estimation. It will be an extensive, convenient source of the latest guidelines for ABC applications. It is not intended for developing final design and construction plans but as a source of information to help decision-makers and owners develop an initial design, estimate the material and construction costs, and determine when and where ABC will be most beneficial. It will provide guidelines to assist local governments and third-party designers using GDOT design standards for ABC. With repeated implementation, ABC options will become even more economical and efficient.

17. Key Words: Accelerated bridge construction; Concrete girder; Design; Prefabricated bridge; Steel girder; Toolkit

18. Distribution Statement:

19. Security Classification (of this report):
Unclassified

20. Security Classification (of this page):
Unclassified

21. Number of Pages: 425

22. Price:

Form DOT 1700.7 (8-69)

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GDOT Research Project No. 14-10
Final Report
PREFAB BRIDGES FOR GEORGIA CITY AND COUNTY ROADS
Submitted by
Junsuk Kang, Ph.D., Assistant Professor Mike Jackson, Ph.D., P.E., Professor and Chair
Marcel Maghiar, Ph.D., Assistant Professor Gustavo Maldonado, Ph.D., P.E., Associate Professor
Peter Rogers, Ph.D., P.E., Associate Professor
Department of Civil Engineering and Construction Management Georgia Southern University
P.O. Box 8077, Statesboro, GA 30460-8077
Contract with Georgia Department of Transportation
In cooperation with U.S. Department of Transportation Federal Highway Administration
February, 2016
The contents of this report reflect the views of the authors who are responsible for the facts and the accuracy of the data presented herein. The contents do not necessarily reflect the official views or policies of the Georgia Department of Transportation or the Federal Highway Administration. This report does not constitute a standard, specification, or regulation.
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ACKNOWLEDGMENTS The authors thank the Georgia Department of Transportation (GDOT) for its strong support and invaluable input. The work conducted was sponsored by the Office of Research o f GDOT ( Research Project 14-10). The authors particularly acknowledge the contribution of Gretel Sims, Benjamin Rabun, Binh Bui, and David Jared. The Transportation Research Board kindly granted permission to reproduce the article "Innovative Bridge Designs for Rapid Renewal: SHRP 2 Project Develops and Demonstrates a Toolkit" by Bala Sivakumar in our accelerated bridge construction (ABC) Toolkit for GA, modifying the Mathcad examples from the original SHRP 2 Mathcad files. Professor Emeritus Dr. Noyan Turkkan at the University of Montana generously granted us permission to use the qBridge software, a Mathcadbased code, in this project.
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TABLE OF CONTENTS
ACKNOWLEDGMENTS ......................................................................................................................... iv LIST OF TABLES ...................................................................................................................................viii LIST OF FIGURES ................................................................................................................................... ix EXECUTIVE SUMMARY ........................................................................................................................ x CHAPTER 1. INTRODUCTION AND RESEARCH APPROACH...................................................... 1 CHAPTER 2. SURVEYS ........................................................................................................................... 4
2.1 OVERVIEW OF DOT SURVEYS .................................................................................................. 4 2.1.1 Results ......................................................................................................................................... 4 2.1.2 Impediments ............................................................................................................................. 11
2.2 INDUSTRIAL SURVEYS .............................................................................................................. 16
2.3 SUMMARY ..................................................................................................................................... 17 CHAPTER 3. ABC DECISION-MAKING TOOLS ............................................................................. 18 CHAPTER 4. ABC DESIGN CONCEPTS ............................................................................................ 19
4.1 MODULAR SUPERSTRUCTURE SYSTEMS ........................................................................... 19 4.1.1 Decked Steel Stringer System ................................................................................................. 19 4.1.2 Composite Steel Tub Girder System ...................................................................................... 20 4.1.3 Precast Concrete Deck Bulb Tee and Double Tee................................................................. 21 4.1.4 Pre-Topped Trapezoidal Concrete Tub Beams..................................................................... 22 4.1.5 Full-Depth Precast Concrete Deck Systems .......................................................................... 22 4.1.6 Ultra-High Performance Concrete (UHPC) Superstructures.............................................. 23 4.1.7 Connections between Modules ................................................................................................ 24 4.1.8 Summary of Design Considerations for Modular Superstructures..................................... 24
4.2 MODULAR SUBSTRUCTURE SYSTEMS................................................................................. 25 4.2.1 Integral and Semi-Integral Abutments .................................................................................. 26 4.2.2 Jointless Construction.............................................................................................................. 26 4.2.3 Precast Abutments and Wingwalls......................................................................................... 27 4.2.4 Connections .............................................................................................................................. 28 4.2.5 Precast Complete Piers ............................................................................................................ 28 4.2.6 Hybrid Drilled Shaft/Micropile Foundation Systems ........................................................... 29 4.2.7 Steel or Fiber-Reinforced Polymer (FRP) Jacket System for Existing Column ................ 29
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CHAPTER 5. RISK ANALYSIS ............................................................................................................. 31 5.1 THE ROLE OF RISK IN CULVERT AND BRIDGE DESIGN ................................................ 31 5.2 CHOOSING BETWEEN A CULVERT AND A BRIDGE CROSSING ................................... 31 5.3 SELECTING A CULVERT TYPE AND SIZE............................................................................ 32 5.4 PROCESS FOR SIZING AND DESIGNING CULVERTS........................................................ 34 5.5 PROCESS FOR SIZING CULVERTS AND REQUIRED BRIDGE OPENINGS .................. 35 5.6 BRIDGE FOUNDATION INVESTIGATION AND SCOUR .................................................... 45
CHAPTER 6. CONCEPTUAL COST ESTIMATES ............................................................................ 47 6.1 CONTRACTOR COST CONCERNS .......................................................................................... 47 6.2 COST OPTIONS............................................................................................................................. 48 6.3 ROAD USER COSTS ..................................................................................................................... 48 6.4 SAFETY COSTS............................................................................................................................. 48 6.5 LIFE CYCLE COST ANALYSIS ................................................................................................. 48 6.6 COST ACCOUNTING OPTIONS ................................................................................................ 48
CHAPTER 7. TYPICAL CONSTRUCTION PRACTICES ................................................................ 50 7.1 ABC CONSTRUCTION CONCEPTS .......................................................................................... 50 7.1.1 Prefabricated Spread Footings ............................................................................................... 50 7.1.2 Precast Pile Cap Footings........................................................................................................ 51 7.1.3 Modular Block Systems ........................................................................................................... 51 7.1.4 Geosynthetic Reinforced Soil Integrated Bridge System (GRS-IBS) .................................. 52 7.1.5 Expanded Polystyrene (EPS) Geofoam for Rapid Embankment Construction................. 53 7.1.6 Abutments or End-Bents ......................................................................................................... 54 7.1.7 Prefabricated Superstructure Elements ................................................................................ 54 7.1.8 Materials for Prefabricated Bridge Elements ....................................................................... 54 7.2 APPLICATION EXAMPLES OF ABC CONSTRUCTION TECHNOLOGIES .................... 56 7.2.1 Rehabilitation of Existing Bridges .......................................................................................... 56 7.2.2 Deck Replacement.................................................................................................................... 56 7.2.3 Superstructure Replacement .................................................................................................. 57 7.2.4 Substructure Replacement ...................................................................................................... 57 7.2.5 Replacement of Existing Bridges and New Bridges .............................................................. 58
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7.2.6 Staging....................................................................................................................................... 58 7.2.7 Full Closure and New Construction ....................................................................................... 58 7.3 ABC CONSTRUCTION TECHNOLOGIES ............................................................................... 58 7.3.1 Above-Deck Driven Carrier (ADDC)..................................................................................... 59 7.3.2 Launched Temporary Truss Bridge....................................................................................... 59 7.3.3 Self-Propelled Modular Transports (SPMTs) ....................................................................... 59 7.3.4 Launching and Lateral Shifting.............................................................................................. 59 CHAPTER 8. ABC TOOLKIT................................................................................................................ 61 CHAPTER 9. SUMMARY AND CONCLUSIONS............................................................................... 63 SELECTED BIBLIOGRAPHY............................................................................................................... 64 LIST OF USEFUL ABC WEBSITES ..................................................................................................... 68 APPENDICES Appendix A. Survey Results Appendix B. ABC Sample Design Examples and Flowcharts (using Mathcad) Appendix C. ABC Construction Practice Flowcharts Appendix D. Risk Analysis Examples and Interactive Flowchart Appendix E. Conceptual Cost Estimates Examples Appendix F. ABC Decision-Making Tools Appendix G. ABC Toolkit Template Appendix H. Design Aides (using Mathcad) Appendix I. Implementation Plan
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LIST OF TABLES Table 5.1. Regression Equations for Estimating Peak Flow in Rural Ungauged Areas that are Entirely
Within One Hydrologic Region (USGS, 2009) ........................................................................ 37 Table 5.2. Runoff Coefficients (C) for the Rational Method (GDOT, 2014)............................................. 39 Table 5.3. Frequency Adjustment Factors for Rational Method (Georgia Stormwater Management
Manual, 2001) ........................................................................................................................... 40 Table 5.4. Rainfall Intensity Information for One Hour Storms Across Georgia (GSMM, 2001) ........... 41 Table 5.5. Pipe Culvert Sizing Table (Sizes Common for Corrugated Steel Pipe) .................................... 44 Table 5.6. Box Culvert Sizing Table (American Concrete Pipe Association, 2015) ................................. 45 Table 5.7. Equivalent Capacities for Multi-barrel Pipe Culverts ............................................................... 45 Table 8.1. Comparison of the SHRP2 R04 ABC toolkit and the proposed toolkit .................................... 61
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LIST OF FIGURES
Figure 4.1. Decked Steel Stringer System. (a) Steel grid open or filled with concrete (photo: D.S. Brown Co.). (b) Full-depth precast deck panels with and without longitudinal post-tensioning (FHWA, 2015). (c) Partial-depth precast deck panels (photo: Keegan Precast on project in UK by contractor Laing O'Roruke). ....................................................................................... 20
Figure 4.2. (a) Steel tub girder (photo: Greg Price, DHS Discussion Forum). (b) Concrete tub girder (photo: StressCon Industries, Inc., website). (c) Open trapezoidal composite box girder SteelConstruction.info)............................................................................................................ 20
Figure 4.3. Composite Steel Tub Girder (SHRP, 2014)............................................................................. 21 Figure 4.4. (a) Adjacent deck bulb tee beams (FHWA, 2015). (b) Adjacent double tee beams (FHWA,
2015). (c) NEXT beam (drawing on High Steel Structures LLC website). ............................ 21 Figure 4.5. Cross Sections of Pre-topped, Trapezoidal, Concrete U Beams (SHRP2, 2014). ................... 22 Figure 4.6. Full-depth Precast Concrete Deck System (SHRP2, 2014). .................................................... 23 Figure 4.7. (a) Precast modular abutment systems (SHRP2, 2014). (b) Precast complete pier system
(FHWA, 2015). (c) Hybrid drilled shaft/micropile foundation (SHRP2, 2014). .................... 26 Figure 4.8. (a) and (b) Precast modular abutment systems. (c) Precast wingwall (SHRP2, 2014)............ 28 Figure 4.9. Precast Concrete Pier (SHARP2, 2014). ................................................................................. 29 Figure 4.10. (a) Steel/FRP jacket concept (SHRP2, 2014). (b) Steel jacketed bridge column (Nelson,
2012). (c) FRP jackets in several bridge columns (Buccola, 2011). ....................................... 30 Figure 5.1. Common Culvert Shapes (Purdue University, 2005). ............................................................. 32 Figure 5.2. Pipe (a), Box (b), and Arch (c) Culverts (Cranberry Township, American Concrete Industries,
and Contech, 2015).................................................................................................................. 33 Figure 5.3. Bridge Culvert (Contech, 2015). ............................................................................................. 34 Figure 5.4. Culvert Cross Section showing Headwater and Tailwater Levels (Purdue University, 2005).35 Figure 5.5. Example of a Delineated Watershed Boundary (Natural Resources Conservation Service,
2014)........................................................................................................................................ 35 Figure 5.6. Example Hydrograph............................................................................................................... 36 Figure 5.7. Map of the Georgia Flood Frequency Regions (USGS, 2008). ............................................... 37 Figure 5.8. Location of the 16 Sites Containing Rainfall Intensity Information (GSMM, 2001).............. 40 Figure 5.9. Georgia Rainfall Intensity Data for a One Hour Storm, 50 Year Return Period (NOAA,
2015)........................................................................................................................................ 42 Figure 5.10. Georgia Rainfall Intensity Data for a One Hour Storm, 100 Year Return Period (NOAA,
2015)........................................................................................................................................ 43 Figure 7.1. Example of Precast Spread Footing Plan and Section (MassDOT, 2013)............................... 51 Figure 7.2. Modular Block Systems (photo: Redi-Rock.com and ReinforcedEarth.com)......................... 52 Figure 7.3. Typical GRS-IBS Cross Section at the Bridge Abutment (Adams et. al, 2012)...................... 53 Figure 7.4. (a) Bridge abutment with geofoam backfill. (b) EPS geofoam in embankment fill. (c) EPS
geofoam for embankment widening (Bartlett et. al., 2000)..................................................... 53 Figure 7.5. (a) Location of abutments at each end of the bridge (image from Benchmark Hunting Wiki).
(b) Integral abutment placed behind a mechanically stabilized earth (MSE) wall (Hailat, 2014). (c) Partial precast end abutment (Hailat, 2014)............................................................ 54 Figure 7.6. Prefabricated Superstructure Elements (SHRP2, 2014). ......................................................... 54 Figure 7.7. Self-propelled Modular Transporters (AASHTO, 2006)......................................................... 57
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EXECUTIVE SUMMARY
Accelerated bridge construction (ABC) differs from conventional cast-in-place methods in that all the members are prefabricated then lifted into place and assembled onsite. As a result of increased interest and use of ABC in Georgia, the Georgia Department of Transportation (GDOT) funded a research project aimed at introducing ABC design and construction to Georgia cities and counties through the use of a toolkit. The research focused specifically on short span bridges for span lengths of 40, 60, and 80 ft. The toolkit is not intended to be used for developing a final design, but rather as an informational source that can help decision makers develop an initial design, estimate the material and construction costs, and determine when and where ABC is most beneficial. This study presents the process used in developing the toolkit and its primary features.
The first phase of the project involved the creation and completion of a survey which was distributed to several state DOTs. It contained questions regarding the organization's experience with ABC, the level of acceptance of ABC techniques in their state, the number of completed projects in recent years, impediments to the use of ABC techniques, and the ongoing research on ABC topics in the entity's state.
The toolkit itself contains construction, design, risk analysis, and cost estimate components. The construction guidelines will encompass most steps in the construction process from the foundation to the paving of the deck. It will also outline the construction process of the offsite prefabrication area, transportation of elements, and setting of the prefabricated bridge elements. The design component of the toolkit will provide design concepts, user friendly pre-design examples, and interactive design flowcharts with design aides such as Mathcad, which will allow readers, such as Georgia city and county engineers, to easily follow the extensive procedures involved in ABC bridge construction. Both steel and concrete girder design examples were developed and modified to allow for easy understanding using GDOT standard criteria for highway bridges, information obtained from a design example created by the Federal Highway Association (FHWA), and the latest AASHTO LRFD Bridge Design Specifications, 6th ed. (2012). The base design examples were taken from "Innovative Bridge Designs for Rapid Renewal" (SHRP2, 2013).
In terms of risk analysis, the risk assessment components of the toolkit focused on the evaluation of the bridge's ability to convey the design and base floods without causing significant damage to the roadway, stream, bridge itself, and other property. The guidelines with an interactive flowchart will be created to assist the potential designer in the collection of the hydrologic data needed to determine the peak discharges for different design year floods and perform a hydraulic analysis. The cost estimate component will provide examples of cost comparisons between corresponding Federal and State requirements to guide local governments in their cost estimation activity.
The proposed ABC toolkit will provide guidelines to assist local governments and third-party designers in employing GDOT design standards for accelerated-built bridges. In the future, sufficient ABC experience in GA will lead to contractor acceptance as well as to savings in schedules and costs, which could diminish the initial additional costs with a consistent and repeated application of ABC practices.
Key Words: Accelerated bridge construction (ABC); Concrete girder; Design; Steel girder, Toolkit.
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CHAPTER 1. INTRODUCTION AND RESEARCH APPROACH
Accelerated bridge construction (ABC) encompasses the techniques used in the prefabrication of bridge sections to decrease the closure time required to construct or renovate a bridge. From the Federal Highway Administration (FHWA) website, the definition of ABC is a bridge construction that uses innovative planning, design, materials, and construction methods in a safe and cost effective manner to reduce the onsite construction time that occurs when building new bridges or replacing and rehabilitating existing bridges. In other words, ABC is "building the bridge first before setting up the traffic control cones, and then move it quickly into places, like in hours or a weekend." (Mistry 2008). As a result of increased interest and use of ABC in Georgia, the Georgia Department of Transportation (GDOT) funded a research project aimed at introducing ABC design and construction to Georgia cities and counties through the use of a toolkit. This study focuses on short span bridges, between 40 and 80 feet, for the state of Georgia. Special attention was given to various areas of ABC, generally regarding design, constructability, and risk analysis, and specifically regarding the use of concrete and steel girders, concrete-decked steel girders, prestressed concrete, as well as cost efficiency, lessons learned reports from other states' completed projects, and industry surveys. Several specific case studies were also conducted to evaluate the performance and design-to-finish process of a bridge which utilizes prefabricated modular systems.
ABC techniques have been performed in the past and are currently being investigated for more extensive use. Garver, an engineering consultancy out of Arkansas, details the process of a lateral slide, a bridge sliding technique used to replace a bridge superstructure. There is no one ABC technique in use in the United States. Instead, there is a family of ABC construction technologies that are in use that cover the majority of ABC projects. In construction, the foundation and wall element technologies are in the early stages of deployment, while others such as modular superstructure systems are mature and in use on a regular basis. Benefits to employing ABC techniques include:
ABC improves: Site constructability; Total project delivery time; Material quality and product durability; and Work-zone safety for the commuters and contractor personnel.
ABC reduces: Traffic impacts; Onsite construction time; and Weather-related time delays.
ABC can minimize: Environmental impacts; Impacts to existing roadway alignment; and Utility relocations and right of way take.
` Commonly, ABC has been employed to reduce the traffic impact since the safety and flow of
public travel and the flow of transportation directly correspond to the onsite construction flow of the
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activities. There are other common and equally viable reasons to use ABC, which range from site constructability issues to time management issues.
Conventional bridge construction, commonly referred to as cast-in-place (CIP) methods, is construction that does not focus on the reduction of onsite construction time. Conventional construction methods involve onsite activities that are time consuming and weather dependent. Conventional construction includes onsite installation of bridge substructures and superstructures, placing reinforcing steel, and concrete placement, followed by concrete curing.
Effectiveness of ABC is determined by two factors: onsite construction time and mobility impact time. Onsite construction time is the period of time from when a contractor alters the project site location until all construction related activity is removed. Some examples involved include maintenance of traffic items, construction materials on site, equipment, and workforce. Mobility impact time is any period of time the traffic flow of the commuters is reduced due to onsite construction activities. The fewer amount of disruptions, the better and least expensive.
The use of prefabricated bridge elements and systems (PBES) is one of the most crucial strategies employed to meet the objectives of ABC. PBES are structural components of a bridge that are built offsite. These elements help reduce the onsite construction time and commuter impact time that occurs from conventional construction methods. Combining PBES with the "Fast Track Contracting" method can create a high-performance and fast paced construction project. Components of PBES include, but are not limited to:
Precast footings; Precast wing walls; Precast pile foundations; Prefabricated caps and footings; and Prefabricated steel/concrete girder beams.
The first phase of the project involved the creation and completion of a survey which was distributed to several state DOTs. It contained questions regarding the organization's experience with ABC, the level of acceptance of ABC techniques in their state, the number of completed projects in recent years, impediments to the use of ABC techniques, and the ongoing research on ABC topics in the entity's state.
The primary objective of this study was to develop and deliver a toolkit for accelerated selection and construction of bridges in place using prefabricated modular systems with 40, 60, and 80 feet span lengths for local governments (LGs) in Georgia. The proposed toolkit itself contains construction, design, risk analysis, cost estimate components, and decision-making tools. The construction guidelines will encompass most steps in the construction process from the foundation to the paving of the deck. It will also outline the construction process of the offsite prefabrication area, transportation of elements, and setting of the prefabricated bridge elements. The design component of the toolkit will provide user friendly pre-design examples and interactive design flowcharts with design aides such as Mathcad, which will allow readers, such as Georgia city and county engineers, to easily follow the extensive procedures involved in ABC bridge construction. Both steel and concrete girder design examples were developed and modified to allow for easy understanding using GDOT standard criteria for highway bridges, information obtained from a design example created by the Federal Highway Association, and the latest AASHTO LRFD Bridge Design Specifications, 6th ed. (2012). The base design examples were taken from the SHRP 2 document, "Innovative Bridge Designs for Rapid Renewal" (SHRP2 2013). In terms of risk analysis, the risk assessment components of the toolkit focused on the evaluation of the bridge's ability to convey
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the design and base floods without causing significant damage to the roadway, stream, bridge itself, and other property. The guidelines with an interactive flowchart will be created to assist the potential designer in the collection of the hydrologic data needed to determine the peak discharges for different design year floods and perform a hydraulic analysis. The cost estimate component will provide examples of cost comparisons between corresponding Federal and State requirements and survey other state DOTs regarding their conceptual cost estimates.
The toolkit is not intended to be used for developing final design and construction, but rather as an informational source that can help decision makers develop an initial design, estimate the material and construction costs, and determine when and where ABC is most beneficial. The proposed ABC toolkit will provide guidelines to assist LGs and third-party designers in employing GDOT design standards for accelerated-built bridges. With the sufficient and repeated application, ABC option can become more economical and efficient.
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CHAPTER 2. SURVEYS
2.1 OVERVIEW OF DOT SURVEYS
The survey was submitted to various agencies in order to inquire as to their experience with ABC. The survey was used to evaluate their successes and to find out what worked, as well as to evaluate their failures to find out what did not. This survey consisted of questions which gauged the experience of bridge owners. Their responses are noted in our research, and state DOTs from all 50 states were contacted regarding their own ABC experiences via a more generalized 7-question survey (taken from SHRP2 2013) by the Georgia Southern ABC Research team. They were asked questions specifically regarding:
The amount of experience they have had with ABC in recent years and how many projects they have completed.
The general level of acceptance of ABC in their state. Which agency generally engineers the projects to have components of ABC. Which impediments, if any, are keeping these agencies from opting to use ABC techniques as
opposed to traditional methods. The availability of standardized elements and the benefit thereof. The condition of ongoing or completed projects. Current research regarding ABC.
Results from our surveys were obtained from 45 of the 50 states and are summarized using tables and U.S. maps in Appendix B. With the exception of Arkansas, Nebraska, and North Dakota, all indicated states have completed ABC projects in recent years and ABC has become standard in Utah and Colorado. The following section briefly presents the level and status of ABC application for each state:
2.1.1 Results Alabama: The Alabama DOT (ALDOT) has completed one project in the past 5 years. The level of acceptance of ABC within the state is low and contractors are doubtful about its use for typical bridges. However, they think ABC could be successful for long structures that require substantial repetition of elements. Alabama is currently involved in the research and testing of four systems of rapid deck replacement on structures in the northern region of the state.
Alaska: The Alaska DOT & Public Facilities (ADOT&PF) has completed several projects in recent years, and the support for ABC is moderate within the state. Projects completed recently use decked bulbtee girders so that construction is faster and a deck does not need to be cast in place. They have also used precast pier cap beams, full depth deck planks, and other prefabricated bridge elements. Projects are engineered to employ ABC, but contractors on occasion have opted to use ABC. Standardization would help encourage ABC, but training and education would probably help more. Most recently, ADOT&PF has completed research on an all-steel bridge pier system that can be quickly constructed in remote locations. It is reported to have good seismic performance but may not be acceptable in the highest seismic regions.
Arizona: The Arizona DOT (ADOT) has completed one project using PBES connections. ABC is valued and there are plans to use it on future projects. The decision to use is sometimes left up to the contractor,
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but projects are often designed to utilize ABC. Standardization would help the decision making process of whether or not to use ABC. Currently, ADOT is in the planning stages of a bridge replacement project that will use a geosynthetic reinforced soil integrated bridge system (GRS-IBS) abutment and a bridge slide. Research on Ultra-High Performance Concrete (UHPC) connections is in progress.
Arkansas: The Arkansas State Highway and Transportation Department (AHTD) has no active ABC program. Their perception is that ABC projects will be more expensive and thus counter to their desire for cost savings.
California: The California DOT (Caltrans) described several recent projects in which various ABC methods were employed and indicated that meaningful incentives / disincentives greatly motivated contractors. For example, seismic concerns limit their use of precast pier elements, and they are concerned about long-term durability and the ability to balance the higher costs of ABC projects against user cost-savings.
Colorado: The Colorado Department of Transportation (CDOT) has completed a wide array of projects using ABC, including 73 bridge projects and culverts as of March 2015. The level of acceptance is clearly high. Most bridge projects are designed to employ ABC, but for some design-build projects, the decision is left up to the contractor. Standardization is believed essential; ABC is standard in Colorado and considered on every project, although complex bridge projects will always require a certain level of customization. CDOT is not currently conducting research on ABC.
Connecticut: None reported
Delaware: The Delaware DOT (DelDOT) has completed fewer than 10 projects in the past 5 years. They were all engineered to employ ABC techniques, so acceptance of innovation is generally good. Projects have used precast elements, but no research on ABC is ongoing.
Florida: The Florida Department of Transportation (FDOT) has conducted many ABC projects in recent years, and though it is not a standard practice, it is considered in every project. Florida has access to standardized elements, but contractors tend to avoid subcontracting work to broadcasters because they make their profit from placing steel and concrete. FDOT does not mandate the use of ABC but leaves the decision up to the contractor. Each bridge project has performance specifications that contractors must meet, and because contractors are given more responsibility with ABC, uncertainties about their methods persist.
Georgia: GDOT has completed one ABC project in recent years. The decision to use ABC techniques is left up to the contractor, and GDOT does consider the standardization of prefabricated elements a way to lower costs associated with ABC. GDOT is currently preparing their own prefabricated bridge toolkit to expedite the application of ABC and other prefabricated bridge technologies in GA city and county roads.
Hawaii: The Hawaii DOT (HDOT) has been using ABC concepts since precast-prestressed concrete elements were introduced in around 1959. However, based on current definitions, it started in 2001 with the use of adjacent slab beams made of precast-prestressed concrete. Hawaii has completed over 20
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projects since 2001. The level of acceptance is very high, and some ABC projects proved less expensive than CIP projects. Government incentives would encourage further use of ABC in the state, and though standardized elements are available, ABC is only used when it proves economically beneficial. In the field, it saves contractors money in forming, shoring, and stressing tendons or prestressing strands. Time is saved when these elements are prefabricated while other fieldwork is being performed.
Idaho: None reported.
Illinois: The Illinois Department of Transportation (IDOT) has completed several projects using ABC methods in recent years. Bridge projects undergo a "Bridge Planning State", during which ABC is evaluated based on site needs and cost-versus-benefit analyses. Standardized elements would help to curtail ABC costs.
Indiana: The Indiana DOT (INDOT) has completed two ABC projects in recent years; they used the bridge-slide technique. Projects are designed to use ABC techniques, and standards would make ABC more efficient.
Iowa: The Iowa DOT (IOWADOT) has extensive experience with ABC and has completed approximately eleven ABC projects in recent years. Research focusing on substructure is under way with funding from the Iowa Highway Research Board. Acceptance in the state is good, and projects are designed to use ABC.
Kansas: The Kansas DOT (KDOT) used prefabricated materials, including precast concrete girders and deck panels, even before FHWA's "Every Day Counts" initiative. Its first official ABC project was designed in August 2014 and let in November 2014. It is modeled after Iowa's Keg Creek bridge project and used a pre-installed foundation; precast columns, abutments, and pier caps; a conventional weathering steel rolled beam superstructure; and precast, full-depth segmental deck sections post-tensioned together. Bridges are designed to employ ABC concepts. Contractors can also use ABC with KDOT permission, and this would normally happen after the project is let. Kansas law prohibits delivery methods other than design-bid-build. The 2014 project attracted only one bid because of its high price. It will be relet in June 2015.
Kentucky: None reported.
Louisiana: The Louisiana Department of Transportation and Development (LDOTD) has extensive experience with ABC methods, specifically using precast elements, such as span and cap segments, and float-out, float-in construction to erect long-span bridges over its many waterways. It has also used precast flat slab bridges for federal highway system projects. LDOTD reports that though these bridges do not provide the service life of their CIP counterparts, they are easier to construct in remote areas. While the state's soil conditions preclude precasting longer girder spans, standardization would be possible for shorter spans. Contractors often request that crane mats be used on the top of the structure, so a standard element that accounts for crane loads would be ideal. The department plans to continue using ABC techniques in the future.
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Maine: The Maine DOT (MaineDOT) has completed several ABC projects in recent years. Acceptance is high, and standardization of elements might help lower precasting costs by encouraging fabricators to invest in standard forms for bridge elements.
Maryland: The Maryland DOT (MDOT) has completed several projects using ABC techniques in recent years and has experienced no significant problems. The major bar to further use is the lack of technique testings.
Massachusetts: The Massachusetts DOT (MassDOT) has not completed any ABC projects but is interested in implementing pilot projects to become familiar with techniques. Standardized elements would be useful in reducing the need to develop custom details, and unfamiliarity could be offset by learning about standardized elements that have been successful in other locations.
Michigan: The Michigan DOT (MDOT) has some experience with ABC methods; it completed projects designed to use ABC concepts and projects accelerated by the contractor. Standardization could make ABC methods more accessible to designers and would help contractors gain meaningful experience, helping to lower costs and improving quality in the long run.
Minnesota: The Minnesota Department of Transportation (MnDOT) has completed approximately 20 projects using ABC techniques. Acceptance is good. In MnDOT design-bid-build projects, the contractor proposes ABC, and use is generally approved. Value Engineering (VE) proposals are also considered during construction. Standardization of elements would help but not substantially. While UHPC addresses precast connection issue, it is expensive and requires a high level of contractor and supplier expertise. MnDOT is participating in a National Cooperative Highway Research Program (NCHRP) project to define tolerances for precast elements and design criteria for lateral slides and self-propelled modular transport (SPMT) moves.
Mississippi: ABC is only applied selectively at this point, reserved for emergency reconstruction or projects with special conditions, such as emergency access or site constraints. MDOT senior management must be convinced of the advantages of acceleration and would appreciate having a catalog of ideas to choose from rather than prescriptive standards when trying to decide whether or how to pursue an ABC project.
Missouri: The Missouri DOT (MoDOT) cited various examples of recent ABC deployment. Although these projects alleviate traffic constraints, they are much more expensive than conventional approaches and must be used judiciously.
Montana: The Montana DOT (MDT) has completed only one ABC project: the Highway 89 Pondera County Marias River Crossing, which used a GRS-IBS abutment system. The design included a wall radial edge as opposed to the more common straight edge design and was an on-site adjustment. The block required for the abutments was made to order, and the manufacturer was not equipped to produce rounded-edge blocks. MDT is still conducting research on GRS-IBS systems.
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Nebraska: The Nebraska Department of Roads (NDOR) has not used ABC methods on any completed projects but completed its first GRS-IBS bridge with folded plate girders for a local agency in Boone County, finishing the project within 30 days in 2014. The GRS abutment was built in 15 days, including excavation, to support the 58 ft single-span, modular decked, beam superstructure. Recently, bridge elements have been accelerated. NDOR does not perceive a need for ABC, so it is not widely accepted, and its applications have been limited. However, contractors have used discretionary methods to accelerate construction, such as more man-hours. Standardizing elements is seen as a way to both lower costs and increase the quality and durability of finished bridge projects. Nebraska is currently studying the use of precast deck panels and heavy lifting of remotely assembled superstructure modules.
Nevada: The Nevada DOT (NDOT) has experience in using SPMTs, the bridge-slide technique, and precast arches. ABC is widely accepted when it is used for the right application, but the decision is left up to the contractor. Several NDOT projects have used GRS-IBS abutments and fully prefabricated superstructures.
New Hampshire: Although successful ABC projects are noted, the New Hampshire DOT (NHDOT) staff said not enough people at the agency were interested in ABC as a project delivery tool. They had no questions about its effectiveness, just insufficient motivation to evaluate. The University of New Hampshire continues to conduct research in the area. ABC is generally accepted, but when given the option, contractors seem reluctant to use it. When considered feasible and appropriate, projects are engineered to use ABC techniques, rather than leaving the decision to the contractor.
New Jersey: The New Jersey DOT (NJDOT) provided an extensive interview focused mainly on impediments. ABC has not taken hold because NJDOT engineers, particularly project managers, do not think it is a solution in many situations, based on their past experience and that of other NJDOT units. The agency is generally risk- averse, and ABC raises the level of risk associated with a project. If risk is not shown to be manageable, the concept will not gain traction, and it has not. NJDOT recognizes the need to study and update the user-cost model and its application, but it has no mechanism to screen or to choose projects for ABC and no systematic approach.
New Mexico: The New Mexico DOT (NMDOT) has completed approximately 10 projects in recent years. ABC is moderately accepted, and standardizing elements would help. Two projects used a fulldepth precast deck panel system, and one used precast pier caps, abutment caps, and wingwalls.
New York: The New York State DOT (NYSDOT) completed at least 10 projects using ABC methods, and although ABC is the exception rather than the rule, more and more ABC techniques are gaining acceptance, especially in the region around New York City. Projects are generally designed to use ABC, but contractors also submit substitution proposals opting to use ABC methods. Standardization would be less effective because the most beneficial applications tend to be less standard, such as projects in urban areas. Several pilot projects used UHPC for joints between precast components, deck bulb-tee beams for one bridge, and full-depth precast deck panels for another. NYSDOT is investigating fatigue in precast element joints. On June 17, 2015, it successfully placed a 1,100-ton assembly of three curved steel girders between two concrete piers near the Tappan Zee Bridge's Rockland County side, which took about four hours to complete.
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North Carolina: The North Carolina DOT (NCDOT) has recently completed several ABC projects, including 24-hours-a-day construction to replace seven bridges on Ocracoke Island in 90 days. The Washington Bypass project employs an innovative construction gantry that allows complete construction of a new viaduct from the top without any intrusion into environmentally sensitive areas. NCDOT has selection criteria for ABC projects and has discussed a role for the Alternative Project Delivery Unit, which typically enables innovation in several ways: as a proposal from the contractor in design-build contracts, an as-designed solution for special projects, and a VE proposal. NCDOT is currently exploring the use of mechanically stabilized earth (MSE) abutments and GRS-IBS to expedite foundation construction.
North Dakota: The North Dakota DOT (NDDOT) has completed no ABC projects, and the level of acceptance is low. Nonetheless, the decision to use ABC is left up to the contractor.
Ohio: The Ohio DOT (ODOT) has created "permitted lane-closure maps" that define which highway lanes can be closed for construction. ABC is used to reduce closure time in more urban corridors; projects are designed to fit set time frames in accordance with the maps, and contractors are forced to use ABC practices, though they are free to decide which practices they use. Standardization is not necessary because contractors specialize in certain construction practices. ODOT has experience with precast elements as well as SPMT roll-ins. In a first for the state, it used slide-in bridge construction to replace the I-75 bridges over U.S. 6 in Bowling Green in 2015. Traffic was disrupted for just a weekend instead of the months replacing a bridge typically takes.
Oklahoma: None reported.
Oregon: The Oregon DOT (ODOT) has completed 8 projects in the past 5-10 years using ABC techniques. Support for ABC is high, and practice is shifting from contractor-employed ABC techniques to DOT-designed ABC projects.
Pennsylvania: The Pennsylvania DOT (PennDOT) has used precast elements and SPMTs several times over the past 5 years. ABC is considered in every project, but the decision is left up to the contractor unless ABC promises a clear advantage, in which case PennDOT will engineer the project to use it. Past efforts at standardization have not translated into profits for contractors. Once ABC methods become more mainstream, costs and risks are predicted to decrease to the point where their use will be economical. PennDOT is not currently implementing ABC methods on any project but is involved in research on structural details that could be applied to ABC in the future.
Rhode Island: The Rhode Island DOT (RIDOT) replaced I-95 over Route 2 in halves using SPMT and prefabricated approach slabs in August 2014. The work took half the time of conventional construction and, prior to installation, had no impact on interstate traffic.
South Carolina: None reported.
South Dakota: The South Dakota DOT (SDDOT) most recently completed an ABC project in 2001 using SPMT to move a steel-truss superstructure to its abutments. The bridge spanned a railroad yard, so
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closures and outages had to be kept to a minimum. ABC is viewed favorably if project conditions warrant it. Interest in using ABC methods to construct jointless decks of adequate length for little or no increased cost is high.
Tennessee: The Tennessee DOT (TDOT) has completed one project in recent years that incorporates ABC methods. ABC is always considered for bridge projects but not often used. Standardized elements are considered to be useful along with proven installation and serviceability records.
Texas: The ratio of incentives to disincentives impedes further use. For example, low-bid contractors might not be able to perform ABC, but a suggested solution was to select the contractor who offers the best value, not the lowest bid. Project size is also an important consideration. Since most candidate bridges are either small or medium-sized, contractors will not have time to become efficient in the new methods on an individual project. In addition, precast components used for bridge substructures are only practical when several are needed or the available access makes CIP difficult. Contractors would like to choose whether or not to use ABC, so the Florida approach, laying out the requirements and specifications that have to be met, might be effective.
Utah: In 2010, The Utah DOT (UDOT) standardized ABC. Senior management unanimously supports it, and project selection criteria frequently lead to its use, rather than traditional methods. Presently, UDOT is delivering its ABC program through a combination of design-build contracts and a method known as Construction Manager/General Contractor (CM/GC), both of which have proven successful. At the same time, it is developing ABC standards for such modules as deck panels, precast substructures, and new prestressed beam sections. These standards will increase the flexibility to let contracts using various mechanisms and to communicate ABC intentions to the design and construction community. Once ABC standards become available for engineers to use in creating as-designed plans, UDOT will explore their use in more conventional design-bid-build contracts. Precast elements offer another opportunity for cost savings in substructure construction. During the early phases of implementation, contractors showed reluctance. UDOT held a series of workshops and scan tours to learn from other agency practices, and some contractors made changes to their business practices to compete in the ABC arena. Successful contractors have demonstrated a willingness to get into the precasting business. Projects let to date have demonstrated a 5:1 6:1 ratio of user-costs saved to construction-costs incurred, and with repetition, costs have decreased. Recent bridge project lettings indicate that full-depth precast decks are competitive with, and occasionally less expensive than, traditional CIP concrete decks and include time and quality savings.
Vermont: The Vermont DOT (VDOT) acceptance of ABC is generally good, and at least 5 projects using ABC methods have been completed in recent years. Projects are typically engineered to use ABC, but Vermont is considering the Florida approach, which allows the contractor to decide how to meet VDOT design specifications. VDOT is also investigating incentive/disincentive clauses to encourage contractors to use ABC.
Virginia: None reported.
Washington: The Washington DOT (WashDOT) has completed various ABC projects using traditional design-bid-build procurement and redesigning structures to accommodate ABC approaches. Projects
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included complete bridge prefabrication and large-scale prefabrication of superstructure and substructure elements. In general, the use of prefabrication and ABC techniques did not seem to affect project quality but had a beneficial impact on safety. WashDOT does not specifically require that user impacts be considered components of project cost but has used incentive/disincentive clauses to motivate project completion.
West Virginia: The West Virginia DOT (WVDOT) has completed at least 5 projects in the past several years that were designed to use ABC. Incentive/disincentive clauses were designed to motivate contractors to develop ABC approaches. WVDOT would benefit from ABC specifications and is interested in methods that minimize environmental disruption.
Wisconsin: The Wisconsin DOT (WisDOT) is just beginning to implement ABC practices. Its first project re-decked a major structure with a full-depth precast deck panel system. The level of support for ABC is not very high since the practice is new there and not well established. WisDOT is funding research on precast substructure units and looking for opportunities for a demonstration project (Wisconsin Highway Research Program - 0092-15-02 - Evaluation of Performance of Innovative Bridges in Wisconsin - Iowa State University, PI).
Wyoming: The Wyoming DOT (WYDOT) has completed several projects involving precast elements and decked bulb-tees for country road bridges. ABC is generally well accepted and used where appropriate. Seeing the design standards used by other states would lead to more use in Wyoming.
2.1.2 Impediments The impediments to ABC are widely noted. Many states cited increased cost as a major factor discouraging its use.
Alabama: Alabama cited increased manpower and other costs.
Alaska: ADOT&PF reported that the high initial cost of using a new technology is a major impediment. Contractor inexperience and the overall conservatism of the state are also hindrances.
Arizona: Currently, ADOT is facing questions about connection durability. Funding for ABC is limited, and contractors are inexperienced.
Arkansas: The primary concern is high initial costs. Incentives to use ABC are limited, and no active program is using ABC.
California: Caltrans is concerned about how precast pier elements will stand up to earthquakes; longterm durability; and elevated initial cost. The cost of ABC is widely known to exceed that of CIP, and although its time savings is also greater, Caltrans considers time secondary to financial savings.
Colorado: The high cost of ABC is the primary impediment, although it has become standard practice.
Connecticut: None reported.
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Delaware: DelDOT noted higher initial costs and longer hours for construction workers, which posed a problem for the contractors who have to pay them.
Florida: Though ABC is highly accepted in Florida, many impediments were noted; for example, lack of staging space for SPMTs in urban areas and inexperienced contractors. During the design phase, site traffic constraints must be accounted for since traffic maintenance and phased construction have posed problems. FDOT tries to balance out the higher ABC costs with user costs.
Georgia: GDOT is experiencing some of the same problems as other states, especially higher cost, but interest in using ABC, especially prefabricated bridge elements and PBES, is growing.
Hawaii: The only impediment is encouraging governing agencies to use ABC, although not for all bridge construction projects. These agencies fail to consider such factors as the use of temporary detours when bridges are being replaced or repaired.
Idaho: None reported.
Illinois: The main hindrances are higher cost expectations and that user costs are difficult to quantify.
Indiana: The lack of overall knowledge and proper pricing methods are impediments.
Iowa: Despite high acceptance generally, some contractors are reluctant to adopt ABC because they believe it is less profitable where traffic volumes are low. They believe ABC is too complex and are discouraged by low incentives. Higher level management supports the use of ABC wherever warranted, yet in some cases, production-level engineers find ABC design slow and frustrating. Standard plans and shapes might ease the design process and allow reuse to save money.
Kansas: The biggest obstacle is the cost difference between ABC and CIP methods. CIP bridges have fewer joints and are therefore cheaper and easier to maintain over time.
Kentucky: None reported.
Louisiana: None reported.
Maine: Cost is the biggest impediment; precast elements generally cost more than casting in place.
Maryland: None reported.
Massachusetts: Since MassDOT has not completed any ABC projects, general lack of familiarity with ABC is a major impediment. Contractors have a conservative CIP culture, but increased exposure through pilot projects should overcome it. More experience with ABC may also diminish concerns about financial risk.
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Michigan: The main hindrances are cost, constructability, and quality/performance. Life-cycle cost analyses with accurate accounting of public benefit would be useful for addressing higher costs, and constructability and quality concerns can be addressed by more experience in completing ABC projects.
Minnesota: Contractors are concerned about higher cost and that the reduced timeframes will mean tired, overworked staff. It is difficult to decide to use ABC methods late in the design phase.
Mississippi: MDOT is reluctant to use precast columns or footings based on concerns about connection durability and would welcome development of durable connections for these precast elements. They also do not use integral abutments due to concern about approach-slab connection details.
Missouri: MoDOT is concerned about durability and seismic activity and is working with local university partners for assistance in advancing ABC.
Montana: Low traffic volume is the main impediment. Interest in GRS-IBS systems is growing, but the overall perception is that ABC is not needed now.
Nebraska: ABC is primarily hindered by higher costs. Contractors are hesitant to use precast elements because of the amount of work that would have to be subcontracted. Urban areas are associated with higher user-delay costs, but the user costs on lower traffic roads and rural routes do not warrant ABC.
Nevada: The main concern is connection durability in case of seismic activity and questions about the efficiency of ABC methods and elements.
New Hampshire: NHDOT indicated that opportunities where acceleration appears justified are few. It also reported that the Epping project, one of its successful ABC projects, was 2.2 times more expensive than a conventional bridge replacement, and until the cost premium can be cut by at least 25% or less, promoting ABC will be difficult. Contractors hesitate to use the new technology and want to keep their own employees working rather than subcontracting work to precasters.
New Jersey: When NJDOT tried to accelerate earlier projects, their own construction engineering department was reluctant to support the schedule. Schedules are frequently lengthened based on traditional practices. The traffic operations staff also impeded prior efforts, allowing only short closure windows, which prolongs projects. The NJDOT incentive-disincentive opportunity is tied to computation of roadway-user costs, which are typically very low and do not justify acceleration. Designers are reluctant to suggest innovative approaches because they think NJDOT will not accept them. They have no incentive to be creative, and the state does not procure contracts requiring innovative design and construction solutions.
New Mexico: NMDOT considers accelerated techniques for every bridge project, but problems were noted on NMDOT's first full-depth precast deck panel project, the 2013 Eagle Draw Bridge renovation on NM 13. According to the report, the precast deck panels cost approximately 2.5 times the CIP system based on the bidder's prices. The primary pay items for the precast deck panels were the prestressed, posttensioned concrete; the 8.5-inch precast deck panels; and the epoxy urethane overlay used to create a
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smooth driving surface and to seal the joints between panels. If the job was done using CIP methods, the primary pay items would have been the concrete in which the deck would have only been 8 inches and epoxy-coated rebar. As one of only two such projects constructed by NMDOT, fabricators, contractors, and designers had no prior experience with full-depth, precast deck panels. The shop drawings for the precast deck panels, twice the number required for CIP construction, went through 5 iterations and took 4 months to be approved. In terms of fabrication, the bridge deck had a crown down the center, which meant one panel could not be used across the entire width, and closure pours had to be used at the abutments, piers, and down the center, causing the exposed rebar from the deck panels to come in contact with the rebar from the closure pours. The rebar then had to be field bent to avoid the adjacent reinforcement and shear studs on the prestressed girders. In addition, the precast deck panels had to be moved transversely over the width of the bridge because the posttensioning ducts in adjacent panels did not line up. This uneven alignment was noticeable along the edges of the deck. The strength of the precast girders was questionable, and since the girders had to be set up before the deck panels, the entire project was slowed. As far as construction was concerned, the contractor could only shut down NM 13 for 60 calendar days, but it could not be shut down until all precast elements were fabricated and accepted by NMDOT. Fabrication took longer than expected, so the contractor decided to close NM 13 at his own When the bridge was closed for over 120 days, the contractor was assessed penalties.
New York: Since the state is so heavily developed, staging is a particular problem. Construction costs are also an impediment; specifically, the use of precast, prefabricated elements and offsite construction using roll-in methods. NYSDOT was also concerned about the durability of precast component connections and joints. Local contractors resist using extensive prefabrication because of the large project share subcontracted out to specialists.
North Carolina: None reported.
North Dakota: The primary concerns are high cost, connection details, and the low level of support for ABC in the state.
Ohio: ABC costs more inevitably but are balanced by user costs when ABC is used on bridges with high average daily traffic (ADT) and relatively high importance to public transportation.
Oklahoma: None reported.
Oregon: In addition to the elevated initial costs, connections for seismic activity presented a major problem. Connections in seismic zones must withstand a much higher transverse loading and dynamic, repetitive loading. Most common connections have not been tested under lab conditions simulating seismic forces. Once the testing is completed, peer-reviewed, and reported, ODOT will have more confidence that connections of precast columns, footings, and pier caps can safely withstand the high horizontal and vertical uplift common in seismic events.
Pennsylvania: Contractors are generally unwilling to assume the additional associated risks with ABC. Because they are inexperienced, they have to subcontract work, which leads to inflated bids.
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Rhode Island: None reported.
South Carolina: None reported.
South Dakota: SDDOT is another state with low traffic volumes, so user costs do not balance the cost of ABC.
Tennessee: Questions about the durability and quality of precast members and connections, specifically attaching precast bridge decks to beams, impede ABC use.
Texas: The funding structure in the Texas DOT (TxDOT) provides no owner incentive to use rapid renewal methods other than staged construction. TxDOT districts may use only 5 percent of the project's cost and no more than 25 percent of road-user delay costs for incentives. Although road-user costs are considered, the owner has no way of collecting any savings from them. Therefore, if additional funds are spent to reduce road-user costs, fewer funds will be available for other projects. Federal grants to owners, based on the value of savings, would help them to capture savings from user costs and promote rapid construction projects. Moreover, the incentive amount must be sufficient to pay for the additional construction crews and/or special construction equipment needed for ABC and still result in profit. As an alternative, consider milestones with no-excuse bonuses. If the contractor can complete construction without excuses, then he or she is awarded a bonus but will be most likely to submit the bid assuming no bonus will be awarded.
Utah: At the outset of the ABC program, internal middle management was the biggest obstacle, particularly its conservatism, as in New Jersey. Convincing consultants, designers, and the contracting industry of ABC's merits was easier than convincing DOT staff. However, across the business, the core groups willing to try new things prompted a decision, and UDOT moved aggressively to implement trial projects. It still has some unanswered questions and sees areas for improvement; for example, in specifications, connection details and durability, seismic detailing, design considerations for moving structures, and acceptable deformation limits during movement. Nevertheless, UDOT is moving forward with ABC as a standard delivery mechanism.
Vermont: Vermont does not experience high traffic volumes, so road-user costs are often too small to create meaningful incentive/disincentive clauses in contracts that would encourage ABC projects. A way to incorporate savings from ABC methods, such as eliminating the need for temporary bridges, into incentive/disincentive clauses might change the picture.
Virginia: None reported.
Washington: None reported.
West Virginia: West Virginia contractors are inexperienced in ABC, and the state does not have a precasting industry or heavy-lift contractors. Contractors would probably use ABC standards, so ABC specifications and sample contracts would prove useful.
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Wisconsin: Contractors using ABC techniques in a project are most concerned about making money. Training would be beneficial.
Wyoming: With lower traffic counts, the main impediment to ABC implementation is justifying the higher costs.
2.2 INDUSTRIAL SURVEYS
The research team contacted various contractors around the country who had experience with ABC. It wanted to know what types of problems they encountered during the construction or design process and how they were resolved.
Hugh Boyle Engineering: Hugh Boyle Engineering (HBE) reported that the biggest problem on design-bid-build projects was modifying the original designer's details to fit an alternate ABC option or making the original ABC design easier to construct. According to this engineer, whether the owner and/or original engineer will accept HBE-proposed revisions is normally unknown, so HBE prefers design-build projects.
In HBE's experience, ABC designs try to emulate a traditional design as opposed to looking for alternative methods. For example, a bridge would be designed to use a lateral slide, yet its abutments would be designed to be fully integral because the owner wants to use a fully integral bridge. The solution would be to design a semi-integral system.
Precast element connections are also a concern. One of the most common problems is tolerances that are either too tight or unrelated to any functional requirements. Bridge flexibility is not recognized. Flexibility affects how loads are transmitted to equipment or supports used to move the bridge, which is especially serious for SPMT moves where the hydraulic system must balance structural loads.
HBE has also noticed a disconnection between acceptable tolerances and methods used to slide bridges. A specification may allow an elevation difference of up to 1/8" over 10' of a slide slab. A system can be designed to accommodate a significantly greater difference, but some systems need less tolerance. For example, on most of its slides, HBE uses only two supports per abutment because they are determinant. If one support goes up a little, its load barely changes due to a slight twisting of the structure between abutments; these systems can accommodate much more than 1/8" per 10'. However, when designers use a series of very stiff rollers under relatively stiff superstructures that require much less than the 1/8" tolerance, they still use the original 1/8" specs. With more than 2 supports, the system becomes indeterminate, and roller reactions are very sensitive to roller elevation. On these systems, a 1/8" variance over 10 feet might cause the entire bridge to rock over the high point, essentially putting all the load on a single point, which can be dangerous when the designer assumes that the loads will be evenly distributed over 5 supports. HBE is not actively working on any ABC projects; they have a lateral slide under contract, but the owners are considering cancelling due to budget constraints.
Kraemer North America: Kraemer North America, a privately held general contractor from Wisconsin, has had plenty of experience using ABC in various transportation and rail projects that included such methods as incremental launching, superstructure roll-in, transverse slides, and superstructure float-ins. The most
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common prefabricated bridge components they used were precast bent caps, columns, abutments, and full-depth panels. Further details on their experience in specific ABC projects are being sought.
Mammoet: Mammoet does not design or build bridges; they specialize in moving them with SPMTs. They are called in when an ABC project may need to use the skid or transverse-sliding method. A project manager explained, "We install our transporters underneath the prefabricated bridge and lift the drive, drive away with it, and install it in its final location. We design the support structure on top of our trailers but not the actual bridge. The engineer that designs the bridge already takes into account the fact that the bridge will be driven away. He also checks whether the supports that are under the bridge, will not damage the bridge, etc."
McFarland Johnson: McFarland Johnson (MJ) is another contractor with ABC experience. One project was the I-93 Exit 14 bridge in Bow-Concord, NH. MJ was involved in the initial phase and studied alternatives for improving the safety, mobility, and capacity of the I-93 bridge. After evaluation, it determined that ABC would be the best option for replacing the bridge. Each half of the superstructure was replaced within a 60-hour period. MJ used full-depth, precast concrete deck panels with high-early concrete and longitudinal posttensioning for long-term durability. MJ believes that ABC's advantages will provide future benefits.
2.3 SUMMARY Survey results for owners and contractors show the following impediments to ABC:
Higher costs; Inexperience with the techniques; Constructability concerns about connection details, congestion of rebar around joints, and staging
area; Resistance to innovation; and Design-bid-build contracts.
We learned that contractors prefer CIP construction for bridge renewals because the large prefabricated elements diminish their profits (Sivakumar 2014). Moreover, ABC involves a new technology, and contractors prefer to keep their own employees working instead of subcontracting work to precasters. Possible solutions to these and other impediments to ABC adoption are:
Introduce the industry to precast technology and demonstrate its profitability; Use pre-engineered modular systems that can be built with conventional construction equipment,
enabling local contractors to bid on rapid replacement projects; Bundle several bridge projects with similar requirements into a single construction contract,
allowing a local contractor to get more benefits from repetition; and Use full-moment connections with UHPC, which will satisfy the criteria for constructability,
structural requirements, and durability in prefabricated modular superstructure systems.
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CHAPTER 3. ABC DECISION-MAKING TOOLS
The ABC decision-making tools is a section devoted to provide guidance on when to use ABC versus conventional bridge construction. If ABC is found to be the most efficient type of construction, then this section will also serve as a guide as to which ABC method is deemed most appropriate for a specific project.
Appendix F presents a Decision Making Matrix, an ABC Decision Flowchart, and a Decision Making Scoring Chart and descriptions of items that can be used in conjunction with one another to answer whether to use ABC or conventional methods.
The Decision-Making Matrix in Appendix F may be used to determine how applicable ABC is for a specific project. This matrix is utilized by tallying up the total amount of points next to each section and finding the overall score for a project. Each of the sections listed in the Decision Making Matrix is explained in further detail within the Decision Making Scoring Guidance which is also located in Appendix F. After a total score is determined from the Decision Making Matrix, that score is then used to enter the Decision Making Flowchart at the appropriate location. The Decision Making Flowchart is designed to help the user make an intelligible decision on whether ABC or a conventional method is the best decision for the project. Once the correct scoring location is determined the question "Do the overall advantages of ABC negate any additional costs?" is to be answered. These additional costs may include schedule, traffic impacts, funding, road user costs (RUC), etc. This question is to be answered on projectspecific basis taking into consideration all engineering components and professional judgement, and also the available project information. This question is a part of the Decision Making Flowchart in order to assist the user of the Decision Making Tools in analyzing and making an intelligent decision on whether ABC is in fact the best form of construction for a project. After answering this question and concluding that ABC is in fact the best method, the part of the Decision Making Flowchart afterwards will help guide the user to the best form of ABC for the project.
These Decision Making Tools can help to provide insight into which method would be deemed most efficient, however they are not considered to give an exact answer. After reviewing the outcome from the Decision Making Tools it is up to the user to decide whether ABC does in fact make the most sense for the specific project at hand. There is no definitive answer provided upon the completion of the Decision Making aspect of ABC versus Conventional, it is up to the user's better judgement.
The Decision Making Flowchart can incorporate a variety of resources that are pertinent which may include (but are not limited to) "Program Initiatives", like research needs, local resources, input from the public, requests of stakeholders, or structure exhibits. These items should be considered on a projectspecifics basis.
While the Decision Making Flowchart is designed to lead the user to the best method for ABC, it should be noted that there is room to combine methods listed at the bottom of the flowchart (i.e. PBES, GRS-IBS).
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CHAPTER 4. ABC DESIGN CONCEPTS
This chapter presents current developments in ABC design that can be used for future projects in Georgia. It should be noted that ABC projects use innovative designs that are also compatible with innovative construction techniques because they are highly interrelated. ABC design strategies have the following goals (SHRP2 2014):
As light as possible This concept improves the load rating of existing foundations and piers, and can simplify the transportation and erection of bridge components.
As simple as possible To achieve this goal, it is recommended to reduce the number of certain elements, such as girders, field splices, and bracing systems.
As simple to erect as possible Fewer workers and fresh-concrete operations on site are desirable. Additionally, geometry needs to be simple.
The following sections discuss design considerations and concepts for prefabricated systems in detail.
4.1 MODULAR SUPERSTRUCTURE SYSTEMS Pre-engineered standards include the concrete and steel girders under modular superstructure systems. When researchers evaluated new construction techniques, technologies, and bridge systems, including lab testing, deck bulb tees and decked steel stringer systems received the highest scores, reflecting what has been used in the field for rapid renewal. Due to the quality of the prefabricated superstructure, highperformance concrete, and attention to different connections, the modular system is predicted to have a 75- to 100-year service life. Modular superstructure standards for steel and concrete will include:
Decked steel stringer system; Composite steel tube girder system; Concrete deck bulb tees; and Deck double tees.
4.1.1 Decked Steel Stringer System Like concrete deck girder systems, the decked steel stringer system has proven quite economical and quick to construct (See Fig. 4.1). The use of a modular decked steel system for ABC has become quite popular with states that employ rapid construction techniques.
When compared to precast concrete units, the modular steel system is much lighter, easier to construct, less expensive and easier to fabricate. Each aspect of the system, including the length and weight of the module, can be tailored to suit the particular mode of transportation and erection methods for each case. Conventional construction equipment can usually be employed to erect these steel units, and UHPC is used for closure pours to connect each unit.
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(a)

(b)

(c)

Figure 4.1. Decked Steel Stringer System. (a) Steel grid open or filled with concrete (photo: D.S. Brown Co.). (b) Full-depth precast deck panels with and without longitudinal post-tensioning

(FHWA, 2015). (c) Partial-depth precast deck panels (photo: Keegan Precast on project in

UK by contractor Laing O'Roruke).

Standard designs of common span lengths will assist in gaining acceptance and more widespread use for modular concepts. Full moment connections are preferred in steel girder systems for the same reason they are in concrete girder systems. In many cases, an integral wearing surface, with a thickness between 1.5 in. and 2 in., can be built with the deck to assist in future surface replacements without damaging the structural deck slab.

4.1.2 Composite Steel Tub Girder System Composite steel tub girder superstructures can be built in the shop in large scale, transported to the site, and then erected by assembling the pieces together with a minimal need of formwork. (See Figs. 4.2 and 4.3). If there is enough room adjacent to the project site, decks can be cast on site. In addition, these systems can be fabricated as longitudinal sections that can be erected piece wise and assembled together using in-place posttensioning, or they can be fabricated as full-width deck systems that can be erected in a single piece.
Trapezoidal steel box girders are very suitable for this type of large construction. They offer light, cost-effective solutions while providing structural efficiency during transportation, erection, and service life. Trapezoidal box girders building blocks can be designed with a single box, two boxes, or as many as needed to complete the width of deck. Twin tub girders, however, are the most popular standard. These bridges can be designed and constructed to function as simple spans or continuous structures. Several connection details are available and can be used to provide continuity for dead and live loads, either as standard splice construction procedures or specific details applicable to the particular situation on the site.

(a)

(b)

(c)

Figure 4.2. (a) Steel tub girder (photo: Greg Price, DHS Discussion Forum). (b) Concrete tub girder (photo:

StressCon Industries, Inc., website). (c) Open trapezoidal composite box girder (photo:

SteelConstruction.info).

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Figure 4.3. Composite Steel Tub Girder (SHRP, 2014).
4.1.3 Precast Concrete Deck Bulb Tee and Double Tee Conventional precast concrete girders have been perfected and used all over the United States for more than 50 years. Owners and contractors use these types of bridges because they are easy and economical to build and maintain. In most cases, the girders are used with a CIP deck built on site. For ABC, the major difference is that the girders will now have integral decks, eliminating the need for CIP (See Fig. 4.4). This concept of precast decked girders has increased in popularity in several states, but is not used all over the country. The integral wearing surface, which is typically 1.5 in. to 2 in. thick, can be built monolithically or in addition to the deck slab. In the future, the wearing surface concrete can be removed and replaced while preserving the structural deck slab. The precast deck bulb tee girders and double tee girders combine the benefits of eliminating the time it takes to make CIP decked superstructure along with the positive attributes of precast girder construction. This ABC approach should be easily adopted by experienced contractors if they have prior knowledge of conventional precast girder construction.

(a)

(b)

(c)

Figure 4.4. (a) Adjacent deck bulb tee beams (FHWA, 2015). (b) Adjacent double tee beams (FHWA, 2015). (c) NEXT beam (drawing on High Steel Structures LLC website).

Utah, Washington, and Idaho have proven and standardized deck bulb tee and double tee girders. The Precast/Prestressed Concrete Institute (PCI) Northeast developed the northeast extreme tee (NEXT) beam, a variation of the double tee, to serve the ABC market. This deck girder is expected to be competitive with girder and CIP deck systems. It may also be beneficial for sites where deck-casting operations are constrained. CIP closure pours are typically used to connect girders in the field. These girder flanges can be made to different widths to fit site and transportation requirements.

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4.1.4 Pre-Topped Trapezoidal Concrete Tub Beams Pre-topped trapezoidal concrete tub superstructures have been developed using TxDOT U beams for spans up to 115 ft, which can be transported and erected in one piece. Standards for this system, usually, would be developed to cover span ranging from 60 to 175 ft, with no more than five standard cross sections (See Fig. 4.5). There are two options to construct pre-topped U beams: 1) Spans 60 to 115 ft, transported and erected in one piece; and 2) Spans 60 to 175 ft, transported in 10 ft long, and posttensioned on site. The following design concepts can be considered for pre-topped U beams:
The use of available standard U sections can minimize fabrication costs. Design can be improved to use high-performance materials to reduce weight. Lengths less than 115 ft produce sections under 150 tons for shipment in one piece. Units would be designed to handle transportation and erection stresses. An overlay can be provided with this system and still allow the bridge to be opened within 4
days of the beginning of superstructure erection. Limit the number of standardized sections to 5. Provide two or three suggested methods of erection, such as cranes, launching, and overhead
gantries. Edge sections of deck with curb pieces to allow bolting of prefabricated barriers.
Figure 4.5. Cross Sections of Pre-topped, Trapezoidal, Concrete U Beams (SHRP2, 2014).
4.1.5 Full-Depth Precast Concrete Deck Systems Full-depth precast concrete deck systems allow the bridge to be reopened to traffic faster, as CIP concrete is needed only at the joints between the prefabricated panels (see Fig. 4.6). The CIP joints can also be replaced by match cast joints, which can save time and efforts. The match cast joints method uses each segment matching cast against its adjacent segment to form a precision fit. The joint width between the installed segments is very small, and any gaps are taken up with epoxy paste. Eliminating the CIP joints with match cast joints accelerates the schedule considerably. The addition of post-tensioning does not increase the time of construction because the posttensioning is required to extrude the epoxy on match cast joints and occurs simultaneously. NCHRP Report 584 (Badie and Tadros 2008) addresses the optimum benefits and opportunities of full-depth precast concrete deck panels.
A fully composite connection between the concrete deck panels and the steel or prestressed concrete girders are the primary concern for a precast deck panel system. There have been several research for the use of higher-capacity shear studs and innovative construction. Full-depth concrete deck panels offer a number of innovative opportunities as listed below:
Durable transverse panel connection for staged construction. One possibility for this application is the use of UHPC, which has been successfully used by NYSDOT.
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Reduced dead load to simplify installation. The use of lightweight concrete, ultra-highperformance materials, or a waffle-slab configuration offers significant potential.
Improved riding surface. Improvements in shimming and match casting to provide a smooth surface immediately after placement would be beneficial.
Figure 4.6. Full-depth Precast Concrete Deck System (SHRP2, 2014).
4.1.6 Ultra-High Performance Concrete (UHPC) Superstructures The extremely high strength and durability of UHPC make it a valid candidate for consideration in standardized ABC components. UHPC is composed of fine sand, cement, and silica fume in a dense, low water-to-cement ratio (0.15). Compressive strengths of 18,000 to 30,000 psi can be achieved, depending on the mixing and curing process. UHPC has an average strength gain of 10 ksi in 48 hours, which is when deck grinding can begin. The material has an extremely non-existing intrusion of chloride-laden water. To improve ductility, steel or polyvinyl alcohol (PVA) fibers (approximately 2% by volume) are added, which replace the use of mild reinforcing steel. Although, however, the UHPC material was designed to function without conventional reinforcing, it might be an option to provide nominal reinforcing as a redundant system.
Full moment connections coupled with UHPC joints are the preferred connection type for ABC purposes regardless of which modular system is used, because of their structural behavior and durability. Prefabricated components with UHPC connections have proven to have increased connection performance over time when compared to conventional construction materials and practices. The properties of UHPC allow for the use of small-width, full-depth closure pour connections between modular components that can withstand the abuse of vehicular impacts and heavy loading. Connection size of UHPC joints compared to conventional concrete are much smaller because of their impressive strength.
The narrow joint width reduces concrete shrinkage and the quantity of UHPC required, while providing a full moment transfer connection. UHPC, however, is not cheap or easy to work with so the less that is required the better. For example, this material is projected to cost three to five times as much as conventional concrete. A longer cycle of casting and heat curing is also required to achieve extremely high compressive strength. Furthermore, the limited number of casting locations in the United States might be a potential impediment.
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4.1.7 Connections between Modules The ease and speed of construction of a prefabricated bridge system in the field have direct correlation to its acceptance as a viable system for rapid renewal. ABC construction time is greatly influenced by the speed with which the connections between modules can be assembled. Connections between modular segments can also affect live load distribution characteristics, seismic performance of the superstructure system, and the superstructure redundancy. Connections play a crucial role when designing with this approach. Often, the time to develop a structural connection is a function of cure times for the closure pour. Joint detail and number are crucial to the speed of construction, to the overall durability and the amount of long-term maintenance the final structure will require. The use of CIP concrete closure joints should be kept to a minimum for accelerated construction methods due to placement, finishing, and curing time.
To enhance load transfer, prevent cracks under live loads and close shrinkage, the use of induced compression in post-tensioned joints is favored. The post-tensioned joints can present a female-female shear key arrangement infilled with grout or match-cast with epoxied joints, but only if precise tolerances can be maintained throughout the lifetime of the bridge. This process will provide long-term performance. Post-tensioning requires an additional step and complexity during on-site construction, therefore, its use may slow down field assembly and compromise long-term durability which makes it unfavorable for ABC.
Design considerations for connections between deck segments include:
Full moment connections that can be built quickly. At least as durable as the precast deck. Joints that can suit heavy, moderate, and light truck-traffic sites. Ride quality that is at least equal to CIP decks. Durability even without overlays on the deck. An integral wearing surface consisting of an extra
thickness of concrete over the structural slab can help. Post-tensioned connections can be an alternative for ABC construction. Details that can accommodate slight differential camber between neighboring modules. Quick strength gain, so that traffic can be opened with very little delay.
4.1.8 Summary of Design Considerations for Modular Superstructures
Design considerations for modular superstructure systems include:
Pre-engineered standards for modular construction. Designs that can be used for most sites with minimal bridge-specific adjustments.
Optimize designs for ABC and use of high-performance materials. Simplicity and efficiency of design, availability of sections, and short lead times are key considerations.
Usually length 140 ft, weight 100 tons, width 8 ft for transportation and erection using conventional construction equipment.
Able to accommodate moderate skews. For rapid renewal, it would be more beneficial to eliminate skews between bents and the longitudinal axis of the bridge.
Segments designed for transportation and erection stresses, including lifting inserts. Sweep of longer beams should not be an issue for erection as there is an opening between the beams.
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Segments that can be installed without the need for cross frames or diaphragms between adjacent segments. This improves speed of construction and reduces costs. Use of diaphragms is optional based on owner preference.
Segments that can be used in simple spans and in continuous spans (simple for dead load and continuous for live load). Details to eliminate deck joints at piers. Details for live load continuity at piers to be included for use as required.
Use of high-performance materials: High Performance Concrete (HPC)/UHPC, High Performance Steel (HPS), or A588 weathering steel. Consider lightweight concrete for longer spans to reduce weights of deck segments.
Deck tees and double tees with minimum 8-in. flange to function as decks with integral wearing surface so that an overlay is not required. Use of overlay is optional.
Cambering of steel sections for longer spans. Control fabrication of concrete sections, time to erection, and curing procedures so that camber differences between adjacent deck sections are minimized. Leveling procedure to be specified to equalize cambers in the field during erection.
Deck segments when connected in the field should provide acceptable ride quality without the need for an overlay. Deck segments to have -in. concrete overfill that can be diamond ground in the field to obtain a desired surface profile.
Limit the number of standardized designs for each deck type to five, which should cover span ranges from 40 ft to 140 ft. Consider steel rolling cycles and sections widely available.
Segments designed to be used with either full moment connection between flanges or with shearonly connections. Each flange edge needs to be designed as a cantilever deck overhang.
Design for sections that can be transported and erected in one piece. Lengths up to 140 ft may be feasible in certain cases. Provide one method of erection. (Spans longer than 140 ft may be erected by shipping the segments in pieces, splicing on site, and using a temporary launching truss for erection.)
Design for sections that can be transported in pieces and spliced on site before erection to extend spans to 200 ft and beyond. Develop two alternate erection techniques when conventional lifting with cranes may not be feasible due to weight or site constraints.
Edge sections of deck with curb piece ready to allow bolting of precast barriers. Provide standard details for durable connections between deck segments.
4.2 MODULAR SUBSTRUCTURE SYSTEMS
A significant portion of the on-site construction time is dedicated to building the substructure. Reducing the time for substructure work is critical for all rapid renewal projects. Precasting as much of the substructure as possible will allow for faster construction of the bridge and reduce interference with normal system operation. With this in mind, this section provides details about modular systems for abutments, wingwalls, and piers that are commonly used in routine bridge replacements. These standards include the following:
Precast modular abutment systems. See Fig. 4.7(a). Precast complete pier systems. See Fig. 4.7(b) Hybrid drilled shaft/micropile foundation systems. See Fig. 4.7(c).
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(a)

(b)

(c)

Figure 4.7. (a) Precast modular abutment systems (SHRP2, 2014). (b) Precast complete pier system (FHWA, 2015). (c) Hybrid drilled shaft/micropile foundation (SHRP2, 2014).

4.2.1 Integral and Semi-Integral Abutments Installing roadway expansion joints and expansion bearings can slow down construction considerably, raise lifetime maintenance costs and reduce the life of the structure. Therefore, these expansions tend to be avoided. Besides providing a more maintenance-free durable structure, eliminating joints and expansion bearings can make the bridge design more innovative and may result in cost efficient solutions regarding construction. Providing a bridge design with minimal joints and maintenance liabilities should be an important goal while planning rapid renewal projects. The use of integral or semi-integral abutments allows the joints to be moved beyond the bridge and into the abutments. Integral bridges are bridges where the superstructure is continuous and connected monolithically with the substructure with a moment-resisting connection. Bridges utilizing integral abutments have proven to be cheaper to construct, easier to maintain, and more economical to own over their lifespan. These types of abutments, integral and semi-integral, are preferred in bridge construction by most DOTs.
The downside to eliminating deck joints is that alternative ways must be found to account for creep, shrinkage and temperature change. Usually, provisions are made for thermal movement at the ends of the bridge by using either integral or semi-integral abutments. Along with adding these abutments, there is a need to place a joint in the pavement or at the end of a concrete approach slab. Continuous jointless bridges are generally referred to as "integral bridges" and "integral abutment bridges (IAB)". Stub or propped-pile end caps are commonly used when designing a bridge due to their superior flexibility. The flexibility offered by these end caps provides little resistance to cyclic thermal movements. A single row of vertical piles is highly recommended to provide a high level of flexibility to combat thermal movements.
The semi-integral abutment bridge (SIAB) is related to the integral abutment design. In SIAB, only the backwall portion of the substructure is directly connected with the superstructure, due to this change there will be no expansion joints within the bridge. The stationary abutment stem holds the bearings which holds the beams so the superstructure and backwall will move together during thermal expansion and contraction.

4.2.2 Jointless Construction
ABC is intended to reduce on-site construction time and eliminate long traffic delays through the use of precast components and innovative construction practices. Eliminating joints results in faster construction and a surplus of money that can be allocated to other aspects of the construction process. Some of the advantages to jointless construction for ABC projects are summarized as follows:

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Issues with tolerances are reduced. The close tolerances required when using expansion bearings and joints are eliminated by using integral abutments. Minor mislocation of the abutments does not create problems with the final fit of the bridge.
Rapid construction. With integral abutments, only one row of vertical (not battered) piles is used and fewer piles are needed. The backwall and superstructure can be cast together with less forming. This reduces the amount of materials needed, and thus reduces the cost of the project. Fewer issues are encountered with scheduling between suppliers and manufacturers. Integral abutment bridges are faster to erect than bridges with expansion joints, which leads to cost savings. IABs are quicker to construct because the connections involved are simple to form, and there are no expansion joints to slow down construction.
Reduced removal of existing elements. Integral abutment bridges do not require the complete removal of existing substructures, and can actually be built around existing foundations. Reducing the amount of demolition entailed with the construction process will greatly reduce the overall duration of the project.
No cofferdams. Integral abutments are generally built with capped pile piers or drilled shaft piers that do not require cofferdams.
Improved ride quality. Jointless bridges provide a very smooth ride and diminish the impact stress a car experiences. This translates to lower impact loads and, for snow prone areas, less deck damage due to snowplows.
Integral abutments provide an added element of redundancy in components and capacity for many types of catastrophic events. When seismic events are considered in designs, a significant amount of material can be cut from the design by using integral abutments which do not need enlarged seat widths and restrainers. Integral abutments completely eliminate the loss of girder support, which has proven to be the most common cause of bridge damage in seismic events. The presence of joints creates a much higher potential collapse risk of the overall bridge structure. In the past, integral abutments have consistently outperformed standard CIP bridges during actual seismic events, and have shown very minimal problems with backwall and bearing damage that are associated with seat-type jointed abutments.
4.2.3 Precast Abutments and Wingwalls Bridge abutments are constructed in several different pieces off site in a factory, shipped to the construction site and then put together in the field (See Fig. 4.8). ABC construction companies have preferred an integral connection of the superstructure and substructure. The different components that are being shipped on site should be designed to be transported over roads and constructed using typical construction equipment. To this point, the precast components are made as light as practicable. Voids can be used in the wall sections of larger elements. This is to reduce their weight and facilitate their fabrication and shipment. Voids are also used to attach drilled shafts or piles to the cap for stub-type abutments. Once the components are constructed into place, the voids and shear keys are filled with selfconsolidating concrete. Wingwalls are also precast with a formed pocket to slide over wingwall piles or drilled shaft reinforcing. Once this process has been completed, the wingwall pockets are filled with high early strength concrete or self-consolidating concrete.
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(a)

(b)

(c)

Figure 4.8. (a) and (b) Precast modular abutment systems. (c) Precast wingwall (SHRP2, 2014).

4.2.4 Connections CIP construction can be eliminated by full-moment connections between modular substructure components. The closure pours are constructed using self-consolidating concrete which makes them easy to construct and results in a highly durable connection. Self-consolidating or self-compacting concrete (SCC) is used to enclose or encapsulate congested reinforcements. This is due to the fact that SCC is highly flowable and non-segregating. It fills formwork without the need to employ any mechanical vibration. SCC is also an ideal material to fill pile pockets in substructure components. This kind of concrete mix can be placed purely by means of its own weight, with little or no vibration. SCC allows easier pumping, flows into complex shapes, transitions through inaccessible spots, and minimizes voids around embedded items to produce a high degree of uniformity.

4.2.5 Precast Complete Piers Precast complete piers consist of separate components premade off site, shipped, and fabricated onsite (See Fig. 4.9). Piers with single-column and multiple-column configurations are common. Foundations can consist of drilled shafts, which can be extended to form the pier columns. When soil conditions are appropriate, precast spread footings can be employed. However, if soil conditions do not permit these footings, driven piles may be used with precast pile caps. Pier columns are attached to the foundation by grouted splice sleeve connectors. Precast columns can be square or octagonal, the tops of which are connected by grouted splice sleeves to the precast cap. The precast cap is typically rectangular in shape. The pier bents may have single or multiple columns.
States in high seismic regions use integral pier caps. However, the standards in this project were developed only for non-integral piers, which have been found to present more benefits in rapid construction. When using integral pier cap connections, CIP concrete is commonly used. However, the connection can also be made with precast concrete, but it often requires a complicated and lengthy procedure. There are also tight controls over tolerances and grades so the most common form of connection is a CIP concrete closure pour. In a non-integral pier cap, the superstructure and deck will be continuous and jointless over the piers which makes them easier to reuse.
As it is the case with precast modular abutments, the precast piers have been designed to be shipped from the fabrication location to the construction site. To this point, the precast components are made as light as practical for shipping purposes. Precast spread footings can consist of partial precast or complete precast components. To avoid localized point loads, a grout-filled void will be formed beneath the footing to transfer the load to the soil. Column heights and cap lengths will be limited by transportation regulations and erection equipment, but these cap length limitations can be avoided by forming multiple
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short caps that will function as a single pier cap would. Precast bearing seats can also be used for pier design.
Figure 4.9. Precast Concrete Pier (SHARP2, 2014).
4.2.6 Hybrid Drilled Shaft/Micropile Foundation Systems A hybrid system is composed of conventional drilled shaft and clusters of micropiles, whereby the upper portion (10 to 20 ft) of the deep foundation is constructed by conventional drilled shaft and the lower portion of the shaft is composed of micropiles. Above grade, the drilled shaft is extended to serve as a circular pier column, eliminating pile cap foundation construction. Below grade, the drilled shaft portion of the hybrid foundation need to extend only to the depth required by design, with due consideration of flexural demands and extreme events relating to scour and seismic design.
Micropile foundation systems have several advantages for ABC. One is the possibility to use lowcost, small-footing, all-terrain drilling rigs for installation, and to employ segmented 5 to 12 in. nominal diameter high-strength steel casings that allow for rapid installation in low head-room conditions. Another advantage associated to the use of micropiles is a reduced construction risk, since a failed micropile can simply be abandoned and replaced with a closely adjacent one.
4.2.7 Steel or Fiber-Reinforced Polymer (FRP) Jacket System for Existing Column Jacketing has been used to extend the life of bridge columns that may suffer from significant spalling due to corrosion of reinforcing steel, or for columns that must be upgraded for seismic considerations. External jacketing is used to provide the desired level of confinement without the need for expensive, time-consuming replacement. The concept of column jacketing can be used not only as a retrofit for providing additional capacity, but also as a means for accelerated construction without on-site formwork.
The use of steel or FRP jacket systems has achieved success for retrofitting and strengthening of existing concrete piers for many years (See Fig. 4.10). These jacket systems offer a number of advantages for accelerated construction:
Prefabricated shell components can be easily standardized in a variety of commonly used shapes and sizes.
Easy transportation and erection on site.
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No on-site formwork to be constructed and stripped. Suitable for use with all foundation types, including footings and drilled shafts.

(a)

(b)

(c)

Figure 4.10. (a) Steel/FRP jacket concept (SHRP2, 2014). (b) Steel jacketed bridge column (Nelson, 2012). (c) FRP jackets in several bridge columns (Buccola, 2011).

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CHAPTER 5. RISK ANALYSIS
The risk-assessment component of the toolkit enables the user to determine how to best convey surface water (if applicable) and storm water runoff in order to minimize damage to the roadway, bridge itself, and other property. This process starts by helping the user decide if a culvert or bridge is most appropriate for the site. If a culvert is selected, the toolkit assists in helping the user select the culvert's shape, material, and initial size. If a bridge crossing is most appropriate, the toolkit provides the user with information as how the hydrologic and hydraulic considerations influence the bridge foundation investigation (BFI) and scour analysis components of the bridge design.
5.1 THE ROLE OF RISK IN CULVERT AND BRIDGE DESIGN Since rainfall events are governed by chance, historical rainfall information and statistical analysis are used to estimate the magnitude of different storm events over different return periods (example: 50 year storm). Knowing this information about a storm, along with information about the physical attributes of the watershed (area, slope, soil type, vegetation cover, percentage of impervious surfaces) allows us to predict how much water will drain from the watershed and eventually drain through the culvert or under the bridge.
Risk is a measure of the probability of occurrence multiplied by the cost associated with repairs/replacement caused by the event. Since a storm's return period (20 year, 50 year, etc.) is inversely related to probability that the storm will occur that year, there is a direct relationship between the storm period and risk. While larger return periods have lower probabilities of occurrence, the tradeoff is that they also have higher construction costs. For example, using a return period at 20 years (probability of equaling or exceed the storm is 1/20 or 5%) might result in a project with a low initial construction project cost but with frequent repair or replacement costs. Conversely, using a large return period of 200 years (probability of equaling or exceed the storm is 1/200 or 0.5%) can result in an overly designed project with an excessive construction cost. Since the selection return period requires careful consideration of several factors (potential damage to highway and property as a result of flooding, potential hazards and inconveniences to the public, and project costs) GDOT specifies the required return periods (flood frequency) that should be used for both culverts and bridges (GDOT, 2014):
Culverts for state routes and interstate highways shall be designed using a 50 year flood frequency.
Bridges for state routes and interstates shall be sized so that a 50 year flood is conveyed only through the bridge opening and the 100 year flood is conveyed through the bridge opening and over the roadway.
5.2 CHOOSING BETWEEN A CULVERT AND A BRIDGE CROSSING Culverts are closed conduits that covey surface water or storm water runoff from one side of a road to the other side. They play a key role in preserving the road base by preventing water from overtopping the road surface and by keeping the sub-base dry by draining water from ditches along the road. Whereas bridges use the bridge deck, superstructure (beams, girders), and substructure (abutments, piers) to
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support vehicle loads, culverts rely on the structural properties of the conduits and the embankment material covering them and to support these loads.
In cases in which the toolkit user needs to decide between using a culvert or bridge crossing, the following guidelines should be applied:
Cases in which a bridge crossing is recommended: Area draining to the crossing exceeds 20 miles2 (12,800 acres). Cases in which the surface water canal is navigable. Cases in which the water area at the crossing is undefined. If the crossing point is located near an area where flow back up behind the culvert could flood residential areas (Ministry for the Environment, 2004). If high debris loads (gravel, trees, logs) passing below the roadway are likely. Cases in which the hill catchments is steep (rule of thumb value is 6% or larger) (Ministry for the Environment, 2004). When the required culvert size (with minimum soil cover) exceeds the elevation difference between road and canal or drain.
Conversely, culverts can be used when: Area draining to the crossing does not exceed 20 miles2 (12,800 acres). Surface water is limited or not present. The water area is well defined (i.e. easily be routed through the culvert). Cases in which large debris will not pass below the roadway. Cases in which any flow backup will not flood adjacent areas.
5.3 SELECTING A CULVERT TYPE AND SIZE A culvert's shape (Fig. 5.1 for common shapes) and material depends on site-specific characteristics including: the elevation difference between road and canal or drain (available soil height), required span, and bearing capacity of the soil. Other important factors include: material and installation cost, needs of fish and other aquatic organisms, and local preferences. Circular (pipe), box, and arched culverts similar to the ones shown in Fig. 5.2 are most commonly used.
Figure 5.1. Common Culvert Shapes (Purdue University, 2005).
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(a)
(b)
(c) Figure 5.2. Pipe (a), Box (b), and Arch (c) Culverts (Cranberry Township, American Concrete Industries, and
Contech, 2015). 33

Culverts are made using a wide variety of materials. While concrete, reinforced concrete, steel (smooth and corrugated), corrugated aluminum, and plastic (high density polyethylene) are the most common, vitrified clay, bituminous fiber, cast iron, wood and masonry culverts are occasionally used. By definition, culverts must have a clear span of no more than 20 feet (GDOT, 2014). If the culvert's clear span exceeds 20 feet, then it is designated as a bridge culvert (See Fig. 5.3). When multiple culverts are installed side by side, referred to as a multi-barrel culvert, then span can exceed 20 feet (and still be designated as a culvert) if the spacing between culverts is less than half the culvert width/diameter (GDOT, 2014). For instance, while the total span of the multi-barrel box culvert in Fig. 5.2(b) exceeds 20 feet, because the spacing between each culvert is less than half the culvert width, this is designated as a culvert and not a bridge culvert.
Figure 5.3. Bridge Culvert (Contech, 2015).
5.4 PROCESS FOR SIZING AND DESIGNING CULVERTS There are many hydrologic, hydraulic, economic, and site-specific factors that must be considered when designing a culvert. In addition to knowing how much water is required to be transported by the culvert (refer to previous section on risk), factors such as culvert slope, conduit material properties (roughness, strength), soil characteristics, and water velocity must all be considered as part of a hydraulic evaluation. Flow through culverts can be complex depending if either end of the conduit (barrel) is submerged (covered) by either (or both) the headwater or tailwater ends (See Fig. 5.4). As such, GDOT requires that all culvert designs follow the guidelines presented Chapter 8 of the 2014 GDOT Manual on Drainage Design for Highways. This includes a requirement for the designer to utilize either the HY-8 Culvert Hydraulic Analysis Program or the Hydrologic Engineering Centers River Analysis System (HEC-RAS) culvert modules.
In addition to the hydrologic and hydraulic considerations, culvert design is also dependent on the impact of fish and other aquatic organisms, any local preferences, construction and maintenance costs.
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Figure 5.4. Culvert Cross Section showing Headwater and Tailwater Levels (Purdue University, 2005).
5.5 PROCESS FOR SIZING CULVERTS AND REQUIRED BRIDGE OPENINGS While a detailed culvert design requires the expertise of an engineer familiar with the GDOT guidelines and the necessary software, the toolkit provides the user with the ability to determine an initial culvert size for estimating purposes. The following steps outline the process that is used within the toolkit. Step 1: Delineating the Watershed A watershed is an area that drains to a common point of discharge (outlet). Since water flows downhill through gravity, identifying the boundary (delineating) a watershed involves using a topographic map to identify the outlet or downstream point and then locating the boundary at which any rains falling within the boundary will be directed towards the outlet. Fig. 5.5 below shows an example of a delineated watershed boundary.
Outlet
Figure 5.5. Example of a Delineated Watershed Boundary (Natural Resources Conservation Service, 2014). The area of the watershed can be determined using various techniques. GDOT recommends using the United States Geological Survey (USGS) application StreamStats (http://water.usgs.gov/osw/streamstats/georgia.html) which allows the user to click on the culvert/bridge crossing point and have the software compute the watershed area. Area can also be manually estimated by using a planimeter or by counting the square grids and multiplying by the map scale. For example, for
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maps with a 1:24,000 scale (1 inch represents 2,000 feet) one square grid represents 4 million square feet or 91.8 acres). At a scale of 1:24,000, the map shown in Fig.5.5 would have an approximate area of 3.5 squares or 321 acres.

Step 2: Determining Peak Flow If a gauge is installed at the outlet (refer to Fig. 5.5) to record the flow passing through this point over the duration of a storm, the resulting graph (referred to as a hydrograph) would have a shape similar to the one shown in Fig. 5.6. The peak flow (Qp) is highest point on the hydrograph, representing the largest flow rate. This flow occurs at the time to peak (tp) which is the time at which the entire watershed is contributing to the runoff.
160

140

120

Flow (ft3/s)

100

80

60

Qp

40

20

0

0

24

48

72

96

120

144

168

192

tp

Time (hr)

Figure 5.6. Example Hydrograph.

There are several commonly used methods for determining peak runoff. The primary differences between each method relates to: i) the assumptions inherent to each method and ii) the required data (slope, vegetation cover, etc.). Accordingly, the methods presented in this manual (and used within the toolkit) where selected based on their wide acceptance and ease of use. While these methods are acceptable for an initial estimate of culvert or bridge opening sizes, an actual culvert design requires a more detailed hydrologic and hydraulic design as specified in the 2014 GDOT Manual on Drainage Design for Highways.

Method 1: USGS Regression Equations One option for estimating flow is to apply the regression equations developed by the USGS which take into account the watershed and climatic characteristics within 5 hydrologic regions within the state (See Fig. 5. 7). While the USGS has separate equations for rural and urban watersheds (urban watersheds have impervious areas of 10% or greater), because the urban equations can only be applied to 4 regions within Georgia and require parameters such as mean basin slope and percent developed land which are often not readily available, the toolkit uses the equations for rural watersheds. These equations are shown in Table

36

5.1 for eight different return periods (2 500 years) for all five regions within Georgia with watershed areas between 1 and 9,000 miles2. Note that the Table 5.1 equations can only be applied to a watershed that is entirely within one hydrologic region.

Figure 5.7. Map of the Georgia Flood Frequency Regions (USGS, 2008).

Table 5.1. Regression Equations for Estimating Peak Flow in Rural Ungauged Areas that are Entirely Within One Hydrologic Region (USGS, 2009)

Return
Period
(years)
2 5 10 25 50 100 200 500

Regression Equations for Peak Flow (ft3/s) in all Hydrologic Regions

(DA: Drainage area in square miles)

1
158(DA)0.649 295(DA)0.627 398(DA)0.617 537(DA)0.606 661(DA)0.600 776(DA)0.594 891(DA)0.589 1,072(DA)0.583

2
110(DA)0.779 209(DA)0.749 288(DA)0.736 398(DA)0.724 479(DA)0.718 575(DA)0.713 661(DA)0.709 794(DA)0.704

3
25.7(DA)0.758 44.7(DA)0.744 58.9(DA)0.740 77.6(DA)0.736 91.2(DA)0.735 105(DA)0.733 120(DA)0.733 138(DA)0.732

4
60.3(DA)0.649 123(DA)0.627 174(DA)0.617 245(DA)0.606 309(DA)0.600 380(DA)0.594 447(DA)0.589 550(DA)0.583

5
91.2(DA)0.649 200(DA)0.627 295(DA)0.617 447(DA)0.606 575(DA)0.600 724(DA)0.594 891(DA)0.589 1,148(DA)0.583

For watersheds located within multiple regions, the 2009 USGS manual provides a separate set of

37

equations that can be applied. As an example, equations for peak flow for 50 and 100 year storm events are given as:

10 .

.

.

.

.

,

10 .

.

.

.

.

.

.

.

.

.

.

where Qp50, Qp50 = Peak flow for the 50 and 100 year storm event, and PCT1, PCT2, etc. = Basin percentages in hydrologic regions 1, 2, etc. As an example, a 130 miles2 watershed spanning region 2 (90 miles2) and region 3 (40 miles2) would have
PCT1 of 69.2% and PCT2 of 30.8% respectively. Using the equation shown above for the 50 year event, the peak flow would be 9,710 ft3/s.

Method 2: Rational Method For cases in which the watershed is clearly urban and less than 200 acres (0.3 miles2) in area the Rational Method can be applied to estimate peak flow. The area limitation is primarily due to the assumption that the rainfall intensity is constant over the entire basin for a duration of time equal to or greater than the time of concentration. It also assumes that the runoff coefficient (C) is constant during the storm event. The formula estimates the peak flow at any location within the watershed as a function of drainage area, runoff coefficient, and rainfall intensity for a duration equal to the time of concentration (defined as the time required for water to flow from the most remote point in the watershed to the location being analyzed). In equation form:
Qp = CIA where Qp = peak flow (ft3/s); C = runoff coefficient (dimensionless); I = rainfall intensity (in/hr); and A = drainage area (acres).
Runoff Coefficient (C) The runoff coefficient is a unit less number between 0 and 1 that relates the rate of runoff to the total rainfall. The more covered and impervious the land is (such as pavement) the closer to 1 the C value becomes. The coefficient is highly dependent on several factors including: land use, ground slope, topography, and soil factors influencing the rainfall infiltration into the soil. Table 5.2 shows the recommended runoff coefficients for flat, rolling, and hilly terrains. This table corresponds to storms of 5 year to 10 year frequencies. For higher year storms, the coefficients shown in Table 5.2 should be adjusted by multiplying the coefficients by the frequency adjustment factors (fa) shown in Table 5.3. For example, the runoff coefficient for apartment homes located in a flat area for a 50 year storm event would be calculated as:
. 50 1.25 0.625 In cases in which there are several different types of surfaces within the drainage area, a composite (weighted) coefficient can be computed by using the percentages of the different land uses. This is done by using the following equation:

where C1, C2, etc. = runoff coefficients for surface 1, 2, etc.; and A1, A2, etc. = areas 1, 2, etc.

38

Table 5.2. Runoff Coefficients (C) for the Rational Method (GDOT, 2014)

Type of Cover

Flat (0%-2%)

Rolling (2%-10%)

Hilly (Over 10%)

Pavement and Roofs

0.95

0.95

0.95

Earth Shoulders

0.50

0.50

0.50

Drives and Walks

0.75

0.80

0.85

Gravel Pavement

0.50

0.55

0.60

City Business Areas

0.80

0.85

0.85

Suburban Residential

0.25

0.35

0.40

Apartment Homes

0.50

0.60

0.70

Single Family Residential

0.30

0.40

0.50

Lawns, Very Sandy Soil

0.05

0.07

0.10

Lawns, Sandy Soil

0.10

0.15

0.20

Lawns, Heavy (clay) Soil

0.17

0.22

0.35

Grass Shoulders

0.25

0.25

0.25

Side Slopes, Earth

0.60

0.60

0.60

Side Slopes, Turf

0.30

0.30

0.30

Median Areas, Turf

0.25

0.30

0.30

Cultivated Land, Clay and Loam

0.50

0.55

0.60

Cultivated Land, Sand and Gravel

0.25

0.30

0.35

Industrial Areas, Light

0.50

0.70

0.80

Industrial Areas, Heavy

0.60

0.80

0.90

Parks and Cemeteries

0.10

0.15

0.25

Playgrounds

0.20

0.25

0.30

Woodlands and Forests

0.10

0.15

0.20

Meadows and Pasture Land

0.25

0.30

0.35

Pasture with Frozen Ground

0.40

0.45

0.50

Unimproved Areas

0.10

0.20

0.30

Water Surfaces

1.00

1.00

1.00

39

Table 5.3. Frequency Adjustment Factors for Rational Method

(Georgia Stormwater Management Manual, 2001)

Storm Frequency

fa

25 year

1.1

50 year

1.2

100 year

1.25

Rainfall Intensity (I) Rainfall intensity is directly related to both the duration of the storm and the return period (frequency) of the storm event. The Georgia Stormwater Management Manual (GSMM) provides rainfall intensity information for 16 locations across Georgia shown in Fig. 5.8. Table 5.4 shows rainfall intensity data for a one-hour storm duration for 50 year and 100 year frequencies at these 16 sites. For areas not tabulated in Table 5.4, the rainfall intensity charts shown in Figs. 5.9 and 5.10 can be used to extract site-specific intensity data for 50 and 100 year events.

Figure 5.8. Location of the 16 Sites Containing Rainfall Intensity Information (GSMM, 2001). 40

Table 5.4. Rainfall Intensity Information for One Hour Storms Across Georgia (GSMM, 2001)

Rainfall Intensity (in/hr.)

Site

50 yr.

100 yr.

Albany

3.81

4.20

Atlanta

3.30

3.65

Athens

3.36

3.72

Augusta

3.20

3.50

Bainbridge

3.96

4.36

Brunswick

3.75

4.09

Columbus

3.56

3.93

Macon

3.58

3.95

Metro Chattanooga

3.06

3.38

Peachtree City

3.34

3.69

Rome

3.12

3.46

Roswell

3.25

3.59

Savannah

3.96

4.36

Toccoa

3.53

3.93

Valdosta

3.55

3.88

Vidalia

3.83

4.21

41

Figure 5.9. Georgia Rainfall Intensity Data for a One Hour Storm, 50 Year Return Period (NOAA, 2015).
42

Figure 5.10. Georgia Rainfall Intensity Data for a One Hour Storm, 100 Year Return Period (NOAA, 2015).
Step 3: Computing Waterway Area: Having computed the anticipated peak flow (runoff), the waterway area is computed using:
where Qp = peak flow (ft3/s), and V = average velocity (ft/s). For applications involving the flow of water overland or through some form of hydraulic channel, common velocities range from 3 5 ft/s. Compute a waterway area range by using both V = 3 ft/s and V = 5 ft/s. For bridge crossings, this is the required bridge opening area for the 50 year flood.
43

Step 4: Sizing Culverts: Using Table 5.5 for pipe culverts and Table 5.6 for box culverts, the initial culvert size is determined based on the waterway area values computed for both V = 3 and 5 ft/s and then choosing the larger size. Note that the table does not include culvert diameters less than 18 inches since this is the minimum size specified by GDOT (2014). As an example, for a peak flow of 40 ft3/s the computed waterway areas are 13.33 ft2 (for V=3 ft/s) and 8 ft2 (for V=5 ft/s) respectively. Based on these areas, Table 5.5 indicates required pipe culvert diameters of either 54 in or 42 inches, so select 54 inches for an initial sizing. For cases in which site restrictions (example: height from channel bottom to roadway) is not sufficient for a single large culvert, multi-barrel pipe culverts may be applied. Table 5.7 provides equivalent capacities for 2, 3, and 4 multi-barrels culverts.

Table 5.5. Pipe Culvert Sizing Table (Sizes Common for Corrugated Steel Pipe)

Culvert Diameter ( inches )

Waterway Area (ft2)

Diameter of Culvert ( inches )

Waterway Area (ft2)

18

1.767

78

33.183

21

2.405

84

38.484

24

3.142

90

44.179

27

3.976

96

50.265

30

4.909

102

56.745

33

5.94

108

63.617

36

7.069

114

70.882

42

9.621

120

78.540

48

12.566

126

86.590

54

15.904

132

95.033

60

19.635

138

103.869

66

23.758

144

113.097

72

28.274

---

---

44

Table 5.6. Box Culvert Sizing Table (American Concrete Pipe Association, 2015)

Dimensions
ft x ft
4 x 4 5 x 2 5 x 3 5 x 4 5 x 5 6 x 3 6 x 4 6 x 5 6 x 6 7 x 3 7 x 4 7 x 5 7 x 6 7 x 7 8 X 3 8 x 4

Waterway Area (ft2)
15.65 9.50 14.50 19.50 24.50 17.32 23.32 29.32 35.32 20.11 27.11 34.11 41.11 48.11 23.11 31.11

Dimensions
ft x ft
8 x 5 8 x 6 8 x 7 8 x 8 9 x 4 9 x 5 9 x 6 9 x 7 9 x 8 9 x 9 10 x 4 10 x 5 10 x 6 10 x 7 10 x 8 10 x 9

Waterway Area (ft2)
39.11 47.11 55.11 63.11 34.88 43.88 52.88 61.88 70.88 79.88 38.61 48.61 58.61 68.61 78.61 88.61

Dimensions
ft x ft
10 x 10 11 x 4 11 x 6 11 x 8 11 x 9 11 x 10 11 x 11 12 x 4 12 x 5 12 x 6 12 x 7 12 x 8 12 x 9 12 x 10 12 x 11 12 x 12

Waterway Area (ft2)
98.61 42.32 53.32 64.32 97.32 108.32 119.32 46.00 58.00 70.00 82.00 94.00 106.00 118.00 130.00 142.00

Table 5.7. Equivalent Capacities for Multi-barrel Pipe Culverts

Culvert Diameter

Equivalent to

21 in. 24 in.

2 x 18 in. 2 x 18 in.

27 in.

2 x 21 in.

3 x 18 in.

30 in. 33 in.

2 x 24 in. 2 x 24 in.

3 x 18 in. 3 x 21 in.

4 x 18 in. 4 x 18 in.

36 in.

2 x 27 in.

3 x 21 in.

4 x 18 in.

42 in. 48 in.

2 x 30 in. 2 x 36 in.

3 x 27 in. 3 x 30 in.

4 x 21 in. 4 x 24 in.

54 in.

2 x 42 in.

3 x 33 in.

4 x 27 in.

60 in. 66 in.

2 x 48 in. 2 x 48 in.

3 x 36 in. 3 x 42 in.

4 x 30 in. 4 x 36 in.

72 in.

2 x 54 in.

3 x 42 in.

4 x 36 in.

78 in.

2 x 60 in.

3 x 48 in.

4 x 42 in.

84 in. 90 in.

2 x 60 in. 2 x 66 in.

3 x 48 in. 3 x 54 in.

4 x 42 in. 4 x 48 in.

96 in.

2 x 72 in.

3 x 60 in.

4 x 48 in.

102 in. 108 in.

2 x 78 in. 2 x 78 in.

3 x 60 in. 3 x 66 in.

4 x 54 in. 4 x 54 in.

114 in.

2 x 84 in.

3 x 66 in.

4 x 60 in.

120 in. 126 in.

2 x 90 in. 2 x 90 in.

3 x 72 in. 3 x 78 in.

4 x 60 in. 4 x 66 in.

132 in.

2 x 96 in.

3 x 78 in.

4 x 66 in.

138 in. 144 in.

2 x 102 in. 2 x 102 in.

3 x 84 in. 3 x 84 in.

4 x 72 in. 4 x 72 in.

5.6 BRIDGE FOUNDATION INVESTIGATION AND SCOUR For applications in which a bridge crossing is required, a BFI is necessary for the foundation design. The BFI must be performed by a licensed geotechnical engineer in the State of Georgia and contains
45

information collected from borings taken at several points along the proposed bridge location. Borings normally contain information relating to soil types, depth to groundwater, presence of any impenetrable layers (bedrock), and the soil's permeability to water. Aside from providing this baseline information, the BFI also provides design recommendations for different types of foundations including:
Driven piles for pile bents; Caissons (drilled shafts); Spread footings; and Pile footings.
In addition to using information relating to the geotechnical (soil) properties of the bridge site, the bridge foundation design must also take into account the effects of scour. Scour occurs when flowing water removes sediment such as sand a rocks, from bridge abutments or piers. The US Department of Agriculture (USDA) reports that scour is the most common cause of highway bridge failures in the United States (USDA, 1998). GDOT addresses the issue of scour by specifying that foundation depths be based on a 500 year storm event. This depth, referred to the scour depth, can be adjusted based on the findings from the BFI (GDOT, 2015). An estimation of the flow associated with the 500 year storm event can be calculated using the USGS regression equations shown in Table 5.1.
46

CHAPTER 6. CONCEPTUAL COST ESTIMATES
The effort for conceptual cost estimates was concentrated on the unit installed cost approach which combines the cost for time, equipment, manpower, materials, general and project-specific overhead, contingency and profit. A couple of case studies were identified in the literature and the main concern for ABC construction cost estimation was higher cost associated with the projects. This result in higher bid prices due to the complexity of the project and the severity of the time constraints imposed on the contractors. Cost analysis of bridge projects built under Highways for Life (HFL) program, cost premium for deploying ABC ranged from 6 to 21% higher when compared to cost of traditional bridge construction. Also, other cost items that might need to be accounted for would be ancillary items, like railroad flagging, resident engineering time, traffic control devices. Most agencies employ phase-based construction in order to keep traffic flowing through a work zone. Alternatives are considered to close the roadway, establish a detour and build the bridge quickly using ABC method. The additional costs for this process may be offset by the elimination of phased-construction costs. As more ABC projects are built, the costs are trending downward due to construction familiarity with the process which results in lower risks. Road user costs in the work zone are added vehicle operating costs and delay costs to roadway users resulting from construction, maintenance, or rehabilitation activity. They are a function of the timing, duration, frequency, scope, and characteristics of the work zone, the volume and operating characteristics of the traffic affected, and the cost rates assigned to vehicle operations and delays. Overall the conceptual cost estimates are mainly based on specific design, known site conditions, major equipment costs and the probable calculation of user cost savings.
The decision-making matrix described in Chapter 3 and provided in Appendix F may help LGs decide whether to use ABC or conventional construction methods or alternative contracting mechanisms, depending on available funding. A few examples of project costs were initiated corresponding Federal and State requirements to guide LGs in their cost estimation activity; also a short survey was deployed related to conceptual cost estimating activity and major factors impacting cost components for ABC in order to find out how other state DOTs assess cost and its components for ABC. In the followings, contractor cost concerns, cost options, road user costs, and cost accounting options are considered and provided as assistance for local governing bodies in their estimating activity.
6.1 CONTRACTOR COST CONCERNS
Some agencies that have expressed concerns over cost, indicate that they do not see a need to spend extra funds to minimize impacts to the public. In fact, these agencies are already spending additional funds for this purpose. Most agencies employ phased (staged) construction in order to keep traffic flowing through a work zone. It is well known that this construction method is more expensive than construction with a full road closure. The contractors are required to work in a small work zone with adjacent traffic that impedes the work in progress. This approach can increase the cost of the construction. ABC allows owners to take reductions in traffic impacts to the next level by providing even better customer service. In some cases, it may be preferable to close the roadway, establish a detour and build the bridge quickly using ABC. The additional costs of this process may very well be offset by the elimination of phased construction costs. As more ABC projects are built, the costs are trending downward due to construction familiarity with the process which results in lower risks. Risk equates for higher cost in the project.
47

6.2 COST OPTIONS The primary concern for ABC construction cost estimation is the higher cost associated with the projects. This has resulted in higher bid prices due to the complexity of the project and the severity of the time constraints imposed on the contractors. Based on the cost analysis of eight bridge projects built under HFL program, the cost premium for deploying ABC ranged from 6 to 21% higher when compared to the cost of traditional construction. Other cost options that might need to be accounted for would be Ancillary Items. Examples of this would be: railroad flagging, police details, resident engineering time, traffic control devices, etc.
6.3 ROAD USER COSTS Road user costs are costs incurred by a highway network when they are delayed due to construction activities. Road User Costs in the work zone are added vehicle operating costs and delay costs to highway users resulting from construction, maintenance, or rehabilitation activity. They are a function of the timing, duration, frequency, scope, and characteristics of the work zone; the volume and operating characteristics of the traffic affected; and the dollar cost rates assigned to vehicle operations and delays. Daily road user costs (DRUC) are a measure of the daily financial impact of a construction project on the traveling public. The major factors in calculating user costs are out-of-distance travel (OODT), average annual daily traffic (AADT), and average daily truck traffic (ADTT) on the bridge. The Iowa DOT uses the formula:
DRUC ($) = (AADT + 2 ADTT) (OODT) (Mileage Rate)
6.4 SAFETY COSTS Safety costs are estimated based on crash history, exposure times, and traffic maintenance strategies (if the information is available).
6.5 LIFE CYCLE COST ANALYSIS A process for evaluating the total economic worth of a usable project segment by analyzing initial costs and discounted future costs, such as maintenance, user costs, reconstruction, rehabilitation, restoration, and resurfacing costs, over the life of the project segment. Higher quality reduces the need for maintenance and extends the lifespan of the structure. This will lead to a reduced life cycle cost for prefabricated structures.
6.6 COST ACCOUNTING OPTIONS The unit cost approach is a method of accounting that combines the cost for time, equipment, manpower, materials, general and project-specific overhead, contingency and profit.
Cost Based (Bottom-Up Estimating) is a method of accounting that takes into consideration production rates, equipment needs, and manpower for each construction operation.
Appendix E is providing a couple of examples on the conceptual cost estimates with respective major categories of direct costs in both conventional and prefabricated construction. Another example was obtained from an experienced contractor working in one of the northern state and it is a detailed
48

report of cost break down by individual construction items entered the respective bridge replacement job. The job estimate report is presented as a guidance in exhibit E3 of Appendix E.
This section of conceptual cost estimates has a focus in guiding users on which circumstances are most appropriate to use ABC versus conventional bridge construction. Additionally, information on the decision making process for ABC selection can be essentially filtered through the decision-making matrix compiled in Chapter 3. A special survey with essential questions on cost estimation for ABC projects (provided in Appendix E) was deployed to all DOTs that were associated, in multiple occasions, with this type of bridge construction. Separate submissions of the survey were also reaching all other state DOTs. In this final report and to this date, a number of sixteen DOTs responses have been recorded. The effort was closely monitored and a number of iterations of the survey were used in the submission and answers collection process. The results can be used as further guidance to potential users and to complement the decision-making matrix with inclusive items affecting directly the conceptual cost estimates. All the state DOTs responses were recorded in the table belonging to Appendix E, as exhibit E4.
49

CHAPTER 7. TYPICAL CONSTRUCTION PRACTICES
This chapter presents an overview of ABC practices. Over the years, ABC techniques using PBES have become more and more popular throughout the United States. The desire to reduce traffic impacts for commuters has been a high priority in the recent years. Consequently, in the last 20 years, acute traffic control issues at specific job sites has catalyzed the development of what is now known as ABC.
Early ABC projects focused on specific prefabricated elements such as bridge decks and/or pier caps. Bridge deck construction using full depth precast concrete deck panels has been in use for over 20 years. In recent years, use of PBES has spread to all bridge elements, including substructures and foundations. As structural components of a bridge that are built off site, they are crucial strategies to meet ABC objectives. Combining them with the "Fast-Track Contracting" method can generate a fast, highperformance project. PBES components include, but are not limited to:
Precast footings; Precast wing walls; Precast pile foundations; Prefabricated caps and footings; and Prefabricated steel/concrete girder beams.
Benefits of ABC projects using PBES are:
Fewer problems for reduced road user impacts; Improved worker and motorist safety; Expedited project planning process; Improved quality/constructability; and Reduced cost to society.
7.1 ABC CONSTRUCTION CONCEPTS
7.1.1 Prefabricated Spread Footings Precast concrete spread footings are a relatively new concept in bridge construction. These footings were placed over a prepared subgrade on leveling bolts and then grouted into place. The joints between the footing elements are made with shear keys that are filled with non-shrink grout. Although the size of footings for bridge piers can get rather large, the columns for 40, 60, and 80 ft bridge spans will allow for reasonably sized footings which will facilitate their transportation. Reinforcing bars can be extended from the precast footings, and a CIP closure pour can be completed during the erection of the remaining portions of the bridge. For compact bridges, smaller footings can be placed under the columns and extended as the pier structure is being constructed. See Fig. 7.1.
50

Figure 7.1. Example of Precast Spread Footing Plan and Section (MassDOT, 2013).
7.1.2 Precast Pile Cap Footings Precast components can be used for concrete pile caps. Recently, new design details have been developed using corrugated steel pipe voids that are based on research completed in Iowa. Results showed that a void made in a precast concrete footing with a corrugated steel pipe can provide very large punching shear resistance. Research on seismic connections has also demonstrated that these voids can develop large moment resistance as well.
7.1.3 Modular Block Systems Modular block retaining walls are a form of gravity retaining wall in which CIP concrete is replaced by modular reinforced concrete modules that interlock to form a wall (See Fig. 7.2). The mass of the wall
51

and, sometimes, the mass of soil placed within the voids in the blocks. These walls are beneficial to ABC because of the ability to construct them off site and be transported to the site.
Figure 7.2. Modular Block Systems (photo: Redi-Rock.com and ReinforcedEarth.com).
7.1.4 Geosynthetic Reinforced Soil Integrated Bridge System (GRS-IBS) This method combines foundation, abutment, and approach embankment into one composite material. GRS is comprised of many thin layers of soil and geosynthetic reinforcement. The internal soil is retained at the face of the abutment with a high quality concrete block facing. The facing simply retains and prevents erosion of the soil near the face of the wall. The composite mass extends into the embankment which allows the abutment, superstructure, and approach into one unit, and eliminating the differential settlement between the abutment seat and the approach backfill, otherwise known as the bump (Fig. 7.3). This integrated bridge system does not require approach slabs and, consequently, can drastically save the time associated with forming, pouring, and curing concrete for the approach slab.
GRS carries all loads and movements of the superstructure allowing this method to be utilized with concrete precast slabs. This system can be used for 40, 60, and 80 foot bridge spans and presents the following benefits:
Low initial cost; Low life cycle cost; Fast construction; Minimal installation labor and equipment; and No approach slabs needed.
52

Figure 7.3. Typical GRS-IBS Cross Section at the Bridge Abutment (Adams et. al, 2012).
7.1.5 Expanded Polystyrene (EPS) Geofoam for Rapid Embankment Construction EPS geofoam is an embankment fill system comprised of large lightweight blocks (1-2 pounds per cubic foot) of expanded polystyrene. This system is not intended to be a structural support system for the bridge abutment. EPS is used to support bridge abutments by placing the blocks behind a conventional abutment or around piles of integral abutments (See Fig. 7.4). A layer of subbase is required below the pavement to distribute wheel loads. The benefits are:
Fast construction; Extremely lightweight; and Eliminates pre-load settlement times.

(a)

(b)

(c)

Figure 7.4. (a) Bridge abutment with geofoam backfill. (b) EPS geofoam in embankment fill. (c) EPS geofoam for embankment widening (Bartlett et. al., 2000).

53

7.1.6 Abutments or End-Bents Abutments are the substructure at the end of a bridge span on which the superstructure rests. Single-span bridges have abutments at each end, which provide vertical and lateral support for the bridge, as well as acting as retaining walls to resist lateral movement of the earthen fill of the bridge approach (Fig. 7.5). Multi-span bridges require piers to support ends of spans unsupported by abutments.

(a)

(b)

(c)

Figure 7.5. (a) Location of abutments at each end of the bridge (image from Benchmark Hunting Wiki). (b) Integral abutment placed behind a mechanically stabilized earth (MSE) wall (Hailat, 2014). (c) Partial precast end abutment (Hailat, 2014).

7.1.7 Prefabricated Superstructure Elements AASHTO defines a bridge's superstructure as "Structural parts of the bridge that provide the horizontal span." The superstructure can also be defined as the portion of the bridge above the bridge bearings. Superstructure systems include both the deck and primary supporting members integrated in a modular manner such that mobility disruptions occur only as a result of the system being placed. These systems can be rolled, launched, slid, lifted, or transported in place, onto existing or new substructures (abutments and/or piers) that have been built in a manner that does not impact mobility (Fig. 7.6).

Figure 7.6. Prefabricated Superstructure Elements (SHRP2, 2014).
7.1.8 Materials for Prefabricated Bridge Elements This section provides an overview of the many different types of materials used in prefabrication and discusses the impact of the materials on accelerated construction processes. Most agencies have approval processes for prequalification of proprietary materials. Designers should be aware of the materials that are available for use in a particular agency prior to specifying the material.
54

Structural Steel
Steel elements are well suited for prefabrication and accelerated construction. There is a high degree of control over fabrication tolerances, so using steel for connection systems can become easier to use than concrete. Common elements include steel beams and girders, steel grid decks, and steel railings.
An advantage steel possesses over precast concrete is that it typically weighs less than an equivalent concrete element. This is a critical factor to look at when considering shipping and lifting capacities.
Steel has the ability to handle large stress reversals. SPMT could be used to move prefabricated large components. SPMT bridge moves typically induce large stress reversals during lifting and transport that some prestressed concrete beams cannot stand.
Ultra-High Performance Concrete (UHPC)
High performance concrete has emerged in the ABC market in the recent years and combines high quality cement and stone products along with steel or organic fibers. UHPC can achieve very high compressive strengths of 18,000 to 33,000 psi. Not only is it very high in compressive strength, but also very high in flexural strengths between 900 and 7000 psi.
One downside to using UHPC is the high cost of the material compared to the conventional high performance concrete. UHPC has been successfully used on several bridges in the United States for girders and decks on an experimental basis. Even with its high cost, UHPC has a high potential for use in ABC. The high compressive and tensile strength makes the product ideal for closure pour connections between adjacent elements.
Concrete (Normal Weight and Lightweight)
Concrete is a popular and versatile material for prefabrication and ABC projects. The ability to build elements off site, in virtually any shape, makes this material a prime choice for designers. Common prefabricated concrete elements include beams and girders, full depth deck panels, and pier caps. Several states have built entire bridges using precast concrete elements including pier columns, abutment stems, footings, and retaining walls. Concrete can also be used for making connections between different prefabricated bridge elements. These connections often require the use of high early strength concrete to allow for accelerated construction processes.
Durability is a major concern. The new generation of HPC offers durability that exceeds the performance of past concretes. Plant produced precast concrete also has the advantage of being constructed in a controlled environment with higher production and curing standards than normally found in the field. This benefit of higher quality materials of accelerated construction projects is often overlooked or undervalued by designers.
One obstacle to the use of prefabricated concrete elements is the shipping and handling weight. One way to reduce the weight of the elements is to cast voids in the elements during prefabrication. Once in place, the voids can be filled with concrete. The voids can also be used to make connections between
55

elements. A common cost effective way to make voids is to use corrugated steel pipe to form the void. The corrugations are very effective at transmitting very large forces.
Concrete link-slab technology has also been used on ABC projects at bridge piers to make a jointless bridge without live load continuity. The concept with link slabs is to design the connection of the deck across the pier to accommodate the rotation of the beams without significant cracking. This is done by debonding a small portion of the deck near the pier to allow for a wider spread of the rotation strain. That portion (link) is filled with a highly ductile engineered cementitious composite (ECC) material.
Fiber-Reinforced Polymer (FRP)
There has been much research into the use of FRP in recent years. Many states and universities have experimented with these materials. The development of high strength polymers has made the use of FRP materials practical for many bridge applications
7.2 APPLICATION EXAMPLES OF ABC CONSTRUCTION TECHNOLOGIES ABC is most effective for projects that require traffic management. This section will cover how ABC can be applied to the various types of bridge projects that transportation agencies typically manage.
7.2.1 Rehabilitation of Existing Bridges The national bridge inventory is aging; many bridges have deteriorated significantly, especially their superstructure, and concrete deck replacement projects are becoming more common. The supporting girders also experience deterioration due to leaking bridge joints and lack of maintenance.
The substructure is often in better condition when compared to the superstructure. This is especially true for single span bridges and continuous span bridges without deck joints. On many projects, rehabilitation of the substructure combined with replacement of superstructure elements is feasible. The following sections discuss how ABC can be used for the execution for bridge rehabilitation projects.
7.2.2 Deck Replacement Deck replacement is the most common use of ABC. The installation of a bridge deck is time consuming, requiring significant manpower to form it, place reinforcing, cast and cure the concrete, and strip the forms. This labor intensive work is difficult under the best circumstances, but where traffic management is required, it becomes even more complicated.
Three basic forms of ABC deck replacement strategies have been used in the United States. The first is stay-in-place deck forms. They consist of corrugated metal panels designed to support the reinforcing steel and wet concrete of the deck and eliminate the need to strip the forms after the concrete is cured. However, they still require the placement of reinforcing steel and casting and curing of concrete, which does not result in a significant time savings. Also, the underside of the deck cannot be visually inspected in the future.
The second ABC deck replacement strategy is the use of precast and prestressed concrete partial depth deck panels. These panels are typically cast to half the thickness of the finished deck. The remainder of the deck is made up of one layer of steel reinforcement and on-site cast concrete. The panels are designed to span from girder to girder with reinforcement designed to accommodate the positive deck
56

bending moments. Negative deck bending moments are accommodated by the top layer of field placed reinforcement. The advantages and disadvantages of this system are similar to stay-in-place deck forms except that the panel is a structural part of the deck, and is exposed for future visual inspections.
The fastest form of deck placement uses full depth prefabricated deck panels. Different systems have been used in the United States including open grid steel, exodermic deck panels, fiber reinforced polymer panels, and precast concrete panels.
Most ABC projects use precast panels, and they are the focus of this construction manual. Significant research has examined them, including the composite connections between the panel and the girders and the connection between the panels.
7.2.3 Superstructure Replacement The use of ABC for superstructure replacement projects is very common. ABC techniques are particularly well suited for them since the time consuming process of building foundations and substructures is not required. Each state has its own technique to accomplish this type of work in a very short time frame.
Figure 7.7. Self-propelled Modular Transporters (AASHTO, 2006).
Several states have used SPMT technology or lateral skidding/sliding technology to remove and install entire bridge superstructure systems (Fig. 7.7). The new superstructures can be built off site and moved into position in only a few hours.
7.2.4 Substructure Replacement On some bridges, the substructure may be in disrepair due to leaking deck joints and spray from vehicles passing underneath. If abutments have deteriorated, full bridge replacement or abutment patching may be necessary because replacing an abutment is difficult without significant disruption to adjacent areas.
Accelerated replacement of pier columns and caps has more potential. Old pier columns and caps can be removed and replaced with prefabricated pier elements if the footings and foundation are in sound condition and structurally adequate. Closure pours at the base of the columns can be used to connect the old footings to the new pier elements. If an existing pier is supported on a spread footing, the new pier can be built alongside it on rails and jacked into place in a method similar to lateral superstructure skidding/ sliding. Once in place, the footing can be underpinned with grout to seat it on the subgrade.
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7.2.5 Replacement of Existing Bridges and New Bridges Replacing entire bridges and building new bridges differ from deck and superstructure replacement projects because the substructures and foundations must be replaced, which adds a level of complexity. However, ABC methods are often still appropriate.
Replacing a bridge is also different from constructing a new bridge on a new alignment. Often, traffic needs to be accommodated, which requires building the bridge amid and around the traffic or a traffic detour. ABC can minimize the impact of both scenarios. The following sections describe the role that ABC can play in several replacement strategies.
7.2.6 Staging On many projects, traffic needs to be maintained through the construction site at various stages if a suitable detour is unavailable. ABC can be used to minimize the duration of each construction stage. In some cases, complete superstructure prefabrication may not be possible in stage construction projects. Individual prefabricated elements can be used for all portions of the substructures and superstructures.
On any project where staging is being considered, the project team should investigate the potential for changing from staged construction to ABC with full closure with a detour. This approach will offer the greatest opportunity for accelerating the construction since the contractor will have full access to the site for manpower and equipment. It also offers the safest work zone for workers and inspectors.
7.2.7 Full Closure and New Construction On many projects, the entire construction site can be made available to a contractor for the construction of an entire bridge. This occurs on new bridges being built on new roadway alignments, and on bridges that are built with traffic detours.
The previous section outlined the benefits of ABC on projects with detours. Full closure of the bridge offers significant benefits to the ABC process. The use of ABC on projects that involve detours is appropriate if the detour is long or has undesirable geometrics. ABC can be used to minimize the length of time that the detour is in place. Virtually any bridge can be built using ABC methods; however, certain bridge features can have an effect on the ABC process.
7.3 ABC CONSTRUCTION TECHNOLOGIES SHRP2 (2014) provide ABC concepts and sketches for the following technologies:
Above-deck driven carrier systems; Launched temporary truss bridge; Wheeled carriers or SPMTs; Launching and lateral sliding; and Jacking and mining.
This section summarizes these ABC technologies and their advantages and disadvantages to help decision-makers choose the ideal technique for a specific project.
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7.3.1 Above-Deck Driven Carrier (ADDC) Above-deck driven carriers (ADDCs) ride over an existing bridge structure to deliver components. They are ideal where access below the bridge for cranes is limited or the bridge's span is long.
ADDC can be delivered to the construction site shipped on flatbed trucks or towed using mountable axles. Once at the site, they are erected with multiple-axle configurations; after reaching the destination pier, the ADDC is raised to unload the axles. It is then secured and supported at the pier, loaded with gantries, and ready to demolish structure or to deliver girders and slab panels.
On narrow bridges, the ADDC can remove and replace half of the existing structure using counterweights on the gantries. Next, the ADDC can be repositioned over the new half to remove and
replace the remaining old half. For shorter bridge lengths, ADDC can be used to provide access from abutment to abutment. For longer bridge lengths, ADDC can be used to provide access over a
number of spans concurrently, to allow for complete removal and replacement of the exterior portions of multiple spans of an existing structure.
ADDC may not be ideal for highly curved bridges. The stability of the gantry systems must be studied for the weights of the existing slab panels and girders as well as the weights of the new girders and slab panels.
7.3.2 Launched Temporary Truss Bridge Launched temporary truss bridges (LTTBs) are used to transport girders, materials, or equipment over spans, especially when:
Minimal disruption to traffic is desired, Traditional crane access and picks are limited, or Temporary access over waterways is restricted.
LTTBs can be shipped to sites on flatbed trucks or towed with mountable axles. They are erected on site and launched; after reaching the destination pier or temporary bent, they are secured and ready to deliver girders and equipment.
7.3.3 Self-Propelled Modular Transports (SPMTs) SPMTs can be used to remove entire spans or full-length span strips of existing bridges for replacement with new units. They are cost-effective, easily transported, and can be set up and taken down quickly. Trolley movement and steering are governed by hydraulic motors powered by diesel engines. For highway bridge applications, the spans are lighter when made with prestressed concrete and much lighter when made from steel girders and a concrete deck slab. The spans can also be divided into longitudinal strips to diminish the weight to be lifted and the cost of the wheeled carriers.
7.3.4 Launching and Lateral Shifting This method involves building a bridge at a single construction location and launching it incrementally as each section is completed. Prestressed concrete bridges are constructed in a small casting yard behind an abutment. The first bridge segment is equipped with a light steel extension to control the launch stresses. The segment and the steel extension are launched forward onto the piers until it clears the formwork. A
59

second bridge segment is match cast and prestressed against the first one, and the entire bridge section is launched again. This process is repeated until the bridge completed. Similar operations can be applied to steel girder bridges, where the form is replaced with adjustable supports that sustain the girder segments during assembly.
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CHAPTER 8. ABC TOOLKIT Our proposed toolkit has three unique, superior features over other ABC toolkits:

Extensive The proposed toolkit covers, not only design and construction components, but also risk analysis and cost estimation (Table 8.1). These extensive contents assist owners, designers, contractors, and decision-makers to make appropriate decisions, and start ABC projects without any additional resources.

Convenient Enhanced and detailed design examples minimize the need for other design aides such as finite element programs or structural analysis software by providing additional Mathcad design aides to calculate design loadings on superstructures, which help pre-design ABC bridges conveniently.

Current The proposed toolkit includes current state-of-the-art development of ABC applications through comprehensive literature reviews and latest surveys.

Table 8.1. Comparison of the SHRP2 R04 ABC Toolkit and the Proposed Toolkit

ABC Components Decision-Making Tool

Proposed Toolkit
Decision-making matrix Decision-making flowchart

Design

Design concepts Design examples & aides

Construction Risk Analysis Cost Estimates

Construction guidelines Construction flowcharts
Risk analysis guidelines Interactive flowcharts Cost estimates guidelines Examples of cost estimates

Existing SHRP2 R04 Toolkit N/A
Design concepts Design examples Design specifications
(recommendation)
Construction concepts Construction specifications
(recommendation) N/A
N/A

The Components will include the followings:

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ABC decision-making Component ABC design Component
- Design Concepts - Pre-design Examples - Design Aides (Mathcad Examples) to calculate design loadings (moments, shears, and
reactions) ABC Construction Component Hydrological and Hydraulic Component Conceptual Cost Component
The toolkit will be provided in a word-processor format with hyperlinks to referenced sites, or the team will create a template for a web-based system to facilitate ABC design implementation; a final version of the web site can be built from the template. The web site and its server will contain links to the main design documents required for the proper selection of accelerated bridge techniques and a user form generated by a software application for cost analyses.
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CHAPTER 9. SUMMARY AND CONCLUSIONS Accelerated Bridge Construction (ABC) techniques are highly effective in remediating traffic disruptions during bridge renewals, promoting traffic and worker safety, and improving the quality and durability of bridges. However, their higher initial cost has prevented widespread and sustained implementation.
Our survey results revealed that local contractors prefer conventional CIP construction for bridge renewals because modular construction cuts into profits. Furthermore, designers hesitate to risk using new technologies. However, comprehensive national studies of ABC practices found that accumulated experience and repeated use could lead to contractor acceptance as well as savings in construction costs and time.
The primary objective of this study was to develop and deliver a toolkit for accelerated selection and construction of bridges in place using prefabricated modular systems with 40, 60, and 80 ft span lengths for LGs in Georgia. The components of the proposed ABC toolkit address: 1) decision-making; 2) design; 3) construction; 4) risk analysis; and 5) cost estimation. It will be an extensive, convenient source of the latest guidelines for ABC applications. It is not intended for developing final design and construction plans but as a source of information to help decision-makers and owners develop an initial design, estimate the material and construction costs, and determine when and where ABC will be most beneficial. It will provide guidelines to assist LGs and third-party designers in employing GDOT design standards for ABC. With repeated implementation, ABC options will become even more economical and efficient.
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SELECTED BIBLIOGRAPHY
Adams, M., Nicks, J., Stabile, T., Wu, J., Schlatter, W., & Hartmann, J. (2012). Geosynthetic reinforced soil integrated bridge interim implementation guide. Federal Highway Administration Report No. FHWA-HRT-11-026. Available at https://www.fhwa.dot.gov/publications/research/infrastructure/structures/11026/11026.pdf.
American Association of State Highway and Transportation Officials (AASHTO). (2003). Guide specifications for design and construction of segmental concrete bridges. Washington, DC: AASHTO.
AASHTO. (2006). Innovation initiative, SPMT photos. Florida DOT Graves Avenue Bridge over I-4. Available at http://aii.transportation.org/Pages/SPMTPhotos.aspx.
AASHTO. (2012). AASHTO LRFD bridge design specifications, 6th ed, Washington, DC: AASHTO.
AASHTO & FHWA. (2002). Innovative technology for accelerated construction of bridge and embankment foundations. Preliminary summary report. Washington, DC: US Department of Transportation.
American Concrete Industries, (2015). Precast concrete box culverts by ACI. Available at http://americanconcrete.com/commercial/box_culverts/box-culverts.htm.
Bartlett, S., Negussey, D., Kimble, M., & Sheeley, M. (2000). Use of geofoam for I-15 reconstruction in Salt Lake City. Syracuse: Syracuse University Geofoam Research Center. Available at http://geofoam.syr.edu/grc_i15.asp.
Buccola, Greg. (2011). FRP concrete strengthening 101. Louisville, KY: Luckett & Farley Architects, Engineers, & Construction Managers. Available at http://www.luckett-farley.com/frp-strengthening/.
Contech, (2015). Practical factors related to the inspection, evaluation, and load rating of installed culverts. Available at http://www.conteches.com/knowledge-center/pdh-article-series/inspectionevaluation-and-load-rating-of-installe.aspx.
Cranberry Township, (2015). Stormwater management plan. Available at http://www.twp.cranberry.pa.us/index.aspx?NID=1326.
Federal Highway Administration (FHWA). (2007a). FHWA seismic accelerated bridge construction workshop outcomes and follow-up activities final report: Rapid bridge construction: Seismic connections in moderate-to-high seismic zones. San Diego: FHWA.
FHWA. (2007b). Geotechnical engineering circular no. 8: Design and construction of continuous flight auger piles. Washington, DC: US Department of Transportation, FHWA.
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FHWA. (2007c). Manual on use of self-propelled modular transporters to remove and replace bridges. Federal Highway Administration pre- fabricated bridge elements and systems. Available at http://www.fhwa.dot .gov/bridge/pubs/07022.
FHWA. (2008). Bridge deck replacement project using self-propelled modular transporters (SPMTs). Available at http://www.fhwa.dot.gov/bridge/prefab/spmt.cfm, modified May 12, 2008.
FHWA. (2009a). Colorado: Lightning fast construction at Mitchell Gulch. Available at http://www.fhwa.dot.gov/hfl/co2story.pdf.
FHWA. (2009b). Current practices in FRP composites technology: Completed FRP deck projects. Available at http://www.fhwa.dot.gov/bridge/frp/ deckproj.cfm.
FHWA. (2009c). Fiber reinforced polymer composite bridge technology: FRP library. Available at http://www.fhwa.dot.gov/BRIDGE/frp/frppaper.cfm.
FHWA. (2009d). Structures: Prefabricated bridge elements and systems. Bridge deck replacement project using self-propelled modular transporters (SPMTs). Available at http://www.fhwa.dot.gov/bridge/prefab/ spmt.cfm.
FHWA. (2010a). Accelerated bridge construction (ABC) decision making and economic modeling tool. Transportation Pooled Fund Project TPF-5(221), Quarterly Reports. Washington, DC: US Department of Transportation.
FHWA. (2010b). FHWA Resource Center: Innovative contracting solutions: Alternative contracting methods. Available at http://www.fhwa.dot.gov/resourcecenter/teams/construction/cpm_6ics.cfm.
FHWA. (2011). Accelerated bridge construction manual, Publication HIF-12-013. Washington, DC: US Department of Transportation,
FHWA. (2013). Framework for prefabricated bridge elements and systems: Framework for decisionmaking. Available at http://www.fhwa.dot.gov/bridge/ prefab/framework.cfm.
FHWA. (2015). Prefabricated bridge elements and systems (PBES) definitions. Available at https://www.fhwa.dot.gov/bridge/abc/prefab_def.cfm.
Figg, L., & Pate, W. D. (2004). Precast concrete segmental bridges: America's beautiful and affordable icons. PCI Journal, 49, 5, pp. 2638.
Georgia Department of Transportation (GDOT). (2014). Manual on drainage for highways.
GDOT (2015). Bridge and structures design manual.
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Graybeal, B. (2010). Behavior of field-cast ultra-high performance concrete bridge deck connections under cyclic and static structural loading. FHWA-HRT-11-023. Washington DC: US Department of Transportation.
Graybeal, B. (2011). Ultra-high performance concrete. Report FHWA- HRT-11-038. Washington, DC: US Department of Transportation.
Hailat, M. (2014). Integral abutments design and construction considerations. Indiana Department of Transportation, Bridge Division. Available as Integral Abutment Details: Pile to Girder Connection, http://www.iowadot.gov/bridge/abc_ppt_2014.htm.
Massachusetts Department of Transportation (massDOT). (2013). Bridge Design Manual, Part III: Prefabricated Bridge Elements. Available at: https://www.massdot.state.ma.us/highway/DoingBusinessWithUs/ManualsPublicationsForms/LRFDB ridgeManual2013Edition/PartIIandPartIIIStandardDetails/PartIIIPrefabricatedBridgeElements.aspx.
Mistry, V. (2008). Need for prefabricated bridge elements and systems for accelerated bridge construction. WASHTO-X Webinar (17 June).
Ministry for the Environment (2004). Culvert and bridge construction: Guidelines for farmers. Wellington, NZ: Manatu Mo Te Taiao. Available at http://www.mfe.govt.nz/sites/default/files/culvert-bridge-oct04.pdf.
National Cooperative Highway Research Program (NCHRP). (2008). Full-depth precast concrete bridge deck panel systems. NCHRP Report 584. Available at http://www.trb.org/main/blurbs/159669.aspx.
Natural Resources Conservation Service, New Hampshire (2014). Delineating watersheds. Available at http://www.nrcs.usda.gov/wps/portal/nrcs/detail/nh/technical/?cid=nrcs144p2_015680.
Nelson, LeAnne. (2012). Fauntleroy Expressway wearing new jackets... Seattle Department of Transportation. Available at http://sdotblog.seattle.gov/2012/06/21/fauntleroy-expressway-wearingnew-jackets/.
Purdue University, (2005). Culvert design. Available at https://engineering.purdue.edu/~abe527/lectures/culvertdesign.pdf.
Salem, S., & Miller, R. (2006a). Accelerated construction decision-making process for bridges. Madison: Department of Civil and Environmental Engineering, University of Wisconsin, Midwest Regional University Transportation Center.
Salem, S., & Miller, R. (2006b). Accelerated construction decision-making threshold levels. Final report. Cincinnati: Midwest Regional University Transportation Center.
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Strategic Highway Research Program 2 (SHRP2). (2013). Innovative bridge designs for rapid renewal: ABC toolkit. SHRP2 Report S2-R04-RR-2. Washington, DC: Transportation Research Board.
SHRP2. (2014). Innovative bridge designs for rapid renewal, SHRP2 Report S2-R04-RR-1. Washington, DC: Transportation Research Board.
United States Department of Agriculture (USDA). (1998). Bridge scour evaluation: Screening, analysis, & countermeasures. Available at http://www.fs.fed.us/eng/structures/98771207.pdf
United States Geological Survey (USGS). (2009). Magnitude and frequency of rural floods in the southeastern United States, 2006: Volume 1, Georgia. Available at http://pubs.usgs.gov/sir/2009/5043/pdf/SIR2009_5043_book_508_V2.pdf.
USGS. (2011). Magnitude and frequency of floods for urban and small rural streams in Georgia. Available at http://pubs.usgs.gov/sir/2011/5042.
Utah Department of Transportation (UDOT). (2008a). ABC standards: Full depth precast concrete deck panels. Salt Lake City: UDOT.
UDOT. (2008b). Full depth precast concrete deck panel manual. Salt Lake City: UDOT. UDOT. (2008c). Full depth precast concrete deck panel special provision. Salt Lake City: UDOT. UDOT. (2008d). Innovate 80. Available at http://www. udot.utah.gov/innovate80. UDOT. (2008e). Manual for the moving of Utah bridges using self propelled modular transporters
(SPMTs). Available at http://www.udot.utah.gov/main/uconowner.gf?n=3712960312264389695. UDOT. (2010a). Precast approach slab manual. Salt Lake City: UDOT. UDOT. (2010b). Precast bulb tee girder manual. Salt Lake City: UDOT. UDOT. (2010c). Precast substructure elements manual. Salt Lake City: UDOT.
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LIST OF USEFUL ABC WEBSITES
The following website references include SHRP2 program-related websites (AASHTO, SHRP2, TRB); the ABC-UTC website; the TRB ABC subcommittee website; manuals; individual case-study research; and general data collected on ABC techniques and procedures.
1. http://abc-utc.fiu.edu/index.php/Events/national 2. http://shrp2.transportation.org/Pages/Bridge-Designs-for-Rapid-Renewal.aspx 3. http://www.fhwa.dot.gov/goshrp2/Solutions/all/R04/Toolkit_for_Rapid_Bridge_Construction/ 4. http://www.fhwa.dot.gov/everydaycounts/ 5. http://www.trb.org/Main/Blurbs/168046.aspx 6. http://www.trbaff103.com/ 7. http://www.dot.state.fl.us/structures/edc/Files/PBEDC_CS1_Notes.pdf 8. http://www.woodwardcom.com/wp-content/uploads/2010/07/focus_december2011_www.pdf 9. http://www.fhwa.dot.gov/bridge/pubs/07022/chap07.cfm 10. http://www.precastconcrete.org/seminars/2008/2008-08.pdf 11. http://health.masstopics.com/topic/ac/accelerated-construction-construction-strategies-fhwa-
work-zone.html 12. http://www.roadsbridges.com/sites/default/files/selfhelp.pdf 13. http://www.fhwa.dot.gov/bridge/abc/docs/abcmanual.pdf 14. http://on.dot.wi.gov/dtid_bos/extranet/structures/LRFD/BridgeManual/Ch-07.pdf 15. http://www.udot.utah.gov/main//f?p=100:pg:0::::T,V:2090 16. http://www.pcine.org/cfcs/cmsIT/baseComponents/fileManagerProxy.cfc?method=GetFile&fileI
D=29EA580A-F1F6-B13E-8B386984EA89F68F 17. http://transportation.ky.gov/Structural-Design/Pages/ABC.aspx 18. http://www.oregon.gov/ODOT/HWY/BRIDGE/pages/standards_manuals.aspx 19. http://www.abc.fiu.edu/event-on-06022011/ 20. http://conf.tac-atc.ca/english/resourcecentre/readingroom/conference/conf2010/docs/b2/burak.pdf 21. http://books.google.com/books?id=BCeOAgAAQBAJ&pg=PA205&lpg=PA205&dq=accelerated
+bridge+construction+manual&source=bl&ots=6HBscITYuW&sig=FQNXMeaRLm5Lqy4Sim9 CJUwJJKY&hl=en&sa=X&ei=CTiXU43hHIXlsASh3oHwAw&ved=0CE4Q6AEwCTge#v=one page&q=accelerated%20bridge%20construction%20manual&f=false 22. hftp://mceer.buffalo.edu/OConnor/ftp/7NSC%20papers/Oral%20Papers/150%20White.docx 23. http://www.lrrb.org/media/reports/TRS1203.pdf 24. http://cms.oregon.egov.com/ODOT/TD/TP_RES/docs/Reports/2011/ABC.pdf?ga=t 25. http://www.woodwardcom.com/wp-content/uploads/2010/07/focus_december2011_www.pdf 26. http://www.fhwa.dot.gov/hfl/summary/pdfs/iw_070112.pdf 27. http://www.intrans.iastate.edu/research/documents/research-reports/TR-561 Report Volume 1.pdf 28. http://udot.utah.gov/main/uconowner.gf?n=14572900843381595 29. http://udot.utah.gov/main/uconowner.gf?n=14572709238365034 30. https://www.udot.utah.gov/main/uconowner.gf?n=14572526291351034 31. http://www.udot.utah.gov/main/uconowner.gf?n=3712960312264389695 32. http://books.google.com/books/about/State_of_the_Art_of_Precast_Prestressed.html?id=zYPCYg EACAAJ
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33. https://www.fhwa.dot.gov/publications/research/infrastructure/structures/bridge/12038/12038.pdf 34. http://www.fhwa.dot.gov/research/resources/uhpc/ 35. http://www.fhwa.dot.gov/publications/research/infrastructure/structures/hpc/13060/13060.pdf 36. http://www.fhwa.dot.gov/publications/research/infrastructure/structures/hpc/12042/12042.pdf 37. http://ntl.bts.gov/lib/35000/35400/35413/FHWA-HRT-11-023.pdf 38. http://www.ductal-lafarge.com/SLib/22-FHWA-HRT-06103.pdf 39. http://www.fhwa.dot.gov/bridge/abc/docs/abcmanual.pdf 40. http://www.oregon.gov/ODOT/TD/TP_RES/docs/Reports/2011/ABC.pdf 41. http://www.fhwa.dot.gov/bridge/prefab/if09010/report.pdf 42. http://www.fhwa.dot.gov/bridge/prefab/if06030.pdf 43. http://www.fhwa.dot.gov/bridge/pubs/07022/chap00.cfm 44. http://www.fhwa.dot.gov/bridge/pubs/07022/hif07022.pdf 45. http://ascelibrary.org/doi/abs/10.1061/(ASCE)BE.1943-5592.0000097 46. http://books.google.com/books?hl=en&lr=&id=U0Ra5aukj0sC&oi=fnd&pg=PP1&dq=accelerate
d+bridge+construction+in+the+state+of+georgia&ots=3nzl02Y9pO&sig=xX8NqCPurlGCNTREtwMqynWfeY#v=onepage&q=accelerated%20bridge%20construction%20in%20the %20state%20of%20georgia&f=false 47. http://www.countyengineers.org/events/annualconf/Documents/2013%20Presentations/Accel%20 Bridge%20Construc%20Russell.pdf 48. http://www.edkraemer.com/construction-services/accelerated-bridge-construction-abc/ 49. http://sri.cce.iastate.edu/abc-seismic/
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APPENDIX A SURVEY RESULTS
A-1

APPENDIX A - SURVEY RESULTS

A1- DOT Surveys

State

Past experience with ABC

Level of Acceptance of
ABC

Whether projects engineered by Impediments to DOT's or ABC employment Contractor

Availability of Standardized
elements

Ongoing or

Ongoing or

recent projects recent research

Low, doubtful for

typical bridges but

Alabama

may be successful

Yes, one project in for long structures

the past 5 years

that require

substantial

Contractor

lack of man power, elevated
cost

N/A

repetition of

elements

None

four systems of rapid deck
replacement on structures in the northern region of
the state

Alaska

Yes, several projects in recent
years

Moderate

DOT

High costs, lack of experience, lack of
support

Standardization would help but
training and education would also be required

Most new bridges Most recently,

in Alaska research on an all-

incorporate ABC steel bridge pier

features.

system

Arizona

Yes, one project completed

Moderate

DOT & Contractors

Connection issues, Standardization lack of funding, would help with lack of experience decision making

Bridge replacement project utilizing GRS-IBS and a bridge slide

Pursuing research in using UHPC for
bridge connections.

Arkansas

None

Should be done when it's possible
to reduce costs

California

Yes, 8 projects in the past 5 years

Strong acceptance among engineers when funding is
available

N/A DOT

N/A

N/A

N/A

None

Seismicity,

Standardization

suitable staging in would further

urban areas, cost encourage ABC

I - 40 Marble Wash Bridge, Oakland Bay
Bridge

seismic performance of precast elements

Colorado

Yes, 73 projects that utilize ABC

High acceptance

DOT & Contractors

High cost

Standardization would further encourage ABC

Projects are always ongoing and ABC is a
primary consideration

None

Connecticut

Delaware

Yes, less than 10 in the past 5 years

Good acceptance

DOT & Contractors

Higher costs, extended hours

N/A

None

Florida

Yes, multiple projects in the past
5 years

Not adopted as a standard method but is considered for every project

Contractor

Elements are Lack of staging availale but space for SPMTs, contractors avoid inexperienced precasting since contractors, traffic they make profits maintenance, costs placing steel and
concrete

Graves Avenue Bridge (SPMT
usage)

None None

A-2

State

Past experience with ABC

Level of Acceptance of
ABC

Whether projects engineered by Impediments to DOT's or ABC employment Contractor

Availability of Standardized
elements

Ongoing or

Ongoing or

recent projects recent research

Georgia

Yes, 1 project in the past 5 years

Growing acceptance and
interest

Hawaii

Very experienced, Very high

20 projects using acceptance, lower

ABC techniques cost than cast in

since 2001

place methods

Idaho 2 ongoing projects

Illinois

Yes, multiple Low accpetance

projects in the past because of high

5 years

cost

Contractor DOT DOT DOT

Higher costs, extended hours

N/A

None

standardized prefabricated
elements

Initiatives by governing bodies encourage using ABC techniques just to use them instead of using ABC techniques
where it most makes sense
Higher costs

Yes but ABC should be used when it is most economically
efficient or environmentally
beneficial
Used precast concrete deck
panels
Would help cut costs

None
Northside Blvd I84, Union Pacific
Railroad E. Lateral Canal Bridge, Highway
75 None

None None

Indiana

Yes, 2 projects, one involved sliding

Low acceptance

DOT

Lack of knowledge, cost
efficiency

Availability of standards would make ABC easier

One unspecified project

None

Iowa

Yes, multiple projects over the Good acceptance
past 5 years

DOT

Low traffic volumes, contractors say it's less profitable and more complex

Standar plans and shapes would ease the design process and save money

I-92 Cass County Bridge, US 6 Keg
Creek Bridge (completely prefabricated)

None

Kansas

Unknown but a

Yes, one project in shift to ABC as a

the past 5 years

standard is

doubtful

Kentucky

Louisiana

Extensive experience with
several ABC methods

Widely accepted and currently used

Maine

Yes, several projects over the High accpetance
past 5 years

DOT
DOT DOT

Kansas gets very

low prices on cast-

in-place short span

Methods other bridges that are Project similar to

than design-bid-

very low

Iowa's Keg Creek

build are

maintenance.

project

prohibited by state Kansas is relectant (completely

law

to use

prefabricated)

standardized

prefabricated

elements

precast concrete bridge elements

Precast bridges have a shorter service life than cast in place
bridges

Maree Michael

Common use of precast girders for

Bridge and Creek Bridge (Vermilion

short spans

Parish, LA)

Cost of precasting elements as
opposed to casting in place

Desired standardization for
lower costs

None

None None

A-3

State

Past experience with ABC

Level of Acceptance of
ABC

Whether projects engineered by Impediments to DOT's or ABC employment Contractor

Availability of Standardized
elements

Ongoing or

Ongoing or

recent projects recent research

Maryland

Yes, over 20 projects in the last Good acceptance
5-10 years

Contractors

None; ABC is standard

Standardization may help but ABC is employed where
it makes sense3

Prestressed slab deck replacement
is routine

None

Massachusett s

Yes, one project completed in the
past 5 years

Interested in pilot projects to gain familiarity with ABC techniques

Michigan

Moderate

Some experience acceptance that

within the past could be improved

couple of years

on upon

standardization

Minnesota

Yes, 20 various projects

High

Mississippi

Yes, several reconstruction projects following
Katrina

Low acceptance, timidity about connection durability of
precast columns, profitability of large precast
elements,

Missouri

Yes, multiple ABC methods Good acceptance have been applied.

Montana

None yet, considering a pilot
project

Growing

Nebraska

No experience but elements of bridge Not widely
designs were accepted; no need accelerated

Nevada

Experience utilizing SPMT,
bridge slide technique, and precast arches

Widely accepted when used for the right application

New Hampshire

Yes, several

Accepted but

projects completed contractors are

but DOT interest reluctant to utilize

is low

it

DOT Contractors Contractors
DOT DOT DOT Contractor Contractor Contractor

Lack of familiarity due to
inexperience

Desired to reduce customization

I-93 Fast 14 (Salem St, Boston)

None

Cost,

constructability, quality/performan

N/A

ce issues

None

None

Reduced time frame results in overworked and fatigued staff, decision making
process

Stadardization may not help because all tools are created at home in the state

Full depth precast deck with
superstructure lateral slide

NCHRP Project, determining tolerances for
precast elements

Lack of regional consensus, doubts
about joint and connection durability

Local fabricators would embrace new technologies if a commitment to a large number of projects was made

None

Joint and connection durability between precast elements

High cost, seismic durability issues

MSE wall abutments

New Mississippi River Bridge Crossing (St. Louis)

Innovations in substructure construction

Low traffic volume

Highway 89

Pondera County

N/A

South Fork/Dry

GRS-IBS

Fork Marias River

Crossing

Standardization is

High cost, precast elements would
need to get subcontracted

seen as a way to reduce costs and
increase the quality and durability of

finished projects

use of precast

deck panels, heavy

N/A

lifting of remotely

assembled

superstructure

Questionable efficiency

More durable

Unspecified

ABC connection projects involving

details would be

GRS-IBS

beneficial because abutments and

of Nevada's high fully prefabricated

seismicity

superstrectures

None

No real impediments, contractors don't want to hire subcontractors to
precast

Extensive use of precast elements

Main Street Bridge (Epping,
NH)

unspecified research being conducted at the University of New
Hampshire

A-4

State

Past experience with ABC

Level of Acceptance of
ABC

Whether projects engineered by Impediments to DOT's or ABC employment Contractor

Availability of Standardized
elements

Ongoing or

Ongoing or

recent projects recent research

New Jersey

Many projects over the past 5
years

Good acceptance but high
reluctance on the thesis that ABC is
too high risk

Yes, 10 projects in New Mexico the past 5 to 10
years

ABC is moderately accepted

New York

Yes, 10 total projects

Gaining acceptance

DOT DOT DOT

DOT and contractors don't think of it to be a solution in many cases, no incentive
to be creative

Precast elements used

Route 70 bridge over the
Manasquan River,

Cost and effectiveness, lack
of contractor experience and knowledge, lack of construction
personnel

Standardization would help

2 projects that utilized full depth
precast deck panels, 1 project
that utilizes precast pier caps, abutment caps,
and wingwalls

None None

Construction costs, lack of staging areas

Precast elements used

Van Wyck Expressway on
Long Island

UHPC research for fatigue in
precast element joints

North Carolina

Several projects over the past Good accpetance
couple of years,

DOT

N/A

MSE abutments,

N/A

Washington Bypass Project

geosynthetic reinforced soil

abutments

North Dakota

None

Low acceptance,

N/A

Contractor

high cost, connection issues

Standardization may help

None

Very little (topics unspecified)

Ohio

Many projects completed in the
past 14 years

High

Oklahoma

Several projects over the past 5 Good acceptance
years

DOT DOT

Connection issues

Standardization is not necessary

Extensive use of precast elements

Highway 51 over Cottonwood Creek
Bridge (Mannford,OK)

Oregon

8 projects in the past couple of
years

Very high

DOT

High cost, seismic connections

UHPC for connections of full depth deck panels

None

Pennsylvania

Yes, several projects over the
past 5 years

Accepted, considered on a project by project
basis

Contractor

Contractors are unwilling to
assume additional risks, low experience,
reluctance to subcontract,

Yes, used precast elements and
launching using SPMTs

None

structural details

Rhode Island

A-5

State

Past experience with ABC

Level of Acceptance of
ABC

Whether projects engineered by Impediments to DOT's or ABC employment Contractor

Availability of Standardized
elements

Ongoing or

Ongoing or

recent projects recent research

South Carolina

Widely accepted,

seen as favorable

South Dakota

Yes

if project

conditions warrant

it

Tennessee

Limited Little experience, acceptance, one project in the always considered
past 5 years in bridge projects but not often used

Texas

Low acceptance because of low
incentives

Utah

Yes, extensive use of ABC
techniques over the past 10 years

High acceptance, standard practice
since 2010

DOT Contractor
DOT

Low traffic volumes that don't balance high cost of ABC methods

Construction of

2001 project over a railroad yard

jointless decks without increasing cost significantly

or at all

Questions about durability of
precast elements, Precast memebers connection issues and elements used with precast decks
to beams

No financial incentive, bridge projects are too
small to sufficiently expose

Only practical for use when lack of access makes cast-
in-place components hard

contractors to the new methods

to construct or when there is a lot

of repetition

None None

None None

No impediments. ABC is standard

Available for use and currently being implemented

Standard current practice

Standards for deck panels, precast
substructures, new presrressed beam sections, seismic
detailing, acceptable deformation limits, connection details and durability

Vermont

Yes, completed 5 projects in the past Good acceptance
5 years

Contractor

Low traffic, user costs don't balance out costs of ABC
methods,

Yes

None

Incentive/dicincen tive clauses to help encourage ABC methods

Virginia

Washington

Yes, several projects that incorporated ABC techniques

Good acceptance

West Virginia

Yes, 5 projects in the past 5 years

Accepted but traffic volume is too low to make it
feasible

Wisconsin

Low acceptance

and support

Just beginning to impliment ABC
practices

because the program is so new,
yet no strong

opposition

DOT DOT Contractor

Completed

projects using

complete

None documented prefabrication or

superstructure and

substructure

elements

Underdeveloped

ABC contracting industry, lack of
heavy lift contractors and

No precasting industry in the
state

local contractors,

None None

None
methods that minimize
environmental disruption

New process, low support and lack
of experience

Precasting available

Re-decking of major structure with full depth
precast deck panels

precast substructure units

A-6

State

Past experience with ABC

Level of Acceptance of
ABC

Whether projects engineered by Impediments to DOT's or ABC employment Contractor

Availability of Standardized
elements

Ongoing or

Ongoing or

recent projects recent research

Wyoming

Yes, several completed projects

Good acceptance, ABC used where
appropriate

Justification of higher costs since
traffic is low

Extensive use of precast decked bulb-tees for country road
bridges

None

None

A-7

A2- ABC Map Map based off 2009 survey results (SHRP2 2013). Displays total completed projects reported.
A-8

Map based off 2015 survey results. Displays total completed projects reported to date. A-9

APPENDIX B ABC Sample Design Examples and Flowcharts:
Using Mathcad
A-10

APPENDIX B - ABC Sample Design Examples and Flowcharts: Using Mathcad The design component of the toolkit is composed of design concepts and examples. This APPENDIX B provides user friendly pre-design examples and interactive design flowcharts with design aides such as Mathcad. Both steel and concrete girder design examples were developed for 40, 60, 80 ft span lengths, and modified to allow for easy understanding. The base design examples were taken from the SHRP 2 document "Innovative Bridge Designs for Rapid Renewal" (SHRP2 2013). Modifications were made to the original design document by using GDOT standard criteria for highway bridges, information obtained from a design example created by the Federal Highway Association, and the latest AASHTO LRFD Bridge Design Specifications, 6th Ed. (2012). All design examples in this project were created using Mathcad, which allows readers such as Georgia city or county engineers to easily follow the extensive procedures involved in ABC bridge design. Simplicity is stressed throughout the examples and even in the standard drawings in this project.
A-11

B1 - Design Flowchart for Concrete Decked Steel Girder and Precast/Prestressed Concrete Girder A-12

B2- Design Examples for Concrete Decked Steel Girder and Precast/Prestressed Concrete Girder Design using Mathcad
1. Concrete decked steel girder examples for 40ft, 60ft, 80ft spans - Steel Girder-80ft.xmcd - Steel Girder-60ft.xmcd - Steel Girder-40ft.xmcd 2. Precast/prestressed concrete girder examples for 40ft, 60ft, 80ft spans - Prestressed Concrete Girder-80ft.xmcd - Prestressed Concrete Girder-60ft.xmcd - Prestressed Concrete Girder-40ft.xmcd Note: The electronic files of these Mathcad examples are provided through an external hard drive or email.
A-13

Summary of changes from SHRP2:
x Adapted the AASHTO LRFD Bridge Design Specifications, 6th Edition (2012) and GDOT Standards x MathCAD Design Aides provided in Appendix of the final report
- Design loadings calucation (moment, shear, and reaction) for girders - Design loadings calucation for deck x List of variable definitions added x Enhanced the descriptions for all design steps x Expansion of detail regarding girder sizing x New cross-section drawings x Load combination explanations x 12 ft travel lanes, 6 ft shoulders and 2% slope from crown to comply with GDOT standards
A-14

File Name: Steel Girder-80 ft.xmcd
CONCRETE DECKED STEEL GIRDER DESIGN FOR ABC
The following example details the design of a steel girder bridge accompanied by precast concrete deck panels. This particular example was created in accordance with Accelerated Bridge Construction (ABC) principles. The example shown here is presented for a Georgia Department of Transportation research endeavour into ABC technology, and is intended to simplify the design procedure of ABC style bridges. This example was taken from the SHRP 2 Manual (S2-R04-RR-2), and modified by a Georgia Southern University research team working for the Georgia Department of Transportation.
Note: These calculations do not consider every aspect of the bridge design process, and should not be condsidered exhaustive.
Note: All user inputs are highlighted in yellow for easy identification.
AASHTO LRFD Bridge Design Specifications (Sixth Edition with 2012 interims) was used to formulate this example. Located throughout this example are direct references to the AASHTO LRFD Bridge Design Specifications, which are found to the right side of their affiliated calculation.
Before beginning this example, a structural modeling program was used to analyze the superstructure. Although the calculations are not shown, the outputs are used for the design moments, shears and reactions in the example. BRIDGE GEOMETRY:

Design member parameters:

Deck Width: Roadway Width: Skew Angle:

wdeck 36ft 2in wroadway 33ft Skew 0deg

Deck Thickness Haunch Thickness Haunch Width Girder Spacing

td 10.5in th 2in wh 10.5in spacingint 2ft 11in spacingext 3ft

C. to C. Piers: C. to C. Bearings Bridge Length:

Length 80ft Lspan 77ft 10in Ltotal 3Length 240 ft

Stringer

W33x118

Stringer Weight

ws1 118plf

Stringer Length

Lstr Length 6in 79.5 ft

Average spacing of adjacent beams. This value is used so that effective deck width is not overestimated.

A-15

TABLE OF CONTENTS: General: 1. Introduction 2. Design Philosophy 3. Design Criteria 4. Material Properties 5. Load Combinations Girder Design: 6. Beam Section Properties 7. Permanent Loads 8. Precast Lifting Weight 9. Live Load Distribution Factors 10. Load Results 11. Flexural Strength 12. Flexural Strength Checks 13. Flexural Service Checks 14. Shear Strength 15. Fatigue Limit States 16. Bearing Stiffeners 17. Shear Connectors Deck Design: 18. Slab Properties 19. Permanent Loads 20. Live Loads 21. Load Results 22. Flexural Strength Capacity Check 23. Longitudinal Deck Reinforcing Design 24. Design Checks 25. Deck Overhang Design Continuity Design: 26. Compression Splice 27. Closure Pour Design
A-16

List of Variable Definitions
A = plan area of ice floe (ft2); depth of temperature gradient (in.) (C3.9.2.3) (3.12.3) AEP = apparent earth pressure for anchored walls (ksf) (3.4.1) AF = annual frequency of bridge element collapse (number/yr.) (C3.14.4) AS = peak seismic ground acceleration coefficient modified by short-period site factor (3.10.4.2) = notional slope of backfill (degrees) (3.11.5.8.1) B = equivalent footing width (ft) (3.11.6.3) Be = width of excavation (ft) (3.11.5.7.2b) BM = beam (width) for barge, barge tows, and ship vessels (ft) (C3.14.5.1) Bp = width of bridge pier (ft) (3.14.5.3) BR = vehicular braking force; base rate of vessel aberrancy (3.3.2) (3.14.5.2.3) b = braking force coefficient; width of a discrete vertical wall element (ft) (C3.6.4) (3.11.5.6) bf = width of applied load or footing (ft) (3.11.6.3) C = coefficient to compute centrifugal forces; constant for terrain conditions in relation to wind approach (3.6.3) (C3.8.1.1) CD = drag coefficient (s2 lbs./ft4) (3.7.3.1) CH = hydrodynamic mass coefficient (3.14.7) CL = lateral drag coefficient (C3.7.3.1) Csm = elastic seismic response coefficient for the mth mode of vibration (3.10.4.2) c = soil cohesion (ksf) (3.11.5.4) cf = distance from back of a wall face to the front of an applied load or footing (ft) (3.11.6.3) D = depth of embedment for a permanent nongravity cantilever wall with discrete vertical wall elements (ft) (3.11.5.6) DE = minimum depth of earth cover (ft) (3.6.2.2) Do = calculated embedment depth to provide equilibrium for nongravity cantilevered with continuous vertical elements by the simplified method (ft) (3.11.5.6) D1 = effective width of applied load at any depth (ft) (3.11.6.3) d = depth of potential base failure surface below base of excavation (ft); horizontal distance from the back of a wall face to the centerline of an applied load (ft) (3.11.5.7.2b) (3.11.6.3) dc = total thickness of cohesive soil layers in the top 100 ft (3.10.3.1) ds = total thickness of cohesionless soil layers in the top 100 ft (3.10.3.1) E = Young's modulus (ksf) (C3.9.5) EB = deformation energy (kip-ft) (C3.14.11) e = eccentricity of load on footing (ft) (3.11.6.3) F1 = lateral force due to earth pressure (kip/ft) (3.11.6.3) F2 = lateral force due to traffic surcharge (kip/ft) (3.11.6.3) f = constant applied in calculating the coefficient C used to compute centrifugal forces, taken equal to 4/3 for load combinations other than fatigue and 1.0 for fatigue (3.6.3) fc = specified compressive strength of concrete for use in design (ksi) (3.5.1) g = gravitational acceleration (ft/s2) (3.6.3) H = ultimate bridge element strength (kip); final height of retaining wall (ft); total excavation depth (ft); resistance of bridge component to a horizontal force (kip) (C3.11.1) (3.11.5.7.1) (3.14.5.4) Hp = ultimate bridge pier resistance (kip) (3.14.5.4) Hs = ultimate bridge superstructure resistance (kip) (3.14.5.4) H1 = distance from ground surface to uppermost ground anchor (ft) (3.11.5.7.1) Hn+1 = distance from base of excavation to lowermost ground anchor (ft) (3.11.5.7.1) h = notional height of earth pressure diagram (ft) (3.11.5.7) heq = equivalent height of soil for vehicular load (ft) (3.11.6.4) IM = dynamic load allowance (C3.6.1.2.5) k = coefficient of lateral earth pressure; number of cohesive soil layers in the top 100 ft (3.11.6.2) (3.10.3.1) ka = coefficient of active lateral earth pressure (3.11.5.1) ko = coefficient of at rest lateral earth pressure (3.11.5.1) kp = coefficient of passive lateral earth pressure (3.11.5.1) ks = coefficient of earth pressure due to surcharge (3.11.6.1) L = perimeter of pier (ft); length of soil reinforcing elements in an MSE wall (ft); length of footing (ft);
A-17

expansion length (in.) (3.9.5) (3.11.5.8) (3.11.6.3) (3.12.2.3) = characteristic length (ft); center-to-center spacing of vertical wall elements (ft) (C3.9.5) (3.11.5.6) m = multiple presence factor; number of cohesionless soil layers in the top 100 ft (3.6.1.1.2) (3.10.3.1) N = average Standard Penetration Test (SPT) blow count (blows/ft) (ASTM D1586) for the upper 100 ft of the soil profile (3.10.3.1)
Nch = average Standard Penetration Test (SPT) blow count (blows/ft) (ASTM D1586) for cohesive soil layers in the upper 100 ft of the soil profile and us for cohesive soil layers (PI > 20) in the top 100 ft ( us method) (3.10.3.1) Nchi = blowcount for a cohesionless soil layer (not to exceed 100 blows/ft in the above expression) (3.10.3.1) Ni = Standard Penetration Test blow count of a layer (not to exceed 100 blows/ft in the above expression). Note that when using Method B, N values are for cohesionless soils and cohesive soil and rock layers within the upper 100 ft Where refusal is met for a rock layer, Nishould be taken as 100 blows/ft (3.10.3.1) Ns = stability number (3.11.5.6) OCR = overconsolidation ratio (3.11.5.2) P = maximum vertical force for single ice wedge (kip); load resulting from vessel impact (kip); concentrated wheel load (kip); live load intensity; point load (kip) (C3.9.5) (3.14.5.4) (C3.6.1.2.5) (C3.11.6.2) (3.11.6.1) Pa = force resultant per unit width of wall (kip/ft) (3.11.5.8.1) PC = probability of bridge collapse (3.14.5) PD = design wind pressure (ksf) (3.8.1.2.1) PGA = peak seismic ground acceleration coefficient on rock (Site Class B) (3.10.2.1) (3.10.4.2) PH = lateral force due to superstructure or other concentrated lateral loads (kip/ft) (3.11.6.3) Ph = horizontal component of resultant earth pressure on wall (kip/ft) (3.11.5.5) PI = plasticity index (ASTM D4318) (3.10.3.1) Pp = passive earth pressure (kip/ft) (3.11.5.4) Pv = vertical component of resultant earth pressure on wall (kip/ft); load per linear foot of strip footing (kip/ft) (3.11.5.5) (3.11.6.3) Pv = load on isolated rectangular footing or point load (kip) (3.11.6.3) p = effective ice crushing strength (ksf); stream pressure (ksf); basic earth pressure (psf); fraction of truck traffic in a single lane; load intensity (ksf) (3.9.2.2) (3.7.3.1) (3.11.5.1) (3.6.1.4.2) (3.11.6.1) pa = apparent earth pressure (ksf); maximum ordinate of pressure diagram (ksf) (3.11.5.3) (3.11.5.7.1) pp = passive earth pressure (ksf) (3.11.5.4) Q = total factored load; load intensity for infinitely long line loading (kip/ft) (3.4.1) (3.11.6.2) Qi = force effects (3.4.1) q = surcharge pressure (ksf) (3.11.6.3) qs = uniform surcharge pressure (ksf) (3.11.6.1) R = radius of curvature (ft); radius of circular pier (ft); seismic response modification factor; reduction factor of lateral passive earth pressure; radial distance from point of load application to a point on the wall (ft); reaction force to be resisted by subgrade below base of excavation (kip/ft) (3.6.3) (3.9.5) (3.10.7.1) (3.11.5.4) (3.11.6.1) (3.11.5.7.1) Sm = shear strength of rock mass (ksf) (3.11.5.6) Su = undrained shear strength of cohesive soil (ksf) (3.11.5.6) Sub = undrained strength of soil below excavation base (ksf) (3.11.5.7.2b) Sv = vertical spacing of reinforcements (ft) (3.11.5.8.1) us = average undrained shear strength in ksf (ASTM D2166 or ASTM D2850) for the upper 100 ft of the soil profile (3.10.3.1) sui = undrained shear strength for a cohesive soil layer (not to exceed 5.0 ksf in the above expression) (3.10.3.1) S1 = horizontal response spectral acceleration coefficient at 1.0-s period on rock (Site Class B) (3.10.2.1) (3.10.4.2) T = mean daily air temperature (F) (C3.9.2.2) TF = period of fundamental mode of vibration of bridge (s) (3.10.2.2) Thi = horizontal load in anchor i (kip/ft) (3.11.5.7.1) Tm = period of vibration for mth mode (s) (3.10.4.2) Tmax = applied load to reinforcement in a mechanically stabilized earth wall (kip/ft) (3.11.5.8.2) TMaxDesign= maximum design temperature used for thermal movement effects (F) (3.12.2.1) (3.12.2.2) (3.12.2.3) TMinDesign = minimum design temperature used for thermal movement effects (F) (3.12.2.1) (3.12.2.2) (3.12.2.3) TS = corner period at which acceleration response spectrum changes from being independent of period to being inversely proportional to period (s) (3.10.4.2) T0 = reference period used to define shape of acceleration response spectrum (s) (3.10.4.2)
A-18

t = thickness of ice (ft); thickness of deck (in.) (3.9.2.2) (3.12.3) V = design velocity of water (ft/s); design impact speed of vessel (ft/s) (3.7.3.1) (3.14.6) VB = base wind velocity taken as 100 mph (3.8.1.1) VDZ = design wind velocity at design Elevation Z (mph) (3.8.1.1) VMIN = minimum design impact velocity taken not less than the yearly mean current velocity for the bridge location (ft/s) (3.14.6) V0 = friction velocity, a meteorological wind characteristic for various upwind surface characteristics (mph) (3.8.1.1) V30 = wind speed at 30.0 ft above low ground or water level (mph) (3.8.1.1) v = highway design speed (ft/s) (3.6.3) s v = average shear wave velocity for the upper 100 ft of the soil profile (3.10.3.1) W = displacement weight of vessel (tonne) (C3.14.5.1) w = width of clear roadway (ft); width of clear pedestrian and/or bicycle bridge (ft); width of pier at level of ice action (ft); specific weight of water (kcf); moisture content (ASTM D2216) (3.6.1.1.1) (3.6.1.6) (3.9.2.2) (C3.7.3.1) (3.10.3.1) X = horizontal distance from back of wall to point of load application (ft); distance to bridge element from the centerline of vessel transit path (ft) (3.11.6.2) (3.14.6) X1 = distance from the back of the wall to the start of the line load (ft) (3.11.6.2) X2 = length of the line load (ft) (3.11.6.2) Z = structure height above low ground or water level > 30.0 ft (ft); depth below surface of soil (ft); depth from the ground surface to a point on the wall under consideration (ft); vertical distance from point of load application to the elevation of a point on the wall under consideration (ft) (3.8.1.1) (3.11.6.3) (3.11.6.2) Z0 = friction length of upstream fetch, a meteorological wind characteristic (ft) (3.8.1.1) Z2 = depth where effective width intersects back of wall face (ft) (3.11.6.3) z = depth below surface of backfill (ft) (3.11.5.1) = constant for terrain conditions in relation to wind approach; coefficient for local ice condition; inclination of pier nose with respect to a vertical axis (degrees); inclination of back of wall with respect to a vertical axis (degrees); angle between foundation wall and a line connecting the point on the wall under consideration and a point on the bottom corner of the footing nearest to the wall (rad); coefficient of thermal expansion (in./in./F) (C3.8.1.1) (C3.9.2.2) (3.9.2.2) (C3.11.5.3) (3.11.6.2) (3.12.2.3) = safety index; nose angle in a horizontal plane used to calculate transverse ice forces (degrees); slope of backfill surface behind retaining wall; {+ for slope up from wall; for slope down from wall} (degrees) (C3.4.1) (3.9.2.4.1) (3.11.5.3)
= slope of ground surface in front of wall {+ for slope up from wall; for slope down from wall} (degrees) (3.11.5.6) = load factors; unit weight of materials (kcf); unit weight of water (kcf); unit weight of soil (kcf) (C3.4.1) (3.5.1) (C3.9.5) (3.11.5.1) s = unit weight of soil (kcf) (3.11.5.1) s = effective soil unit weight (kcf) (3.11.5.6) EQ = load factor for live load applied simultaneously with seismic loads (3.4.1) eq = equivalent-fluid unit weight of soil (kcf) (3.11.5.5) i = load factor (3.4.1) p = load factor for permanent loading (3.4.1) SE = load factor for settlement (3.4.1) TG = load factor for temperature gradient (3.4.1) = movement of top of wall required to reach minimum active or maximum passive pressure by tilting or lateral translation (ft) (C3.11.1) (3.11.5.5) p = constant horizontal earth pressure due to uniform surcharge (ksf) (3.11.6.1) ph = constant horizontal pressure distribution on wall resulting from various types of surcharge loading (ksf) (3.11.6.2) T = design thermal movement range (in.) (3.12.2.3) iH = horizontal stress due to surcharge load (ksf) (3.11.6.3) iv = vertical stress due to surcharge load (ksf) (3.11.6.3) = angle of truncated ice wedge (degrees); friction angle between fill and wall (degrees); angle between foundation wall and a line connecting the point on the wall under consideration and a point on the bottom corner of the footing furthest from the wall (rad) (C3.9.5) (3.11.5.3) (3.11.6.2) i = load modifier specified in Article 1.3.2; wall face batter (3.4.1) (3.11.5.9)
A-19

= angle of back of wall to the horizontal (degrees); angle of channel turn or bend (degrees); angle between direction of stream flow and the longitudinal axis of pier (degrees) (3.11.5.3) (3.14.5.2.3) (3.7.3.2) f = friction angle between ice floe and pier (degrees) (3.9.2.4.1) i = standard deviation of normal distribution (3.14.5.3) iT = tensile strength of ice (ksf) (C3.9.5) = Poisson's Ratio (dim.) (3.11.6.2) = resistance factors (C3.4.1) f = angle of internal friction (degrees) (3.11.5.4)
f = effective angle of internal friction (degrees) (3.11.5.2) r = internal friction angle of reinforced fill (degrees) (3.11.6.3) s = angle of internal friction of retained soil (degrees) (3.11.5.6)

Permanent Loads CR = force effects due to creep DD = downdrag force DC = dead load of structural components and nonstructural attachments DW = dead load of wearing surfaces and utilities EH = horizontal earth pressure load EL = miscellaneous locked-in force effects resulting from the construction process, including jacking apart of cantilevers in segmental construction ES = earth surcharge load EV = vertical pressure from dead load of earth fill

Transient Loads
EQ = earthquake load FR = friction load IC = ice load IM = vehicular dynamic load allowance LL = vehicular live load LS = live load surcharge PL = pedestrian live load SE = force effect due to settlement TG = force effect due to temperature gradient TU = force effect due to uniform temperature WA = water load and stream pressure WL = wind on live load WS = wind load on structure

1. INTRODUCTION
AASHTO LRFD principles were used in the design of this superstructure. The example is designed for a bridge with three even spans, and has no skew. The bridge has two 12-foot wide lanes and two 6-foot wide shoulders, for a total roadway width of 36' from curb to curb. The bridge deck is precast reinforced concrete with overhangs at the outermost girders. The longitudinal girders are placed as simply supported modules, and made continuous with connection plates and cast-in-place deck joints. The design of the continuity at the deck joint is addressed in final sections of this example.

The cross-section consists of six modules. The interior modules are identical and consist of two steel girders and a 6'-0" precast composite deck slab. Exterior modules include two steel girders and a 6'-1" precast composite deck slab, with F-shape barriers. Grade 50 steel is used throughout, and the deck concrete has a compressive strength of 5,000 psi.
A-20

The closure pour joints between the modules use Ultra High Performance Concrete with a strength of 21,000 psi.
Steel girder design steps, including constructability checks, fatigue design for infinite fatigue lift (unless otherwise noted), and bearing stiffener design comprise the majority of the example. Diaphragm and deck design procedures are present, but not detailed.

Tips for reading this Design Example:

This calculation was prepared with Mathcad version 14. Mathcad was used in this instance to provide a clear representation of formulas, and their execution. Design software other than Mathcad is recommended for a speedier and more accurate design.

Mathcad is not a design software. Mathcad executes user mathematical and simple logic commands.

Example 1: User inputs are noted with dark shaded boxes. Shading of boxes allows the user to easily find the location of a desired variable. Given that equations are written in mathcad in the same fashion as they are on paper, except that they are interactive, shading input cells allows the user to quicly locate inputs amongst other data on screen. Units are user inputs.

Height of Structure:

Hstructure 25ft

Example 2: Equations are typed directly into the workspace. Mathcad then reads the operators and executes the calculations.

Panels are 2.5'

Npanels

Hstructure 2.5ft

Npanels 10

Example 3: If Statements are an important operator that allow for the user to dictate a future value with given parameters. They are marked by a solid bar and operate with the use of program specific logic commands.

Operator offers discount per volume of panels

Discount

.75 if Npanels t 6 .55 if Npanels t 10

Discount 0.6

1 otherwise
Example 4: True or False Verification Statements are an important operator that allow for the user to verify a system criteria that has been manually input. They are marked by lighter shading to make a distinction between the user inputs. True or false statements check a single or pairs of variables and return a Zero or One.

Owner to proceed if discounts on retail below 60%

Discount d .55 1

2. DESIGN PHILOSOPHY

The superstructure of the bridge in this example consists of modules, which are two rolled steel girders supporting a bridge deck panel along their length. The girders are assumed to be simply supported under the weight of the deck panels. In each module, one girder is assumed to support half the weight of its respective deck panel.

The barrier wall is added to exterior modules once the deck and girders are joined. When working with the barrier dead load, the weight is assumed to be evenly distributed between the two modules. Under the additional barrier dead load, the girders are again assumed to be simply supported.

Concerning transportation of modules, it is assumed that the deck has reached 28-day concrete strength, and the deck is fully composite with the girders. The self-weight of the module during lifting and placement is assumed as evenly distributed to four pick points (two per girder).

The modules are placed such that there is a bearing on each end and are again simply supported. The continuous span

A-21

configuration, which includes two bearings per pier on either side of the UHPC joints, is analyzed for positive and negative bending and shear (using simple or refined methods). The negative bending moment above the pier is used to find the force couple for continuity design, between the compression plates at the bottom of the girders and the closure joint in the deck.
The deck design utilizes the equivalent strip method.

3. DESIGN CRITERIA
The first step for any bridge design is to establish the design criteria. The following is a summary of the primary design criteria for this design example:

Governing Specifications: AASTHO LRFD Bridge Design Specifications (6th Edition with 2012 interims)

Design Methodology:

Load and Resistance Factor Design (LRFD)

Live Load Requirements: HL-93

S S3.6

Section Constraints:

Wmod.max 200kip Upper limit on the weight of the modules, based on common lifting and transport capabilities without significantly increasing time and/or cost due to unconventional equipment or permits

4. MATERIAL PROPERTIES Structural Steel Yield Strength: Structural Steel Tensile Strength: Concrete 28-day Compressive Strength: Reinforcement Strength: Steel Density: Concrete Density: Modulus of Elasticity - Steel: Modulus of Elasticity - Concrete:
Modular Ratio:
Future Wearing Surface Density: Future Wearing Surface Thickness:

Fy 50ksi

Fu 65ksi

fc 5ksi

fc_uhpc 21ksi

Fs 60ksi

ws 490pcf

wc 150pcf

Es 29000ksi

Ec

33000

wc



1.5

1000pcf

fcksi

n

Es ceil

7

Ec

4286.8 ksi

Wfws 140pcf tfws 2.5in

(Assumed)

STable 6.4.1-1 STable 6.4.1-1 S5.4.2.1 S5.4.3 & S6.10.3.7 STable 3.5.1-1 STable 3.5.1-1
STable 3.5.1-1

5. LOAD COMBINATIONS

A-22

The following load combinations will be used in this design example, in accordance with Table 3.4.1-1.

Strength I--Basic load combination relating to the normal vehicular use of the bridge without wind.

Strength III--Load combination relating to the bridge exposed to wind velocity exceeding 55 mph.

Strength V--Load combination relating to normal vehicular use of the bridge with wind of 55 mph velocity.

Service I--Load combination relating to the normal operational use of the bridge with a 55 mph wind and all loads taken at their nominal values. Also related to deflection control in buried metal structures, tunnel liner plate, and thermoplastic pipe, to control crack width in reinforced concrete structures, and for transverse analysis relating to tension in concrete segmental girders. This load combination should also be used for the investigation of slope stability.

Service II--Load combination intended to control yielding of steel structures and slip of slip-critical connections due to vehicular live load.
Fatigue I--Fatigue and fracture load combination related to infinite load-induced fatigue life.

Strength I = 1.25DC + 1.5DW + 1.75(LL+IM), where IM = 33% Strength III = 1.25DC + 1.5DW + 1.40WS Strength V = 1.25DC + 1.5DW + 1.35(LL+IM) + 0.40WS + 1.0WL, where IM = 33% Service I = 1.0DC + 1.0DW + 1.0(LL+IM) + 0.3WS + 1.0WL, where IM = 33% Service II = 1.0DC + 1.0DW + 1.3(LL+IM), where IM = 33% Fatigue I = 1.5(LL+IM), where IM = 15%

6. BEAM SECTION
Determining the proper girder depth and dimensions is a vital part of any bridge design process. The size of the girder is a major factor in the cost of the bridge. From Table 2.5.2.6.3-1, the suggested minimum overall depth of the composite I-section in a continuous span is equal to 0.032L.
Thus we have, (.032*80ft) = 2.56' = 30.72" (round up to 33", for common sizing)
The following girder dimensions were taken from the AISC Steel Construction Manual (14th Edition).

Determine Beam Section Properties:

Girder

W33x118

btfx ttf

A-23

Top Flange Bottom Flange Web Girder Depth

btf 11.5in bbf 11.5in Dw 31.4in dgird 32.9in

ttf 0.74in tbf 0.74in tw 0.55in

Dw x tw bbfx tbf

Check Flange Proportion Requeirements Met:

btf d 12.0 1 2ttf

btf

t

Dw 6

1

ttf t 1.1tw 1 tbf 3 bbf

0.1 d 12 d 10 1 ttf 3 btf

12

bbf d 12.0 1 2tbf

bbf

t

Dw 6

1

tbf t 1.1tw 1

tbf bbf

12 t 0.3 1 ttf btf

12

Properties for use when analyzing under beam self weight (steel only):

S 6.10.2.2

Atf btfttf

Abf bbftbf

Asteel Abf Atf Aw

Aw Dwtw Asteel 34.3in2

ysteel

Atf



ttf 2



Abf





tbf 2



Dw

ttf



Aw



Dw 2



ttf

Asteel

ysteel 16.4in

Total steel area. Steel centroid from top.

Calculate Iz:

Moment of inertia about Z axis.

Izsteel

twDw3 12



btf ttf 3 12



bbftbf3 12



Aw



Dw 2



ttf



ysteel2

Atf





ysteel



ttf 2 2

Abf





Dw



tbf 2



ttf



y steel 2

Calculate Iy:

Iysteel

Dwtw3 ttfbtf3 tbfbbf3 12

Moment of inertia about Y axis.

Calculate Ix:

Ixsteel

1 3





btf



ttf

3



bbftbf3



Dwtw3

Izsteel 5815.066in4

Iysteel

188.010 in4

Moment of inertia about X axis.

Ixsteel 4.8in4

Asteel 34.3in2

A-24

Composite Section Properties (Uncracked Section - used for barrier dead load and live load positive bending): Determine composite slab and reinforcing properties

Slab thickness assumes some sacrificial thickness; use:
Dt tslab ttf Dw tbf 40.9in

tslab 8in Total section depth

beff spacingint beff 35in

Effective width.

S 4.6.2.6.1 LRFD

btr

beff n

Transformed slab width as steel.

Izslab

btr

tslab3 12

Transformed slab moment of inertia about z axis as steel.

Aslab btrtslab

Transformed slab area as steel.

Slab reinforcement: (Use #5 @ 8" top, and #6 @ 8" bottom; additional bar for continuous segments of #6 @ 12")

Typical Cross Section

Art

0.465

in2 ft



beff

1.4 in2

Cross Section Over Support

Arb

0.66

in2 ft



beff

1.9 in2

Artadd

0.44

in2 ft



beff

1.3 in2

A-25

Ar Art Arb 3.3in2

crt

2.5in



0.625in





5 16

in

cr

Artcrt Arbcrb Ar

4.9 in

3.4 in

Arneg Ar Artadd 4.6in2

crb

tslab



1.75in





6 16



in

5.9 in

ref from top of slab

crneg

Artcrt Arbcrb Artaddcrt
Arneg

4.5 in

Find composite section centroid:

Ax

Asteel

Ar(n n

1)

Aslab

yslab

tslab 2

yst

Atf





ttf 2



tslab



Abf





tbf 2



Dw

ttf



tslab



Aw



Dw 2



ttf



tslab

Asteel

yc

ystAsteel

crAr(n 1) n

Aslabyslab

Ax

yc 13.1in

Calculate Transformed Iz for composite section:

Iz

Izsteel



Asteel

yst



yc

2

Izslab



Aslab

yslab

yc

2

Ar(n n

1)

cr

yc

2

Calculate Transformed Iy for composite section:

ttr

tslab n

Iyslab

ttr b eff 3 12

Transformed slab thickness. Transformed moment of inertia about y axis of slab.

Iy Iysteel Iyslab

Transformed moment of inertia about the y axis (ignoring reinforcement).

Centroid of steel from top of slab.
Centroid of transformed composite section from top of slab.
Transformed moment of inertia about the z axis.

Calculate Transformed Ix for composite section:

Ix

1 3





btf



ttf

3



bbftbf3



Dwtw3



btrtslab3

Transformed moment of inertia about the x axis.

Results: Ax 77.1in2 Iy 4271.3in4

Iz 13940.9in4 Ix 858.2in4

Composite Section Properties (Uncracked Section - used for live load negative bending):

Find composite section area and centroid:

Axneg

Asteel

Arneg(n n

1)



Aslab

ycneg

ysteelAsteel

crnegArneg(n n

1)



Aslabyslab

Axneg

ycneg 9.5in

Centroid of transformed composite section from top of slab.

A-26

Calculate Transformed Izneg for composite negative moment section:

Izneg

Izsteel

Asteel

ysteel

ycneg

2

Izslab

Aslab

yslab

ycneg

2

Arneg(n n

1)

crneg

ycneg

2

Transformed moment of inertia about the z

axis.

Izneg 8989.1in4

Composite Section Properties (Cracked Section - used for live load negative bending):

Find cracked section area and centroid:

Acr ycr

Asteel Arneg 38.9in2
Asteelysteel Arnegcrneg
Acr

15 in

ycrb

Find cracked section moments of inertia and section moduli:

Izcr Izsteel Asteel ysteel ycr 2 Ar cr ycr 2

Izcr

tslab ttf Dw tbf ycr 6222 in4

Iycr Iysteel

Ixcr

1 3





btf



ttf

3



b bf ttf 3



Dwtw3

dtopcr ycr crt

Iycr 188in4 Ixcr 4.8in4 dtopcr 11.6in

25.8 in

dbotcr Stopcr

tslab ttf Dw tbf ycr Izcr dtopcr

Sbotcr

Izcr dbotcr

dbotcr Stopcr

25.8 in 536.6in3

Sbotcr 240.7in3

7. PERMANENT LOADS

Phase 1: Steel girders are simply supported, and support their self-weight plus the weight of the slab. Steel girders in each module for this example are separated by three diaphragms - one at each bearing location, and one at midspan. Other module span configurations may require an increase or decrease in the number of diaphragms.

Wdeck_int wcspacinginttd

Wdeck_int 382.8plf

Wdeck_ext wcspacingexttd

Wdeck_ext 393.8plf

Whaunch wcwhth

Whaunch 21.9plf

Wstringer ws1

Wstringer 118plf

Diaphragms: Diaphragm Weight

MC18x42.7 ws2 42.7plf

Thickness Conn. Plate Width Conn. Plate

tconn

5 in
8

wconn 5in

Diaphragm Length

Wdiaphragm

ws2

Ldiaph 2

Ldiaph 4ft 2.5in

Height Conn. Plate

hconn 28.5in

Wdiaphragm 89.8lbf

A-27

Wconn 2wstconnwconnhconn
WDCpoint Wdiaphragm Wconn 1.05
Equivalent distributed load from DC point loads:

Wconn 50.5lbf

WDCpoint 147.4lbf

wDCpt_equiv

3WDCpoint Lstr

5.6 plf

Interior Uniform Dead Load, Phase 1: Exterior Uniform Dead Load, Phase 1:

WDCuniform1_int Wdeck_int Whaunch Wstringer wDCpt_equiv WDCuniform1_ext Wdeck_ext Whaunch Wstringer wDCpt_equiv

528.2plf 539.2plf

Moments due to Phase 1 DL: Shear due to Phase 1 DL:

MDC1_int(x)

WDCuniform1_intx 2

Lstr



x

VDC1_int(x)

WDCuniform1_int



Lstr 2



x

MDC1_ext(x)

WDCuniform1_extx 2

Lstr



x

VDC1_ext(x)

WDCuniform1_ext



Lstr 2



x

Phase 2: Steel girders are simply supported and composite with the deck slab, and support their self-weight plus the weight of the slab in addition to barriers on exterior modules. Barriers are assumed to be evenly distributed between the two exterior module girders.

Barrier Area

Abarrier 2.89ft2

Barrier Weight

Wbarrier

wcAbarrier 2

Wbarrier 216.8plf

Interior Dead Load, Phase 2:

WDCuniform_int WDCuniform1_int 528.2plf

Exterior Dead Load, Phase 2: WDCuniform_ext WDCuniform1_ext Wbarrier 755.9plf

Moments due to Phase 2 DL: Shear due to Phase 2 DL:

MDC2_int(x)

WDCuniform_intx 2

Lstr



x

VDC2_int(x)

WDCuniform_int



Lstr 2



x

MDC2_ext(x)

WDCuniform_extx 2

Lstr



x

VDC2_ext(x)

WDCuniform_ext



Lstr 2



x

Phase 3: Girders are composite and have been made continuous. Utilities and future wearing surface are applied.

Unit Weight Overlay

wws 30psf

Wws_int wwsspacingint
Wws_ext wws spacingext 1ft 7in

Wws_int 87.5plf Wws_ext 42.5plf

Unit Weight Utilities

Wu 15plf

WDWuniform_int Wws_int Wu WDWuniform_ext Wws_ext Wu Moments due to DW:
Shears due to DW:

WDWuniform_int 102.5plf

WDWuniform_ext 57.5plf

MDW_int(x)

WDWuniform_intx 2

Lstr



x

MDW_ext(x)

WDWuniform_extx 2

Lstr



x

VDW_int(x)

WDWuniform_int





Lstr 2



x

VDW_ext(x)

WDWuniform_ext



Lstr 2



x

A-28

8. PRECAST LIFTING WEIGHTS AND FORCES

This section addresses the construction loads for lifting the module into place. The module is lifted from four points, at some distance, Dlift from each end of each girder.

Distance from end of lifting point:

Dlift 8.75ft

Assume weight uniformly distributed along girder, with 30% Dynamic Dead Load Allowance:

Dynamic Dead Load Allowance:

DLIM 30%

Interior Module: Total Interior Module Weight: Vertical force at lifting point: Equivalent distributed load:
Min (Neg.) Moment during lifting:
Max (Pos.) Moment during lifting:

Wint LstrWDCuniform_int 3WDCpoint 2(1 DLIM) 110.3kip

Flift_int

Wint 4

27.6 kip

wint_IM

Wint 2Lstr

694 plf

Mlift_neg_max_int

wint_IM



Dlift2
2

Mlift_neg_max_int 26.6kipft

Mlift_pos_max_int

0

if

wint_IM

Lstr 8

2Dlift

2



Mlift_neg_max_int



0

wint_IM

Lstr 8

2Dlift

2



Mlift_neg_max_int

Mlift_pos_max_int 306.9kipft

Exterior Module: Total Exterior Module Weight: Vertical force at lifting point: Equivalent distributed load:
Min (Neg.) Moment during lifting:

Wext LstrWDCuniform_ext 3WDCpoint WbarrierLstr 2(1 DLIM) 202.2kip

Flift_ext

Wext 4

50.6 kip

wext_IM

Wext 2Lstr

Mlift_neg_max_ext

1271.7 plf

wext_IM



Dlift2 2

Mlift_neg_max_ext 48.7kipft

A-29

Max (Pos.) Moment during lifting: Mlift_pos_max_ext

0

if

wext_IM

Lstr 8

2Dlift

2



Mlift_neg_max_ext



0

wext_IM

Lstr 8



2Dlift

2



Mlift_neg_max_ext

Max Shear during lifting:

Mlift_pos_max_ext 562.4kipft
Vlift max wext_IMDlift Flift_ext wext_IMDlift

39.4 kip

9. LIVE LOAD DISTRIBUTION FACTORS

These factors represent the distribution of live load from the deck to the girders in accordance with AASHTO Section 4, and assumes the deck is fully continuous across the joints.
Girder Section Modulus: Izsteel 5815.1in4

Girder Area:
Girder Depth:
Distance between centroid of deck and centroid of beam: Modular Ratio:

Asteel 34.3in2 dgird 32.9in

eg

td 2



th

dgird 2

n7

23.7 in

Multiple Presence Factors:

MP1 1.2

MP2 1.0

S3.6.1.1.2-1

Interior Stringers for Moment:
One Lane Loaded: Kg nIzsteel Asteeleg2

175527.9 in4

S4.6.2.2.1-1

Two Lanes Loaded: Governing Factor:

gint_1m

0.06





spacingint 14ft



0.4



spacingint



0.3



Lspan

Kg



0.1

Lspantd3



0.226

gint_2m

0.075





spacingint 9.5ft



0.6



spacingint



0.2



Lspan

Kg 0.1

Lspantd3



0.288

gint_m max gint_1mgint_2m 0.288

Interior Stringers for Shear: One Lane Loaded: gint_1v
Two Lanes Loaded: gint_2v

0.36 spacingint 0.477



25ft

0.2

spacingint





spacingint



2



12ft

35ft

Governing Factor: gint_v max gint_1v gint_2v 0.477
Exterior Stringers for Moment:

0.436

A-30

One Lane Loaded: Use Lever Rule. Wheel is 2' from barrier; barrier is 2" beyond exterior stringer. de 2in

Lspa 4.5ft r Lspa de 2ft 2.7ft

Two Lanes Loaded:

gext_1m

MP1

0.5r Lspa

e2m

0.77 de 9.1ft

0.356 0.7883

Governing Factor:

gext_2m e2mgint_2m 0.227
gext_m max gext_1mgext_2m

0.356

Exterior Stringers for Shear: One Lane Loaded: Use Lever Rule. gext_1v gext_1m

0.356

Two Lanes Loaded:

e2v

0.6 de 10ft

0.62

gext_2v e2vgint_2v 0.269

Governing Factor: gext_v max gext_1vgext_2v 0.356

FACTOR TO USE FOR SHEAR: gv max gint_v gext_v 0.477

FACTOR TO USE FOR MOMENT: gm max gint_mgext_m 0.356

10. LOAD RESULTS

Case 1: Dead Load on Steel Only (calculated in Section 7). Negative moments are zero and are not considered. Because the girder is simply supported, the maximum moment is at x = Lstr/2 and the maximum shear is at x = 0.

Interior Girder

MDC1int

MDC1_int



Lstr 2



417.3kipft

MDW1int 0kipft MLL1int 0kipft

Exterior Girder

VDC1int VDC1_int(0) 21kip

MDC1ext

MDC1_ext

Lstr 2



426kipft

VDW1int 0kip MDW1ext 0kipft

VLL1int 0kip MLL1ext 0kipft

Load Cases:

VDC1ext VDC1_ext(0) 21.4kip

VDW1ext 0kip

VLL1ext 0kipft

M1_STR_I max 1.25MDC1int 1.5MDW1int 1.75MLL1int1.25MDC1ext 1.5MDW1ext 1.75MLL1ext 532.5kipf V1_STR_I max 1.25VDC1int 1.5VDW1int 1.75VLL1int1.25VDC1ext 1.5VDW1ext 1.75VLL1ext 26.8kip

Case 2: Dead Load on Composite Section (calculated in Section 7). Negative moments are zero and are not considered. Again, the maximum moment occur at x = Lstr/2 and the maximum shear is at x = 0.

Interior Girder

MDC2int

MDC2_int



Lstr 2



417.3kipft

MDW2int 0kipft

MLL2int 0kipft

VDC2int VDC2_int(0) 21kip

VDW2int 0kip

VLL2int 0kip

Exterior Girder

MDC2ext

MDC2_ext

Lstr 2



597.2kipft

MDW2ext 0kipft

MLL2ext 0kipft

VDC2ext VDC2_ext(0) 30kip

VDW2ext 0kip

VLL2ext 0kip

Load Cases:
M2_STR_I max 1.25MDC2int 1.5MDW2int 1.75MLL2int1.25MDC2ext 1.5MDW2ext 1.75MLL2ext 746.5kipf

A-31

V2_STR_I max 1.25VDC2int 1.5VDW2int 1.75VLL2int1.25VDC2ext 1.5VDW2ext 1.75VLL2ext 37.6kip

Case 3: Composite girders are lifted into place from lifting points located distance Dlift from the girder edges. Maximum moments and shears were calculated in Section 8.

Interior Girder MDC3int Mlift_pos_max_int 306.9kipft

MDW3int 0kipft

MLL3int 0kipft

MDC3int_neg Mlift_neg_max_int 26.6kipft MDW3int_neg 0kipft MLL3int_neg 0kipft

VDC3int Vlift 39.4kip

VDW3int 0kip

VLL3int 0kip

Exterior Girder MDC3ext Mlift_pos_max_ext 562.4kipft

MDW3ext 0kipft

MLL3ext 0kipft

MDC3ext_neg Mlift_neg_max_ext 48.7kipft MDW3ext_neg 0kipft MLL3ext_neg 0kipft

VDC3ext Vlift 39.4kip

VDW3ext 0kip

VLL3ext 0kip

Load Cases:
M3_STR_I max 1.5MDC3int 1.5MDW3int1.5MDC3ext 1.5MDW3ext 843.6kipft
M3_STR_I_neg max 1.5MDC3int_neg 1.5MDW3int_neg 1.5MDC3ext_neg 1.5MDW3ext_neg
V3_STR_I max 1.5VDC3int 1.5VDW3int1.5VDC3ext 1.5VDW3ext 59.1kip

73kipft

Case 4: Composite girders made continuous. Utilities and future wearing surface are applied, and live load. Maximum

moment and shear results are from a finite element analysis not included in this design example. The live load value

includes the lane fraction calculated in Section 9, and impact.

Governing Loads: MDC4 387kipft

MDW4 52.5kipft

MLL4 537.98kipft

MWS4 0kipft

MW4 0kipft

MDC4neg 483.8kipft MDW4neg 65.6kipft MLL4neg 541.16kipft

MWS4neg 0kipft

MWL4neg 0kipft

VDC 36.3kip

VDW 4.9kip

VLL 107.7kip

Vu 1.25VDC 1.5VDW 1.75VLLgv 142.6kip

Load Cases: M4_STR_I 1.25MDC4 1.5MDW4 1.75MLL4 1504kipft
M4_STR_I_neg 1.25MDC4neg 1.5MDW4neg 1.75MLL4neg 1650.2kipft

M4_STR_III 1.25MDC4 1.5MDW4 1.4MWS4 562.5kipft M4_STR_III_neg 1.25MDC4neg 1.5MDW4neg 1.4MWS4 703.1kipft

M4_STR_V 1.25MDC4 1.5MDW4 1.35MLL4 0.4MWS4 1.0MW4 1288.8kipft M4_STR_V_neg 1.25MDC4neg 1.5MDW4neg 1.35MLL4neg 0.4MWS4neg 1.0MWL4neg 1433.7kipft

M4_SRV_I 1.0MDC4 1.0MDW4 1.0MLL4 0.3MWS4 1.0MW4 977.5kipft M4_SRV_I_neg 1.0MDC4neg 1.0MDW4neg 1.0MLL4neg 0.3MWS4neg 1.0MWL4neg M4_SRV_II 1.0MDC4 1.0MDW4 1.3MLL4 1138.9kipft M4_SRV_II_neg 1.0MDC4neg 1.0MDW4neg 1.3MLL4neg 1252.9kipft

1090.6kipft

A-32

11. FLEXURAL STRENGTH
The flexural resistance shall be determined as specified in LRFD Design Article 6.10.6.2. Determine Stringer Plastic Moment Capacity First.

LFRD Appendix D6 Plastic Moment

Find location of PNA:

Forces:

Prt ArtFs 81.4kip Prb ArbFs 115.5kip

Ps 0.85fcbefftslab 1190kip Pc Fybtfttf 425.5kip

Pw FyDwtw 863.5kip Pt Fybbftbf 425.5kip

A-33

PNApos

"case 1" if Pt Pw t Pc Ps Prt Prb

otherwise
"case 2" if Pt Pw Pc t Ps Prt Prb

otherwise

"case 3"

if Pt Pw Pc


t



crb tslab



Ps



Prt



Prb


otherwise

"case 4"

if Pt Pw Pc Prb


t



crb tslab



Ps



Prt


otherwise

"case 5"

if Pt Pw Pc Prb


t



crt tslab



Ps



Prt


otherwise

"case 6"

if

Pt Pw Pc Prb Prt

t



crt tslab

Ps


"case 7"

if

Pt Pw Pc Prb Prt

d



crt tslab

Ps


otherwise

PNAneg

PNApos "case 2"
"case 1" if Pc Pw t Pt Prt Prb "case 2" if Pt Pw Pc t Prt Prb otherwise

PNAneg "case 1"

Calculate Y, Dp, and Mp:

D Dw

ts tslab

Case I : Plastic Nuetral Axis in the Steel Web

Y1

D





Pt



Pc



Ps



Prt



Prb



1

2

Pw



th 0

Crt crt Crb crb

DP1 ts th ttf Y1

MP1

Pw
2D

Y12



D



Y1

2



PsPcY1Y1

ts 2



ttf



th



Prt

ts



Crt



ttf 2



Pt



D



Y1

tbf 2



ttf



Y1



th

Prb ts Crb ttf Y1 th



Y1neg



D 2



1



Pc

Pt

Prt Pw

Prb


Dp1neg ts th ttf Y1neg

DCP1neg



D 2Pw





Pt



Pw



Prb



Prt



Pc

A-34

Mp1neg




Pw 2D

Pt



D

Y1neg2
Y1neg



Dw Y1neg 2 Prt ts Crt ttf Y1neg th

tbf 2



Pc



Y1neg



ttf 2

Prb ts Crb ttf Y1neg th




Case II: Plastic Nuetral Axis in the Steel Top Flange

Y2

ttf





Pw



Pt



Ps



Prt



Prb



1

2

Pc



DP2 ts th Y2

MP2

Pc
2ttf

Y22



ttf



Y2

2



Ps



Y2





Pw



D 2

ts 2 ttf

th Prt ts Crt th Y2



Y2



Pt



D



Y2

tbf 2



Prb
ttf

ts



Crb



th



Y2




Y2neg



ttf 2

1



Pw Pc Prt Prb



Pt



DP2neg ts th Y2neg

DCP2neg D

Mp2neg




Pt 2ttf





Y2neg

2





ttf



Y2neg

2



PrPtwtsttf

Crt

th Y2neg

Y2neg



D 2





Prb

Pc



ts Crb ts th

th Y2neg

Y2neg

ttf 2





Case III: Plastic Nuetral Axis in the Concrete Deck Below the Bottom Reinforcing

Y3

ts


Pc



Pw



Pt Ps



Prt



Prb

DP3 Y3

MP3

Ps
2ts





Y32



Prt Y3 Crt



Pt



D



tbf 2

Prb Crb Y3 ttf ts th



Pc



ttf 2

Y3



ts



th

Y3



Pw



D 2



ttf



th

ts



Y3




Case IV: Plastic Nuetral Axis in the Concrete Deck in the bottom reinforcing layer

Y4 Crb

DP4 Y4

MP4

Ps
2ts





Y42



Prt Y4 Crt



Pt



D



tbf 2



Pc



ttf 2

ttf th



th ts

ts
Y4

Y4



Pw



D 2



ttf



th



ts



Y4




Case V: Plastic Nuetral Axis in the Concrete Deck between top and bot reinforcing layers

Y5

ts


Prb



Pc



Pw Ps



Pt



Prt

DP5 Y5

MP5

Ps
2ts





Y52



Prt Y5 Crt



Pt



D



tbf 2

Prb ts Crb
ttf ts th

Y5 Y5



Pc



ttf 2



ts



th

Y5



Pw



D 2



ttf



th

ts



Y5




A-35

Ypos

Y1 if PNApos = "case 1" Y2 if PNApos = "case 2" Y3 if PNApos = "case 3" Y4 if PNApos = "case 4" Y5 if PNApos = "case 5"

DPpos

DP1 if PNApos = "case 1" DP2 if PNApos = "case 2" DP3 if PNApos = "case 3" DP4 if PNApos = "case 4" DP5 if PNApos = "case 5"

MPpos

MP1 if PNApos = "case 1" MP2 if PNApos = "case 2" MP3 if PNApos = "case 3" MP4 if PNApos = "case 4" MP5 if PNApos = "case 5"

Ypos 0.3in

DPpos 8.3in

MPpos 2793kipft

Dp = distance from the top of slab of composite section to the neutral axis at the plastic moment (neglect positive moment reinforcement in the slab).

Yneg

Y1neg if PNAneg = "case 1" Y2neg if PNAneg = "case 2"

DPneg

Dp1neg if PNAneg = "case 1" DP2neg if PNAneg = "case 2"

MPneg

Mp1neg if PNAneg = "case 1" Mp2neg if PNAneg = "case 2"

Yneg 12.1in

DPneg 20.9in

MPneg 23955kipin

Depth of web in compression at the plastic moment [D6.3.2]:

At bbftbf

Ac btfttf

Dcppos

D FyAt
2



FyAc

0.85fcAslab FyAw



FsAr



1

Dcppos

(0in) if PNApos z "case 1"
(0in) if Dcppos 0
Dcppos if PNApos = "case 1"

Dcppos 0in

Dcpneg

DCP1neg if PNAneg = "case 1" DCP2neg if PNAneg = "case 2"

Dcpneg 19.3in

Positive Flexural Compression Check:

From LRFD Article 6.10.2

Check for compactness:

Web Proportions: Dw d 150 1 tw

Web slenderness Limit:

2 Dcppos d 3.76 Es 1

tw

Fy

S 6.10.6.2.2

Therefore Section is considered compact and shall satisfy the requirements of Article 6.10.7.1.

Mn MPpos if DPpos d 0.1Dt

MPpos 1.07




0.7

DPpos Dt



otherwise

Mn 2592.3kipft

Negative Moment Capacity Check (Appendix A6): Web Slenderness: Dt 40.9in Dcneg Dt ycr tbf 25.1in

2Dcneg 5.7 Es 1

tw

Fy

Moment ignoring concrete:

S Appendix A6 (for skew less than 20 deg).

A-36

Myt FySbotcr 12036.4kipin

Myc

My min MycMyt 12036.4kipin

Web Compactness:

FsStopcr

32194.6kipin

Check for Permanent Deformations (6.10.4.2):
Dn max tslab ttf Dw ycyc tslab ttf 27in

Gov if yc tslab ttf yc crtDn 9.7in

fn

M4_SRV_II_neg

Gov Iz



min

1.0

Fy



1

fn

10.4ksi Steel stress on side of Dn



2

Dn

tw Atf

3.5

Rh

12 3 3
(12 2)

1

rw

5.7

Es Fy



Es



PWdcp

minrw


Dcpneg Dcneg


0.54

Fy
MPneg RhMy





2

0.09



24.8

Web Plastification: Flexure Factor:

2 Dcpneg tw

d PWdcp

0

Rpc

MPneg Myc

0.7

f 1.0

Rpt

MPneg Myt

2

Tensile Limit: Mr_neg_t fRptMyt 1996.3kipft Compressive Limit:

Local Buckling Resistance:

f

bbf 2tbf

7.8

rf

0.95 0.76 Es Fy

19.9

pf

0.38

Es Fy

9.2

Fyresid

max


min


0.7

Fy

Rh

Fy

Stopcr Sbotcr

Fy


0.5

Fy


35.0 ksi

MncLB

RpcMyc if f d pf





RpcMyc1







1



FyresidStopcr f pf

RpcMyc





rf



pf



otherwise

MncLB 1996.3kipft

Lateral Torsional Buckling Resistance:

Lb

Lstr 23

13.2 ft

rt

bbf

121



1 3



Dcnegtw bbftbf



2.7 in

Inflection point assumed to be at 1/6 span

A-37

Lp

1.0rt

Es Fy

64.4 in

h D tbf 32.1in

Cb 1.0

Jb

Dtw3



bbf



tbf

3





1



0.63 tbf





btf



ttf

3





1



0.63 ttf



3

3

bbf

3

btf

4.7 in4

Lr

1.95

rt

Es Fyresid



Jb 1 Sbotcrh

1



6.76

Fyresid

Sbotcrh 2

Es

Jb

266.6in

Fcr

Cb2Es
Lb 2

1



0.078

Jb Sbotcrh



Lb 2
rt



rt

MncLTB

RpcMyc if Lb d Lp

87.5 ksi


minCb1




1



Fyresid Sbotcr RpcMyc





Lb Lr



Lp Lp





Rpc Myc Rpc Myc





if

Lp Lb d Lr

min FcrSbotcr RpcMyc if Lb ! Lr

MncLTB 1390.9kipft
Mr_neg_c fmin MncLBMncLTB 1390.9kipft
Governing negative moment capacity: Mr_neg

min Mr_neg_t Mr_neg_c

1390.9kipft

12. FLEXURAL STRENGTH CHECKS

Phase 1: First, check the stress due to the dead load on the steel section only. (LRFD 6.10.3 - Constructability Requirements

Reduction factor for construction const 0.9

Load Combination for construction Max Moment applied, Phase 1: (at midspan)
Maximum Stress, Phase 1:

1.25MDC

Mint_P1

1.25

MDC1_int



Lstr 2



521.7kipft (Interior)

Mext_P1

1.25

MDC1_ext

Lstr 2



532.5kipft (Exterior)

fint_P1

M int_P1 y steel Izsteel

17.7 ksi

(Interior)

fext_P1

M ext_P1 y steel Izsteel

18.1 ksi

(Exterior)

Stress limits:

fP1_max constFy

fint_P1 d fP1_max 1 fext_P1 d fP1_max 1

Phase 2: Second, check the stress due to dead load on the composite section (with barriers added)

Reduction factor for construction
Load Combination for construction
Max Moment applied, Phase 2: (at midspan)

const 0.9 1.25MDC
M2_STR_I 746.5kipft

A-38

Capacity for positive flexure: Check Moment:

Mn 2592.3kipft M2_STR_I d constMn 1

Phase 3: Next, check the flexural stress on the stringer during transport and picking, to ensure no cracking.

Reduction factor for construction
Load Combination for construction
Loads and stresses on stringer during transport and picking:

const 0.9 1.5MDC when dynamic construction loads are involved (Section 10).
M3_STR_I_neg 73kipft

Concrete rupture stress

fr 0.24 fcksi 0.5ksi

Concrete stress during construction not to exceed:

fcmax constfr 0.5ksi

fcconst

M 3_STR_I_neg y c Izn

fcconst d fcmax 1

0.1 ksi

Phase 4: Check flexural capacity under dead load and live load for fully installed continuous composite girders.

Strength I Load Combination M4_STR_I 1504kipft M4_STR_I d fMn 1

f 1.0

M4_STR_I_neg 1650.2kipft M4_STR_I_neg d Mr_neg 0

Strength III Load Combination M4_STR_III 562.5kipft
M4_STR_III d fMn 1

M4_STR_III_neg 703.1kipft M4_STR_III_neg d Mr_neg 1

Strength V Load Combination

M4_STR_V 1288.8kipft M4_STR_V d fMn 1

M4_STR_V_neg 1433.7kipft M4_STR_V_neg d Mr_neg 0

13. FLEXURAL SERVICE CHECKS Check service load combinations for the fully continuous beam with live load (Phase 4): under Service II for stress limits - M4_SRV_II 1138.9kipft M4_SRV_II_neg 1252.9kipft

under Service I for cracking -

M4_SRV_I_neg 1090.6kipft
Ignore positive moment for Service I as there is no tension in the concrete in this case.

Service Load Stress Limits: Top Flange: ftfmax 0.95RhFy 47.5ksi Bottom Flange: fbfmax ftfmax 47.5ksi Concrete (Negative bending only): fr 0.5ksi
Service Load Stresses, Positive Moment:

A-39

Top Flange: Bottom Flange:

fSRVII_tf

M4_SRV_II

yc tslab Iz

fSRVII_tf d ftfmax 1

5 ksi

fbfs2

M4_SRV_II

tslab ttf Dw tbf yc Iz

fl 0

fbfs2

fl 2

d fbfmax

1

27.2 ksi

Service Load Stresses, Negative Moment:

Top (Concrete):

fcon.neg

M 4_SRV_I_neg y cneg nIzneg

2 ksi

Using Service I Loading

Bottom Flange: Check LL Deflection:

fcon.neg d fr 0

fbfs2.neg

M4_SRV_I_neg tslab ttf Dw tbf ycneg
Izneg

fbfs2.neg d fbfmax 1

45.7 ksi

DT 1.104in

DF

3 12

Lstr

DTDF

0.3 3456.5

from independent Analysis - includes 100% design truck (w/impact), or 25% design truck (w/impact) + 100% lane load Deflection distribution factor = (no. lanes)/(no. stringers)
Equivalent X, where L/X = Deflection*Distribution Factor

Lstr t 800 1 DTDF

14. SHEAR STRENGTH Shear Capacity based on AASHTO LRFD 6.10.9

Nominal resistance of unstiffened web:

Fy 50.0ksi

Dw 31.4in

Vp 0.58FyDwtw 500.8kip

tw 0.6in

v 1.0

k 5

A-40

C1

1.0 if Dw d 1.12 Esk

tw

Fy

1.57





Es

k



if

Dw ! 1.40

Esk

Dw 2 Fy tw

Fy





tw



1.12 Dw tw

Esk Fy


otherwise

Vn C1Vp 500.8kip

Vu d vVn 1

C1 1

15. FATIGUE LIMIT STATES:

Fatigue check shall follow LRFD Article 6.10.5. Moments used for fatigue calculations were found using an outside finite element analysis program.

First check Fatigue I (infinite life); then find maximum single lane ADTT for Fatigue II if needed.

Fatigue Stress Limits:

FTH_1 FTH_2 FTH_3

16ksi 12ksi 10ksi

Category B: non-coated weathering steel Category C': Base metal at toe of transverse stiffener fillet welds Category C: Base metal at shear connectors

Fatigue Moment Ranges at Detail Locations (from analysis):

MFAT_B 301kipft

MFAT_CP 285.7kipft

FATI 1.5

FATII 0.75

Constants to use for detail checks:

ADTTSL_INF_B 860 ADTTSL_INF_CP 660 ADTTSL_INF_C 1290

AFAT_B 120108 AFAT_CP 44108 AFAT_C 44108

MFAT_C 207.1kipft nfat 2 if Lstr d 40ft 1.0 otherwise

Category B Check: Stress at Bottom Flange, Fatigue I

fFATI_B

FATIMFAT_B tslab ttf Dw tbf yc
Iz

fFATI_B d FTH_1 1

fFATII_B

FATII FATI



fFATI_B

5.4 ksi

10.8 ksi

A-41

ADTTSL_B_MAX

ADTTSL_INF_B nfat

if fFATI_B d FTH_1

ADTTSL_B_MAX 860

AFAT_Bksi3 36575nfatfFATII_B3

otherwise

Category C' Check: Stress at base of transverse stiffener (top of bottom flange)

fFATI_CP

FATIMFAT_CP

tslab ttf Dw yc Iz

10 ksi

fFATI_CP d FTH_2 1

fFATII_CP

FATII FATI



fFATI_CP

5 ksi

ADTTSL_CP_MAX

ADTTSL_INF_CP nfat

if fFATI_CP d FTH_2

ADTTSL_CP_MAX 660

AFAT_CPksi3 36575nfatfFATII_CP3

otherwise

Category C Check: Stress at base of shear connectors (top of top flange)

fFATI_C

FATIMFAT_C

yc tslab Iz

1.4 ksi

fFATI_C d FTH_3 1

fFATII_C

FATII FATI



fFATI_C

0.7 ksi

ADTTSL_C_MAX

ADTTSL_INF_C nfat

if fFATI_C d FTH_3

ADTTSL_C_MAX

AFAT_Cksi3 36575nfatfFATII_C3

otherwise

1290

FATIGUE CHECK: ADTTSL_MAX min ADTTSL_B_MAX ADTTSL_CP_MAXADTTSL_C_MAX

Ensure that single lane ADTT is less than ADTTSL_MAX 660 If not, then the beam requires redesign.

A-42

16. BEARING STIFFENERS Using LRFD Article 6.10.11 for stiffeners:

tp

5 in
8

bp 5in

b 1.0

Projecting Width Slenderness Check:

bp d 0.48tp

Es Fy

1

Stiffener Bearing Resistance:

tp_weld



5 16



in

*Check min weld size

Apn 2 bp tp_weld tp

Apn 5.9in2

Rsb_n 1.4ApnFy

Rsb_n 410.2kip

Rsb_r bRsb_n

Rsb_r 410.2kip

RDC 26.721kip RDW 2.62kip RLL 53.943kip

DC_STR_I 1.25 DW_STR_I 1.5 LL_STR_I 1.75

Ru DC_STR_IRDC DW_STR_IRDW LL_STR_IRLL

Ru d Rsb_r 1

Weld Check:

throat

tp_weld

2 2

Lweld Dw 23in

Aeff_weld throatLweld

Fexx 70ksi

e2 0.8

Rr_weld 0.6e2Fexx

Ru_weld

Ru 4Aeff_weld

Ru_weld d Ru_weld 1

Axial Resistance of Bearing Stiffeners:

Aeff 29tw tp tw 2bptp

Leff 0.75Dw

Ixp

29twtw3 tp 2bp tw 3

12

12

Iyp

tw tp 29tw 3 2bptp3

12

12

rp

min IxpIyp
Aeff

Q 1

for bearing stiffeners

c 0.9 Kp 0.75

9tw x tw

bp x tp 9tw x tw

bp x tp

Ru 131.7kip
throat 0.2in Lweld 25.4in Aeff_weld 5.6in2 Rr_weld 33.6ksi Ru_weld 5.9ksi
Aeff 12in2 Leff 23.6in Ixp 61.3in4 Iyp 53.6in4 rp 2.1in

Po QFyAeff 601.9kip

A-43

Pe

2EsAeff



Kp

Leff rp



2

49214.3kip





Po



Pn

0.658 Pe Po

if

Pe

t

0.44

Po

0.877Pe otherwise

Pr cPn

Pr 539kip

Ru d Pr 1

17. SHEAR CONNECTORS:

Shear Connector design to follow LRFD 6.10.10.

Stud Properties:

ds

7 in Diameter 8

hs 6in Height of Stud

cs tslab hs

cs t 2in 1

hs t 4 1 ds

ss 3.5in Spacing

ss t 4ds 1

ns 3 Studs per row

Asc

ds 2 2

btf ss ns 1 ds t 1.0in 1 2

Fu 60ksi

Fatigue Resistance:

Zr

5.5d

s2

kip in2

Zr 4.2kip

Qslab Aslab yc yslab

Vf 47.0kip

Vfat

VfQslab Iz

1.2 kip in

ps

nsZr Vfat

10.3 in

6ds d ps d 24in 1

Strength Resistance:

sc 0.85
fc 5ksi Ec 330000.151.5 fc ksi

4286.8 ksi

Qn min 0.5Asc fcEcAscFu

Qr scQn

Psimple min 0.85fcbefftsFyAsteel

Pcont Psimple min 0.45fcbefftsFyAsteel

nlines

Pcont Qrns

Pn 598.9kip
Asc 0.6in2 Qslab 364.9in3
Qn 36.1kip Qr 30.7kip Psimple 1190kip Pcont 1820kip nlines 19.8

A-44

Find required stud spacing along the girder (varies as applied shear varies)

i 0 23

0.00



1.414



4.947

8.480 12.013

15.546



19.079



22.612

26.145



29.678



33.210

33.917

x



ft

34.624

Vfi

36.037



36.743



40.276

43.809



47.342



50.875

54.408 57.941

61.474



65.007



67.833

61.5



59.2



56.8

54.4 52.0

49.5



47.1



44.7

42.7



40.6



40.6

40.6 kip 40.6

40.6



40.6



42.3

44.2



46.6



49.1

51.5 53.9

56.3



58.7



61.5

0

0 1.6

1 1.5

2 1.5

3 1.4

4 1.4

5 1.3

Vfati

VfiQslab Iz

6 7 8

1.2 1.2 kip
in 1.1

9 1.1

10 1.1

11 1.1

12 1.1

13 1.1

14 1.1

15 ...

0

0 7.8

1 8.2

2 8.5

3 8.9

4 9.3

5 9.8

Pmax

nsZr Vfati

6 7 8

10.2 10.8 in 11.3

9 11.9

10 11.9

11 11.9

12 11.9

13 11.9

14 11.9

15

...

min Pmax 7.8in max Pmax 11.9in

18. SLAB PROPERTIES

This section details the geometric and material properties of the deck. Because the equivalent strip method is used in accordance with AASHTO LRFD Section 4, different loads are used for positive and negative bending.

Unit Weight Concrete Deck Thickness for Design Deck Thickness for Loads

wc 150pcf tdeck 8.0in td 10.5in

tdeck t 7in 1

Rebar yield strength

Fs 60ksi

Strength of concrete

fc 5ksi

Concrete clear cover

Bottom cb 1.0in

cb t 1.0in 1

Top ct 2.5in

ct t 2.5in 1

A-45

Transverse reinforcement

Bottom Reinforcing tb

6 in
8

Bottom Spacing stb 8in

stb t 1.5tb 1.5in 1

Design depth of Bar Girder Spacing

stb d 1.5tdeck 18in 1

Astb

12in tb 2 stb 2

0.7 in2

dtb

tdeck





cb



tb 2

6.6 in

spacingint_max 2ft 11in

spacingext 3 ft

Equivalent Strip, +M

wposM

26 6.6 spacingint_max in



ft



Equivalent Strip, -M

wnegM

48 3.0 spacingint_max in



ft



Once the strip widths are determined, the dead loads can be calculated.

Top Reinforcing Top Spacing

tt

5 in
8

stt 8in

stt t 1.5tt 1.5in 1

stt d 1.5tdeck 18in 1

Astt

12in tt 2 stt 2

0.5 in2

dtt

tdeck





ct



tt 2

5.2 in

wposM 45.3in wnegM 56.8in

19. PERMANENT LOADS

This section calculates the dead loads on the slab. These are used later for analysis to determine the design moments.

Weight of deck, +M

wdeck_pos wctdwposM

wdeck_pos 494.9plf

Weight of deck, -M

wdeck_neg wctdwnegM

wdeck_neg 620.7plf

Unit weight of barrier

wb 433.5plf

Barrier point load, +M

Pb_pos wbwposM

Pb_pos 1.63kip

Barrier point load, -M

Pb_neg wbwnegM

Pb_neg 2.05kip

20. LIVE LOADS

This section calculates the live loads on the slab. These loads are analyzed in a separate program with the permanent

loads to determine the design moments.

Truck wheel load

Pwheel 16kip

Impact Factor

IM 1.33

Multiple presence factors Wheel Loads

MP1 1.2 P1 IMMP1Pwheel

MP2 1.0 P2 IMMP2Pwheel

MP3 0.85 P3 IMMP3Pwheel

P1 25.54kip

P2 21.3kip

P3 18.09kip

21. LOAD RESULTS
The separate MathCAD design aides (available in Appendix of the final report) was used to analyze the deck as an 11-span continuous beam without cantilevered overhangs on either end, with supports stationed at girder locations. The dead and live loads were applied separately. The results are represented here as input values, highlighted.
Design Moments

A-46

Mpos_deck 0.4kipft Mpos_LL 15.3kipft

Mpos 1.25Mpos_deck 1.75Mpos_LL

Mpos 27.3kipft

Mpos_dist

Mpos wposM

Mpos_dist

7.23 kipft ft

Mneg_deck 0.6kipft Mneg_LL 7.8kipft

Mneg 1.25Mneg_deck 1.75Mneg_LL

Mneg 14.4kipft

Mneg_dist

Mneg wnegM

Mneg_dist

3.04 kipft ft

22. FLEXURAL STRENGTH CAPACITY CHECK:

Consider a 1'-0" strip:

b 0.9

b 12in

1 0.85 if fc d 4ksi
0.85 0.05 fc 4 otherwise ksi

1 0.8

Bottom:

ctb

AstbFs 0.85fc1b

1 in

atb 1ctb 0.8in

Mntb Mrtb

Astb b

Fs





dtb



atb 2

bMntb

18.6 kipft ft

20.7 kipft ft

Mrtb t Mpos_dist 1

Top: ctt att

AsttFs 0.85fc1b

0.7 in

1ctt 0.5in

Mntt Mrtt

Astt ft

Fs





dtt



att 2

11.3 kipft ft

bMntt

10.2 kipft ft

Mrtt t Mneg_dist 1

23. LONGITUDINAL DECK REINFORCEMENT DESIGN:

Longitudinal reinforcement
Distribution Reinforcement (AASHTO 9.7.3.2)

lb

5 in
8

slb 12in

Aslb

12in lb 2 slb 2

0.3 in2

A%dist

min

220 spacingint_max

67

ft



100

Adist A%dist Astb 0.4in2

lt

5 in
8

slt 12in

Aslt

12in lt 2 slt 2

0.3 in2

67 % Aslb Aslt t Adist 1

A-47

24. DESIGN CHECKS

This section will conduct design checks on the reinforcing according to various sections in AASHTO LRFD.

CHECK MINIMUM REINFORCEMENT (AASHTO LRFD 5.7.3.3.2):

Modulus of Rupture Section Modulus

fr 0.37 fcksi 0.8ksi

Snc

btdeck2 6

Adeck tdeckb

128 in3 96 in2

Ec 4286.8ksi Es 29000ksi

A-48

ybar_tb

Adeck

tdeck 2



(n



1)Astbdtb

Adeck (n 1)Astb

4.1 in

Unfactored Dead Load Cracking Moment
Minimum Factored Flexural Resistance

ybar_tt

Adeck

tdeck 2



(n

1)Asttdtt

Adeck (n 1)Astt

4 in

Itb

btdeck3 12



Adeck



tdeck 2



ybar_tb2

(n



1)Astb

dtb



ybar_tb

2

538.3in4

Itt

btdeck3 12



Adeck



tdeck 2



ybar_tt2

(n



1)Astt

dtt



ybar_tt

2

515.8in4

Sc_tb

Itb tdeck ybar_tb

138.2in3

Sc_tt

Itt tdeck ybar_tt

130 in3

Mdnc_pos_t

kipft 1.25
ft

Mdnc_neg_t

0.542 kipft ft

Mcr_tb

Sc_tb fr max



ft

Mdnc_pos_t





Sc_tb

Snc



1

Sc_tb

fr

ft

9.5 kipft ft

Mcr_tt

Sc_tt fr max



ft

Mdnc_neg_t





Sc_tt

Snc



1

Sc_tt

fr

ft

9 kipft ft

S 5.7.3.3.2

Mr_min_tb Mr_min_tt

min 1.2Mcr_tb 1.33 Mpos_dist min 1.2Mcr_tt1.33 Mneg_dist

9.6 kipft ft
4 kipft ft

Mrtb t Mr_min_tb 1 Mrtt t Mr_min_tt 1

CHECK CRACK CONTROL (AASHTO LRFD 5.7.3.4): eb 1.0

MSL_pos 29.64kipft

MSL_pos_dist

MSL_pos wposM

fssb

MSL_pos_distbn Itb

dtbybar_tb

dcb

cb

tb 2

1.4 in

7.9 kipft ft
3.1 ksi

et 0.75

MSL_neg 29.64kipft

MSL_neg_dist

MSL_neg wnegM

fsst

MSL_neg_distbn Itt

dttybar_tt

dct

ct

tt 2

2.8 in

6.3 kipft ft
1.2 ksi

sb

1

dcb

0.7 tdeck dcb

1.3

sb

700ebkip sbfssbin



2dcb

171.9in

stb d sb 1

st

1

dct

0.7 tdeck dct

1.8

st

700etkip stfsstin



2dct

245.5in

stt d st 1

A-49

SHRINKAGE AND TEMPERATURE REINFORCING (AASHTO LRFD 5.10.8):

Ast

1.30btdeck kip if 0.11in2 d 1.30btdeck kip d 0.60in2

2 b tdeck Fs in

2 b tdeck Fs in

0.11in2 if 1.30btdeck kip 0.11in2 2 b tdeck Fs in

0.60in2 if 1.30btdeck kip ! 0.60in2 2 b tdeck Fs in

0.1 in2

Astb t Ast 1 Aslb t Ast 1

Astt t Ast 1 Aslt t Ast 1

SHEAR RESISTANCE (AASHTO LRFD 5.8.3.3):

0.9

2

45deg

b 1 ft

dv_tb

max

0.72

tdeck

dtb



atb 2

0.9d

tb

6.2 in

dv_tt

max

0.72

tdeck

dtt



att 2

0.9d

tt

5.8 in

dv min dv_tbdv_tt 5.8in

Vc 0.0316 fcksibdv 9.8kip

Vs 0kip Shear capacity of reinforcing steel

Vps 0kip Shear capacity of prestressing steel
Vns min Vc Vs Vps0.25fcbdv Vps 9.8kip

Vr Vns 8.8kip Total factored resistance

Vus 8.38kip

Total factored load

Vr t Vus 1

DEVELOPMENT AND SPLICE LENGTHS (AASHTO LRFD 5.11):

Development and splice length design follows standard calculations in AASHTO LRFD 5.11, or as dictated by the State DOT Design Manual.

25. DECK OVERHANG DESIGN (AASHTO LRFD A.13.4):

A-50

Deck Properties:

Deck Overhang Length Parapet Properties:

Lo 1ft 9in

Note: Parapet properties are per unit length. Compression reinforcement is ignored.

Cross Sectional Area

Ap 2.84ft2

Height of Parapet

Hpar 2ft 10in

Parapet Weight Width at base

Wpar wcAp 426plf wbase 1ft 5in Average width of wall

wwall

13in 9.5in 2

11.3 in

Height of top portion of parapet Height of middle portion of parapet Height of lower portion of parapet

h1 2ft h2 7in h3 3in

Width at top of parapet

width1 9.5in 9.5in

Width at middle transition of parapet Width at base of parapet

width2 12in 12in width3 1ft 5in 17in

Parapet Center of Gravity

b1 width1

b2 width2 width1

b3 width3 width2

h1

h2

h3

b12 2



1 2



h1

b2



b1



b2 3



CGp

h2

h3 b2

b3





b1



b2 2

b3



1 2



h2

b3



b1



b2

2b3 3

h1

h2

h3

b1

1 2

h1b2



h2 h3 b2 b3



1 2



h2

b3

6.3 in

Parapet Reinforcement Rebar spacing: Rebar Diameter:
Rebar Area:

Vertically Aligned Bars in Wall spa 12in

pa

5 in
8

Ast_p





pa



2

b

2 spa

0.3 in2

Horizontal Bars npl 5

pl

5 in
8

Asl_p

pl 2 2

0.3 in2

Cover:
Effective Depth:
Parapet Moment Resistance About Horizontal Axis:
Depth of Equivalent Stress Block:

cst 3in

dst

wbase

cst

pa 2

13.7 in

ext 1.0

ah

Ast_pFs 0.85fcb

0.4 in

csl 2in pa 2.6in

dsl

wwall

csl

pl 2

8.3 in

S 5.7.3.1.2-4 S 5.7.3.2.3

Moment Capacity of Upper Segment of Barrier (about longitudinal axis):

Average width of section Cover
Depth

w1 cst1
dh1

width1 width2

2 2in

w1

cst1



pa 2

10.7 in 8.4 in

Factored Moment Resistance

Mnh1

ext

Ast_pFs



dh1



ah 2

b

12.7 kipft ft

Moment Capacity of Middle Segment of Barrier (about longitudinal axis):

A-51

Average width of section Cover
Depth
Factored Moment Resistance

w2

width2 width3 2

cst2 3in

14.5 in

dh2

w2

cst2



pa 2

11.2 in

Mnh2

ext

Ast_pFs



dh2



ah 2

b

Parapet Base Moment Resistance (about longitudinal axis):

16.9 kipft ft

development in tension

cst3 3in minc_ta 1.5 if cst3 3pa spa pa 6pa

coverbase_vert 1.2

cst3

pa 2

1.2 otherwise

mdec_ta 0.8 if spa t 6in 0.8

1.0 otherwise

ldb_ta

max


1.25inAst_p fc

Fs kip

0.4pa

Fs ksi

if

pa d

11 in
8



ksi



2.70in Fs ksi
fc

if

pa =

14 in
8

ksi

3.50in Fs ksi
fc ksi

if

pa =

18 in
8

hooked bar developed in tension

ldt_ta lhb_ta

l db_ta minc_ta mdec_ta

38pa fc

10.6 in

ksi

14.4 in

minc 1.2

lap splice in tension

ldh_ta max 6in8paminclhb_ta 12.7in llst_ta max 12in1.3ldt_ta 18.7in

benefit ldt_ta ldh_ta 1.7in

ldev_a

7



13 16

in

Fdev

benefit ldev_a ldt_ta

0.7

Fd 0.75

Distance from NA to Compressive Face

ct_b

FdAst_pFs 0.85fc1b

0.3 in

S 5.7.3.1.2-4

3.3 in

A-52

Depth of Equivalent Stress Block
Nominal Moment Resistance

at 1ct_b 0.3in

Mnt

Fd

Ast_p

Fs



dst



at 2

15.6kipft

S 5.7.3.2.3 S 5.7.3.2.2-1

Factored Moment Resistance

Mcb

ext

Mnt ft

15.6 kipft ft

S 5.7.3.2

Average Moment Capacity of Barrier (about longitudinal axis):

Factored Moment Resistance about Horizontal Axis

Mc

Mnh1h1 Mnh2h2 Mcbh3 h1 h2 h3

13.8 kipft ft

Parapet Moment Resistance (about vertical axis):

Height of Transverse

y1 5in

Reinforcement in Parapet

y2 11.5in

y3 18in

y4 24.5in

y5 31in

Depth of Equivalent Stress a nplAsl_pFs

Block

0.85fcHpar

Concrete Cover in Parapet coverr 2in

Width of Parapet at
Transverse Reinforcement

x1

width3

y1 h3 b3 h2

15.6 in

x2

b1 b2

y2 h3 h2 b2 h1

11.8 in

x3

b1 b2

y3 h3 h2 b2 h1

11.2 in

x4

b1 b2

y4 h3 h2 b2 h1

10.5 in

x5

b1 b2

y5 h3 h2 b2 h1

9.8 in

0.6 in

coverrear

coverr

pa

pl 2

2.9 in

coverbase

cst3



pa

pl 2

3.9 in

coverf 2in

covert

x5 2

4.9 in

coverfront

2in

pa

pl 2

covertop covert 4.9in

Design depth

d1i x1 coverbase 11.6in

d1o x1 coverrear 12.6in

d2i x2 coverfront 8.9in

d2o x2 coverrear 8.9in

d3i x3 coverfront 8.2in

d3o x3 coverrear 8.2in

d4i x4 coverfront 7.6in

d4o x4 coverrear 7.6in

d5i x5 covertop 4.9in

d5o x5 covertop 4.9in

Nominal Moment Resistance - Tension on Inside Face

Mn1i Mn2i

ext Asl_p Fs d 1i



a 2



ext Asl_p Fs d 2i



a 2



208.3kipin 158.1kipin

Mn3i

ext Asl_p Fs d 3i



a 2



145.6kipin

Mn4i

ext Asl_p Fs d 4i



a 2



133.2kipin

A-53

Nominal Moment Resistance - Tension on Outside Face
Vertical Nominal Moment Resistance of Parapet Parapet Design Factors: Crash Level Transverse Design Force

Mn5i

ext Asl_p Fs d 5i



a 2



84.5kipin

Mwi Mn1i Mn2i Mn3i Mn4i Mn5i

Mn1o

extAsl_pFsd1o

a 2



18.9kipft

Mn2o

extAsl_pFsd2o

a 2



13.2kipft

Mn3o

extAsl_pFsd3o

a 2



12.1kipft

Mn4o

extAsl_pFsd4o

a 2



11.1kipft

60.8kipft

Mn5o

extAsl_pFsd5o

a 2



7kipft

Mwo Mn1o Mn2o Mn3o Mn4o Mn5o

62.3kipft

Mw

2Mwi Mwo 3

61.3kipft

CL "TL-4" Ft 13.5kip if CL = "TL-1"
27.0kip if CL = "TL-2" 54.0kip if CL = "TL-3" 54.0kip if CL = "TL-4" 124.0kip if CL = "TL-5" 175.0kip otherwise

54 kip

Lt 4.0ft if CL = "TL-1" 4.0ft if CL = "TL-2" 4.0ft if CL = "TL-3" 3.5ft if CL = "TL-4" 8.0ft if CL = "TL-5" 8.0ft otherwise

3.5 ft

Longitudinal Design Force Fl 4.5kip if CL = "TL-1" 9.0kip if CL = "TL-2" 18.0kip if CL = "TL-3" 18.0kip if CL = "TL-4" 41.0kip if CL = "TL-5"

58.0kip otherwise

Vertical Design Force (Down)

Fv 4.5kip if CL = "TL-1" 4.5kip if CL = "TL-2" 4.5kip if CL = "TL-3" 18.0kip if CL = "TL-4" 80.0kip if CL = "TL-5"

80.0kip otherwise

Critical Length of Yield Line Failure Pattern:

Mb 0kipft

18 kip 18 kip

Ll 4.0ft if CL = "TL-1" 4.0ft if CL = "TL-2" 4.0ft if CL = "TL-3" 3.5ft if CL = "TL-4" 8.0ft if CL = "TL-5" 8.0ft otherwise

3.5 ft

Lv 18.0ft if CL = "TL-1" 18ft 18.0ft if CL = "TL-2" 18.0ft if CL = "TL-3" 18.0ft if CL = "TL-4" 40.0ft if CL = "TL-5" 40.0ft otherwise

A-54

Lc

Lt 2

Lt 2 8Hpar Mb Mw

2

Mc

11.9 ft

S A13.3.1-2

Rw

2 2Lc

Lt 8Mb

8Mw

McLc2 Hpar

T

Rwb

Lc 2Hpar

6.6 kip

116.2kip

S A13.3.1-1 S A13.4.2-1

The parapet design must consider three design cases. Design Case 1 is for longitudinal and transverse collision loads under Extreme Event Load Combination II. Design Case 2 represents vertical collision loads under Extreme Event Load Combination II; however, this case does not govern for decks with concrete parapets or barriers. Design Case 3 is for dead and live load under Strength Load Combination I; however, the parapet will not carry wheel loads and therefore this case does not govern. Design Case 1 is the only case that requires a check.

Design Case 1: Longitudinal and Transverse Collision Loads, Extreme Event Load Combination II

DC - 1A: Inside face of parapet ext 1

DC 1.0

DW 1.0

LL 0.5

S A13.4.1 S Table 3.4.1-1

llip 2in
Adeck_1A tdeck llip wbase

152 in2

wbase 17in Ap 2.8ft2

Wdeck_1A wcAdeck_1A 0.2klf

MDCdeck_1A

DCWdeck_1A

llip

wbase 2

Wpar 0.1 kipft
ft

MDCpar_1A DCWpar llip CGp

0.3 kipft ft

Mtotal_1A Mcb MDCdeck_1A MDCpar_1A

16 kipft ft

0.4 klf

tt_add

5 in
8

stt_add 8in

Astt_p

12in tt 2 12in tt_add 2 stt 2 stt_add 2

0.9 in2

dtt_add

tdeck



ct



tt_add 2

ctt_p

Astt_pFs 0.85fc1b

1.4 in

5.2 in

att_p 1ctt_p 1.1in

Mntt_p

Astt_pFs ft





dtt_add



att_p 2

21.4 kipft ft

Mrtt_p bMntt_p

19.2 kipft ft

AsT Astt Astb 1.1in2

Mrtt_p t Mtotal_1A 1

Pn extAsTFs 67.4kip

Pn t T 1

Mu_1A

Mrtt_p 1



T Pn



17.4 kipft ft

Mu_1A t Mtotal_1A 1

A-55

DC - 1B: Design Section in Overhang

Notes:

Distribution length is assumed to increase based on a 30 degree angle from the face of parapet.

Moment of collision loads is distributed over the length Lc + 30 degree spread from face of parapet to

location of overhang design section.

Axial force of collision loads is distributed over the length Lc + 2Hpar + 30 degree spread from face of

parapet to location of overhang design section.

Future wearing surface is neglected as contribution is negligible.

Adeck_1B tdeckLo 168in2

Ap 2.8ft2

Wdeck_1B wcAdeck_1B 0.2klf

Wpar

MDCdeck_1B

DC

Wdeck_1B

Lo 2

0.2 kipft ft

MDCpar_1B DCWpar Lo llip CGp

0.5 kipft ft

0.4 klf

Lspread_B Lo llip width3 2in

spread 30deg

wspread_B Lspread_Btan(spread) 1.2in

Mcb_1B

McbLc Lc 2wspread_B

15.3 kipft ft

Mtotal_1B Mcb_1B MDCdeck_1B MDCpar_1B

15.9 kipft ft

Mrtt_p

19.2 kipft ft

Mrtt_p t Mtotal_1B 1

Pn 67.4kip

Pu

T Lc 2Hpar Lc 2Hpar 2wspread_B

6.5 kip

Pn t Pu 1

Mu_1B

Mrtt_p 1




Pu

Pn



17.4 kipft ft

Mu_1B t Mtotal_1B 1

DC - 1C: Design Section in First Span

Assumptions: Moment of collision loads is distributed over the length Lc + 30 degree spread from face of

parapet to location of overhang design section.

Axial force of collision loads is distributed over the length Lc + 2Hpar + 30 degree spread from

face of parapet to location of overhang design section.

Future wearing surface is neglected as contribution is negligible.

Mpar_G1 MDCpar_1B

0.5 kipft ft

Mpar_G2

0.137 kipft ft

(From model output)

M1 Mcb

15.6 kipft ft

M2

M1

Mpar_G2 Mpar_G1

4.7 kipft ft

bf 10.5in

Mc_M2M1

M1

1 4



bf



M1



M2

spacingint_max

14.1 kipft ft

A-56

Lspread_C wspread_C

Lo

llip



wbase



bf 4

Lspread_Ctan(spread)

4.6 in 2.7 in

Mcb_1C

Mc_M2M1Lc Lc 2wspread_C

13.6 kipft ft

Mtotal_1C Mcb_1C MDCdeck_1B MDCpar_1B

14.2 kipft ft

Mrtt_p

19.2 kipft ft

Mrtt_p t Mtotal_1C 1

Pn 67.4kip

PuC

T Lc 2Hpar Lc 2Hpar 2wspread_C

6.4 kip

Pn t PuC 1

Mu_1C

Mrtt_p 1




Pu

Pn



17.4 kipft ft

Mu_1B t Mtotal_1B 1

Compute Overhang Reinforcement Cut-off Length Requirement

Maximum crash load moment at theoretical cut-ff point:

Mc_max Mrtt

10.2 kipft ft

LMc_max

M2 M2



Mrtt M1



spacingint_max

2.1 ft

Lspread_D Lo llip wbase LMc_max 27.7in

wspread_D Lspread_Dtan(spread) 16in

Mcb_max

Mc_maxLc Lc 2wspread_D

8.3 kipft ft

extension max dtt_add12tt_add0.0625spacingint_max

cutt_off LMc_max extension

Att_add

tt_add 2 2

0.3 in2

33.2 in

mthick_tt_add 1.4 if tdeck ct t 12in 1

7.5 in

1.0 otherwise

mepoxy_tt_add

1.5

if

ct

3tt_add

stt_add 2



tt_add 6tt_add

1.5

1.2 otherwise

minc_tt_add min mthick_tt_addmepoxy_tt_add 1.7 1.5

mdec_tt_add

0.8 if stt_add t 6in 2

1

1.0 otherwise

A-57

ldb_tt_add

max


1.25inAtt_add fc

Fs kip

0.4tt_add

Fs ksi

if

tt_add d

11 in
8



ksi



2.70in Fs ksi
fc

if

tt_add =

14 in
8

ksi

ldb_tt_add 15in

3.50in Fs ksi
fc ksi

if

tt_add =

18 in
8

ldt_tt_add ldb_tt_addminc_tt_addmdec_tt_add 22.5in Cuttoffpoint LMc_max ldt_tt_add spacingint_max 13.2in extension past second interior girder

Check for Cracking in Overhang under Service Limit State: Does not govern - no live load on overhang.

25. COMPRESSION SPLICE:

See sheet S7 for drawing.

Ensure compression splice and connection can handle the compressive force in the force couple due to the negative moment over the pier.

Live load negative moment over pier:

MLLPier 541.8kipft

Factored LL moment:

MUPier 1.75MLLPier 948.1kipft

The compression splice is comprised of a splice plate on the underside of the bottom flange, and built-up angles on either side of the web, connecting to the bottom flange as well.

Calculate Bottom Flange Stress:

Composite moment of inertia:

Iz 13940.9in4

Distance to center of bottom flange from composite section centroid: Stress in bottom flange:
Calculate Bottom Flange Force: Design Stress:
Effective Flange Area:

ybf

tbf 2



Dw

ttf



tslab

yc

fbf

MUPier

ybf Iz

22.4 ksi

27.4 in

Fbf

max

fbf

2

Fy

0.75Fy

Aef bbftbf 8.5in2

37.5 ksi

Force in Flange:

Cnf FbfAef 319.1kip

Calculate Bottom Flange Stress, Ignoring Concrete:

Moment of inertia:

Izsteel 5815.1in4

Distance to center of bottom flange:

ybfsteel

tbf 2



Dw

ttf



ysteel

16.1 in

A-58

Stress in bottom flange:
Bottom Flange Force for design: Design Stress: Design Force:

fbfsteel

MUPier

ybfsteel Izsteel

31.4 ksi

Fcf

max

fbfsteel 2



Fy

0.75Fy

40.7 ksi

Cn max Fbf Fcf Aef 346.5kip

Compression Splice Plate Dimensions:

Bottom Splice Plate:

bbsp bbf 11.5in

tbsp 0.75in

Built-Up Angle Splice Plate Horizontal Leg: Built-Up Angle Splice Plate Vertical Leg:

basph 4.25in baspv 7.75in

tasph 0.75in taspv 0.75in

Total Area:

Acsp Absp Aasph Aaspv 26.6in2

Average Stress:

fcs

Proportion Load into each plate based on area:

Cn Acsp

13 ksi

Absp bbsptbsp 8.6in2 Aasph 2basphtasph 6.4in2 Aaspv 2baspvtaspv 11.6in2

Cbsp

CnAbsp Acsp

112.3kip

Casph

CnAasph Acsp

83 kip

Caspv

CnAaspv Acsp

151.3kip

Check Plates Compression Capacity:

Bottom Splice Plate:

kcps 0.75 for bolted connection

lcps 9in

rbsp Pebsp

min

bbsp

tbsp3

tbsp

bbsp3



12

12

Absp

2EsAbsp

kcpslcps 2





rbsp

2539.7 kip

0.2 in

Qbsp

1.0 if bbsp d 0.45 Es

tbsp

Fy

1.34



0.76

bbsp





Fy

if 0.45

Es d bbsp d 0.91

Es



tbsp Es

Fy tbsp

Fy

0.53Es

Fy



bbsp tbsp



2

otherwise

Pobsp QbspFyAbsp 369.2kip

0.856

A-59

Pnbsp





Pobsp





0.658 Pebsp Pobsp

if

Pebsp t 0.44 Pobsp

0.877Pebsp otherwise

Pnbsp_allow 0.9Pnbsp 312.7kip

Check

347.4kip
"NG" if Cbsp t Pnbsp_allow "OK" if Pnbsp_allow t Cbsp

"OK"

Horizontal Angle Leg:

kcps 0.75 lcps 9in

for bolted connection

rasph Peasph

min

basph

tasph3

tasph

basph3



12

12

Aasph

2EsAasph

kcpslcps 2





rasph

938.6kip

0.153in

Qasph

1.0 if basph d 0.45 Es

tasph

Fy

1

1.34



0.76

basph





Fy

if 0.45

Es d basph d 0.91

Es



tasph Es

Fy tasph

Fy

0.53Es

Fy



basph tasph



2

otherwise

Poasph QasphFyAasph 318.7kip

Vertical Angle Leg:

Pnasph





Poasph





0.658 Peasph Poasph

if

Peasph t 0.44 Poasph

276.5kip

0.877Peasph otherwise

Pnasph_allow 0.9Pnasph 248.9kip

Check2 "NG" if Casph t Pnasph_allow

kcps 0.75 for bolted connection

"OK" if Pnasph_allow t Casph

lcps 9in

raspv

min

baspv

taspv3

taspv

baspv3



12

12

Aaspv

0.153in

Peaspv

2EsAaspv

kcpslcps 2





raspv

1711.6 kip

"OK"

A-60

Qaspv

1.0 if baspv d 0.45 Es

taspv

Fy

1

1.34



0.76

baspv





Fy

if 0.45

Es d baspv d 0.91

Es



taspv Es

Fy taspv

Fy

0.53Es

Fy



baspv taspv



2

otherwise

Poaspv QaspvFyAaspv 581.2kip

Pnaspv





Poaspv





0.658 Peaspv Poaspv

if

Peaspv t 0.44 Poaspv

504.2kip

0.877Peaspv otherwise

Pnaspv_allow 0.9Pnaspv 453.8kip

Check3 "NG" if Caspv t Pnaspv_allow

"OK" if Pnaspv_allow t Caspv

"OK"

Additional Checks: Design Bolted Connections of the splice plates to the girders, checking for shear, bearing, and slip critical connections.

26. CLOSURE POUR DESIGN: See sheet S2 for drawing of closure pour. Check the closure pour according to the negative bending capacity of the section. Use the minimum reinforcing properties for design, to be conservative.

Asteel 34.3in2

Art 1.4in2

Arb 1.9in2

cgsteel tslab ysteel 24.4in

cgrt

3in 1.5 5 in 8

Overall CG: Aneg Asteel Art Arb 37.6in2

3.9 in

Moment of Inertia: Izstl 3990in4

cgrb

tslab



1in



1.5

5 8

in

6.1 in

cgneg

Asteelcgsteel Artcgrt Arbcgrb Aneg

Ineg Izstl Asteel cgsteel cgneg 2 Art cgrt cgneg 2 Arb cgrb cgneg 2 5104in4

22.8 in

Section Moduli:

Stop_neg Sbot_neg

Ineg cgneg cgrt

271.2in3

Ineg

tslab ttf Dw tbf cgneg

281.7in3

rneg

Ineg 11.7in Aneg

Concrete Properties: fc 5ksi Ec 4286.8ksi

Steel Properties:

Fy 50ksi Es 29000ksi

Lbneg 13.42ft

A-61

Negative Flexural Capacity:

Slenderness ratio for compressive flange: fneg

bbf 2tbf

7.8

Fyr 0.7Fy

Limiting ratio for compactness:

pfneg

0.38

Es Fy

9.2

Limiting ratio for noncompact Hybrid Factor:

rfneg

0.56

Es Fyr

16.1

Rh 1

35 ksi

Flange compression resistance:

Dcneg2

Dw 2

15.7 in

awc

2Dcneg2tw bbftbf

2

Rb

1.0 if 2 Dcneg2 d 5.7 Es

tw

Fy

min1.01

awc





2

Dcneg2



5.7

Es



otherwi



1200 300awc tw

Fy

Rb 1

Fnc1

RbRhFy if fneg d pfneg


1




1



Fyr RhFy





fneg rfneg

pfneg pfneg





Rb Rh Fy





otherwise

Fnc1 50ksi

Lateral Torsional Buckling Resistance:

rtneg

bbf

121




Dcneg2tw

3bbftbf



2.9 in

Lpneg

1.0rtneg

Es Fy

69.1 in

Lrneg

rtneg

Es Fyr

259.5in

Compressive Resistance:

Cb 1

Fnc2

RbRhFy if Lbneg d Lpneg


minCb1 1


Fyr RhFy





Lbneg Lpneg Lrneg Lpneg

Rb Rh Fy Rb Rh F

Fnc2 42.8ksi

Fnc min Fnc1Fnc2 42.8ksi

Tensile Flexural Resistance:

Fnt RhFy 50ksi

For Strength

A-62

Ultimate Moment Resistance:

Fnt_Serv 0.95RhFy 47.5ksi

For Service

Mn_neg min FntStop_negFncSbot_neg 1003.6kipft

MUPier 948.1kipft

from external FE analysis

Check4 Mn_neg t MUPier 1
For additional design, one may calculate the force couple at the section over the pier to find the force in the UHPC closure joint. This force can be used to design any additional reinforcement used in the joint.

A-63

Summary of changes from SHRP2:
x Adapted the AASHTO LRFD Bridge Design Specifications, 6th Edition (2012) and GDOT Standards x MathCAD Design Aides provided in Appendix of the final report
- Design loadings calucation (moment, shear, and reaction) for girders - Design loadings calucation for deck x List of variable definitions added x Enhanced the descriptions for all design steps x Expansion of detail regarding girder sizing x New cross-section drawings x Load combination explanations x 12 ft travel lanes, 6 ft shoulders and 2% slope from crown to comply with GDOT standards
A-64

File Name: Steel Girder-60 ft.xmcd
CONCRETE DECKED STEEL GIRDER DESIGN FOR ABC
The following example details the design of a steel girder bridge accompanied by precast concrete deck panels. This particular example was created in accordance with Accelerated Bridge Construction (ABC) principles. The example shown here is presented for a Georgia Department of Transportation research endeavour into ABC technology, and is intended to simplify the design procedure of ABC style bridges. This example was taken from the SHRP 2 Manual (S2-R04-RR-2), and modified by a Georgia Southern University research team working for the Georgia Department of Transportation.
Note: These calculations do not consider every aspect of the bridge design process, and should not be condsidered exhaustive.
Note: All user inputs are highlighted in yellow for easy identification.
AASHTO LRFD Bridge Design Specifications (Sixth Edition with 2012 interims) was used to formulate this example. Located throughout this example are direct references to the AASHTO LRFD Bridge Design Specifications, which are found to the right side of their affiliated calculation.
Before beginning this example, a structural modeling program was used to analyze the superstructure. Although the calculations are not shown, the outputs are used for the design moments, shears and reactions in the example. BRIDGE GEOMETRY:

Design member parameters:

Deck Width: Roadway Width: Skew Angle:

wdeck 36ft 2in wroadway 33ft Skew 0deg

Deck Thickness Haunch Thickness Haunch Width Girder Spacing

td 10.5in th 2in wh 10.5in spacingint 2ft 11in spacingext 3ft

C. to C. Piers: C. to C. Bearings Bridge Length:

Length 60ft Lspan 57ft 10in Ltotal 3Length 180 ft

Stringer

W30x90

Stringer Weight

ws1 90plf

Stringer Length

Lstr Length 6in 59.5 ft

Average spacing of adjacent beams. This value is used so that effective deck width is not overestimated.

A-65

TABLE OF CONTENTS: General: 1. Introduction 2. Design Philosophy 3. Design Criteria 4. Material Properties 5. Load Combinations Girder Design: 6. Beam Section Properties 7. Permanent Loads 8. Precast Lifting Weight 9. Live Load Distribution Factors 10. Load Results 11. Flexural Strength 12. Flexural Strength Checks 13. Flexural Service Checks 14. Shear Strength 15. Fatigue Limit States 16. Bearing Stiffeners 17. Shear Connectors Deck Design: 18. Slab Properties 19. Permanent Loads 20. Live Loads 21. Load Results 22. Flexural Strength Capacity Check 23. Longitudinal Deck Reinforcing Design 24. Design Checks 25. Deck Overhang Design Continuity Design: 26. Compression Splice 27. Closure Pour Design
A-66

List of Variable Definitions
A = plan area of ice floe (ft2); depth of temperature gradient (in.) (C3.9.2.3) (3.12.3) AEP = apparent earth pressure for anchored walls (ksf) (3.4.1) AF = annual frequency of bridge element collapse (number/yr.) (C3.14.4) AS = peak seismic ground acceleration coefficient modified by short-period site factor (3.10.4.2) = notional slope of backfill (degrees) (3.11.5.8.1) B = equivalent footing width (ft) (3.11.6.3) Be = width of excavation (ft) (3.11.5.7.2b) BM = beam (width) for barge, barge tows, and ship vessels (ft) (C3.14.5.1) Bp = width of bridge pier (ft) (3.14.5.3) BR = vehicular braking force; base rate of vessel aberrancy (3.3.2) (3.14.5.2.3) b = braking force coefficient; width of a discrete vertical wall element (ft) (C3.6.4) (3.11.5.6) bf = width of applied load or footing (ft) (3.11.6.3) C = coefficient to compute centrifugal forces; constant for terrain conditions in relation to wind approach (3.6.3) (C3.8.1.1) CD = drag coefficient (s2 lbs./ft4) (3.7.3.1) CH = hydrodynamic mass coefficient (3.14.7) CL = lateral drag coefficient (C3.7.3.1) Csm = elastic seismic response coefficient for the mth mode of vibration (3.10.4.2) c = soil cohesion (ksf) (3.11.5.4) cf = distance from back of a wall face to the front of an applied load or footing (ft) (3.11.6.3) D = depth of embedment for a permanent nongravity cantilever wall with discrete vertical wall elements (ft) (3.11.5.6) DE = minimum depth of earth cover (ft) (3.6.2.2) Do = calculated embedment depth to provide equilibrium for nongravity cantilevered with continuous vertical elements by the simplified method (ft) (3.11.5.6) D1 = effective width of applied load at any depth (ft) (3.11.6.3) d = depth of potential base failure surface below base of excavation (ft); horizontal distance from the back of a wall face to the centerline of an applied load (ft) (3.11.5.7.2b) (3.11.6.3) dc = total thickness of cohesive soil layers in the top 100 ft (3.10.3.1) ds = total thickness of cohesionless soil layers in the top 100 ft (3.10.3.1) E = Young's modulus (ksf) (C3.9.5) EB = deformation energy (kip-ft) (C3.14.11) e = eccentricity of load on footing (ft) (3.11.6.3) F1 = lateral force due to earth pressure (kip/ft) (3.11.6.3) F2 = lateral force due to traffic surcharge (kip/ft) (3.11.6.3) f = constant applied in calculating the coefficient C used to compute centrifugal forces, taken equal to 4/3 for load combinations other than fatigue and 1.0 for fatigue (3.6.3) fc = specified compressive strength of concrete for use in design (ksi) (3.5.1) g = gravitational acceleration (ft/s2) (3.6.3) H = ultimate bridge element strength (kip); final height of retaining wall (ft); total excavation depth (ft); resistance of bridge component to a horizontal force (kip) (C3.11.1) (3.11.5.7.1) (3.14.5.4) Hp = ultimate bridge pier resistance (kip) (3.14.5.4) Hs = ultimate bridge superstructure resistance (kip) (3.14.5.4) H1 = distance from ground surface to uppermost ground anchor (ft) (3.11.5.7.1) Hn+1 = distance from base of excavation to lowermost ground anchor (ft) (3.11.5.7.1) h = notional height of earth pressure diagram (ft) (3.11.5.7) heq = equivalent height of soil for vehicular load (ft) (3.11.6.4) IM = dynamic load allowance (C3.6.1.2.5) k = coefficient of lateral earth pressure; number of cohesive soil layers in the top 100 ft (3.11.6.2) (3.10.3.1) ka = coefficient of active lateral earth pressure (3.11.5.1) ko = coefficient of at rest lateral earth pressure (3.11.5.1) kp = coefficient of passive lateral earth pressure (3.11.5.1) ks = coefficient of earth pressure due to surcharge (3.11.6.1) L = perimeter of pier (ft); length of soil reinforcing elements in an MSE wall (ft); length of footing (ft);
A-67

expansion length (in.) (3.9.5) (3.11.5.8) (3.11.6.3) (3.12.2.3) = characteristic length (ft); center-to-center spacing of vertical wall elements (ft) (C3.9.5) (3.11.5.6) m = multiple presence factor; number of cohesionless soil layers in the top 100 ft (3.6.1.1.2) (3.10.3.1) N = average Standard Penetration Test (SPT) blow count (blows/ft) (ASTM D1586) for the upper 100 ft of the soil profile (3.10.3.1)
Nch = average Standard Penetration Test (SPT) blow count (blows/ft) (ASTM D1586) for cohesive soil layers in the upper 100 ft of the soil profile and us for cohesive soil layers (PI > 20) in the top 100 ft ( us method) (3.10.3.1) Nchi = blowcount for a cohesionless soil layer (not to exceed 100 blows/ft in the above expression) (3.10.3.1) Ni = Standard Penetration Test blow count of a layer (not to exceed 100 blows/ft in the above expression). Note that when using Method B, N values are for cohesionless soils and cohesive soil and rock layers within the upper 100 ft Where refusal is met for a rock layer, Nishould be taken as 100 blows/ft (3.10.3.1) Ns = stability number (3.11.5.6) OCR = overconsolidation ratio (3.11.5.2) P = maximum vertical force for single ice wedge (kip); load resulting from vessel impact (kip); concentrated wheel load (kip); live load intensity; point load (kip) (C3.9.5) (3.14.5.4) (C3.6.1.2.5) (C3.11.6.2) (3.11.6.1) Pa = force resultant per unit width of wall (kip/ft) (3.11.5.8.1) PC = probability of bridge collapse (3.14.5) PD = design wind pressure (ksf) (3.8.1.2.1) PGA = peak seismic ground acceleration coefficient on rock (Site Class B) (3.10.2.1) (3.10.4.2) PH = lateral force due to superstructure or other concentrated lateral loads (kip/ft) (3.11.6.3) Ph = horizontal component of resultant earth pressure on wall (kip/ft) (3.11.5.5) PI = plasticity index (ASTM D4318) (3.10.3.1) Pp = passive earth pressure (kip/ft) (3.11.5.4) Pv = vertical component of resultant earth pressure on wall (kip/ft); load per linear foot of strip footing (kip/ft) (3.11.5.5) (3.11.6.3) Pv = load on isolated rectangular footing or point load (kip) (3.11.6.3) p = effective ice crushing strength (ksf); stream pressure (ksf); basic earth pressure (psf); fraction of truck traffic in a single lane; load intensity (ksf) (3.9.2.2) (3.7.3.1) (3.11.5.1) (3.6.1.4.2) (3.11.6.1) pa = apparent earth pressure (ksf); maximum ordinate of pressure diagram (ksf) (3.11.5.3) (3.11.5.7.1) pp = passive earth pressure (ksf) (3.11.5.4) Q = total factored load; load intensity for infinitely long line loading (kip/ft) (3.4.1) (3.11.6.2) Qi = force effects (3.4.1) q = surcharge pressure (ksf) (3.11.6.3) qs = uniform surcharge pressure (ksf) (3.11.6.1) R = radius of curvature (ft); radius of circular pier (ft); seismic response modification factor; reduction factor of lateral passive earth pressure; radial distance from point of load application to a point on the wall (ft); reaction force to be resisted by subgrade below base of excavation (kip/ft) (3.6.3) (3.9.5) (3.10.7.1) (3.11.5.4) (3.11.6.1) (3.11.5.7.1) Sm = shear strength of rock mass (ksf) (3.11.5.6) Su = undrained shear strength of cohesive soil (ksf) (3.11.5.6) Sub = undrained strength of soil below excavation base (ksf) (3.11.5.7.2b) Sv = vertical spacing of reinforcements (ft) (3.11.5.8.1) us = average undrained shear strength in ksf (ASTM D2166 or ASTM D2850) for the upper 100 ft of the soil profile (3.10.3.1) sui = undrained shear strength for a cohesive soil layer (not to exceed 5.0 ksf in the above expression) (3.10.3.1) S1 = horizontal response spectral acceleration coefficient at 1.0-s period on rock (Site Class B) (3.10.2.1) (3.10.4.2) T = mean daily air temperature (F) (C3.9.2.2) TF = period of fundamental mode of vibration of bridge (s) (3.10.2.2) Thi = horizontal load in anchor i (kip/ft) (3.11.5.7.1) Tm = period of vibration for mth mode (s) (3.10.4.2) Tmax = applied load to reinforcement in a mechanically stabilized earth wall (kip/ft) (3.11.5.8.2) TMaxDesign= maximum design temperature used for thermal movement effects (F) (3.12.2.1) (3.12.2.2) (3.12.2.3) TMinDesign = minimum design temperature used for thermal movement effects (F) (3.12.2.1) (3.12.2.2) (3.12.2.3) TS = corner period at which acceleration response spectrum changes from being independent of period to being inversely proportional to period (s) (3.10.4.2) T0 = reference period used to define shape of acceleration response spectrum (s) (3.10.4.2)
A-68

t = thickness of ice (ft); thickness of deck (in.) (3.9.2.2) (3.12.3) V = design velocity of water (ft/s); design impact speed of vessel (ft/s) (3.7.3.1) (3.14.6) VB = base wind velocity taken as 100 mph (3.8.1.1) VDZ = design wind velocity at design Elevation Z (mph) (3.8.1.1) VMIN = minimum design impact velocity taken not less than the yearly mean current velocity for the bridge location (ft/s) (3.14.6) V0 = friction velocity, a meteorological wind characteristic for various upwind surface characteristics (mph) (3.8.1.1) V30 = wind speed at 30.0 ft above low ground or water level (mph) (3.8.1.1) v = highway design speed (ft/s) (3.6.3) s v = average shear wave velocity for the upper 100 ft of the soil profile (3.10.3.1) W = displacement weight of vessel (tonne) (C3.14.5.1) w = width of clear roadway (ft); width of clear pedestrian and/or bicycle bridge (ft); width of pier at level of ice action (ft); specific weight of water (kcf); moisture content (ASTM D2216) (3.6.1.1.1) (3.6.1.6) (3.9.2.2) (C3.7.3.1) (3.10.3.1) X = horizontal distance from back of wall to point of load application (ft); distance to bridge element from the centerline of vessel transit path (ft) (3.11.6.2) (3.14.6) X1 = distance from the back of the wall to the start of the line load (ft) (3.11.6.2) X2 = length of the line load (ft) (3.11.6.2) Z = structure height above low ground or water level > 30.0 ft (ft); depth below surface of soil (ft); depth from the ground surface to a point on the wall under consideration (ft); vertical distance from point of load application to the elevation of a point on the wall under consideration (ft) (3.8.1.1) (3.11.6.3) (3.11.6.2) Z0 = friction length of upstream fetch, a meteorological wind characteristic (ft) (3.8.1.1) Z2 = depth where effective width intersects back of wall face (ft) (3.11.6.3) z = depth below surface of backfill (ft) (3.11.5.1) = constant for terrain conditions in relation to wind approach; coefficient for local ice condition; inclination of pier nose with respect to a vertical axis (degrees); inclination of back of wall with respect to a vertical axis (degrees); angle between foundation wall and a line connecting the point on the wall under consideration and a point on the bottom corner of the footing nearest to the wall (rad); coefficient of thermal expansion (in./in./F) (C3.8.1.1) (C3.9.2.2) (3.9.2.2) (C3.11.5.3) (3.11.6.2) (3.12.2.3) = safety index; nose angle in a horizontal plane used to calculate transverse ice forces (degrees); slope of backfill surface behind retaining wall; {+ for slope up from wall; for slope down from wall} (degrees) (C3.4.1) (3.9.2.4.1) (3.11.5.3)
= slope of ground surface in front of wall {+ for slope up from wall; for slope down from wall} (degrees) (3.11.5.6) = load factors; unit weight of materials (kcf); unit weight of water (kcf); unit weight of soil (kcf) (C3.4.1) (3.5.1) (C3.9.5) (3.11.5.1) s = unit weight of soil (kcf) (3.11.5.1) s = effective soil unit weight (kcf) (3.11.5.6) EQ = load factor for live load applied simultaneously with seismic loads (3.4.1) eq = equivalent-fluid unit weight of soil (kcf) (3.11.5.5) i = load factor (3.4.1) p = load factor for permanent loading (3.4.1) SE = load factor for settlement (3.4.1) TG = load factor for temperature gradient (3.4.1) = movement of top of wall required to reach minimum active or maximum passive pressure by tilting or lateral translation (ft) (C3.11.1) (3.11.5.5) p = constant horizontal earth pressure due to uniform surcharge (ksf) (3.11.6.1) ph = constant horizontal pressure distribution on wall resulting from various types of surcharge loading (ksf) (3.11.6.2) T = design thermal movement range (in.) (3.12.2.3) iH = horizontal stress due to surcharge load (ksf) (3.11.6.3) iv = vertical stress due to surcharge load (ksf) (3.11.6.3) = angle of truncated ice wedge (degrees); friction angle between fill and wall (degrees); angle between foundation wall and a line connecting the point on the wall under consideration and a point on the bottom corner of the footing furthest from the wall (rad) (C3.9.5) (3.11.5.3) (3.11.6.2) i = load modifier specified in Article 1.3.2; wall face batter (3.4.1) (3.11.5.9)
A-69

= angle of back of wall to the horizontal (degrees); angle of channel turn or bend (degrees); angle between direction of stream flow and the longitudinal axis of pier (degrees) (3.11.5.3) (3.14.5.2.3) (3.7.3.2) f = friction angle between ice floe and pier (degrees) (3.9.2.4.1) i = standard deviation of normal distribution (3.14.5.3) iT = tensile strength of ice (ksf) (C3.9.5) = Poisson's Ratio (dim.) (3.11.6.2) = resistance factors (C3.4.1) f = angle of internal friction (degrees) (3.11.5.4)
f = effective angle of internal friction (degrees) (3.11.5.2) r = internal friction angle of reinforced fill (degrees) (3.11.6.3) s = angle of internal friction of retained soil (degrees) (3.11.5.6)

Permanent Loads CR = force effects due to creep DD = downdrag force DC = dead load of structural components and nonstructural attachments DW = dead load of wearing surfaces and utilities EH = horizontal earth pressure load EL = miscellaneous locked-in force effects resulting from the construction process, including jacking apart of cantilevers in segmental construction ES = earth surcharge load EV = vertical pressure from dead load of earth fill

Transient Loads
EQ = earthquake load FR = friction load IC = ice load IM = vehicular dynamic load allowance LL = vehicular live load LS = live load surcharge PL = pedestrian live load SE = force effect due to settlement TG = force effect due to temperature gradient TU = force effect due to uniform temperature WA = water load and stream pressure WL = wind on live load WS = wind load on structure

1. INTRODUCTION
AASHTO LRFD principles were used in the design of this superstructure. The example is designed for a bridge with three even spans, and has no skew. The bridge has two 12-foot wide lanes and two 6-foot wide shoulders, for a total roadway width of 36' from curb to curb. The bridge deck is precast reinforced concrete with overhangs at the outermost girders. The longitudinal girders are placed as simply supported modules, and made continuous with connection plates and cast-in-place deck joints. The design of the continuity at the deck joint is addressed in final sections of this example.

The cross-section consists of six modules. The interior modules are identical and consist of two steel girders and a 6'-0" precast composite deck slab. Exterior modules include two steel girders and a 6'-1" precast composite deck slab, with F-shape barriers. Grade 50 steel is used throughout, and the deck concrete has a compressive strength of 5,000 psi.
A-70

The closure pour joints between the modules use Ultra High Performance Concrete with a strength of 21,000 psi.
Steel girder design steps, including constructability checks, fatigue design for infinite fatigue lift (unless otherwise noted), and bearing stiffener design comprise the majority of the example. Diaphragm and deck design procedures are present, but not detailed.

Tips for reading this Design Example:

This calculation was prepared with Mathcad version 14. Mathcad was used in this instance to provide a clear representation of formulas, and their execution. Design software other than Mathcad is recommended for a speedier and more accurate design.

Mathcad is not a design software. Mathcad executes user mathematical and simple logic commands.

Example 1: User inputs are noted with dark shaded boxes. Shading of boxes allows the user to easily find the location of a desired variable. Given that equations are written in mathcad in the same fashion as they are on paper, except that they are interactive, shading input cells allows the user to quicly locate inputs amongst other data on screen. Units are user inputs.

Height of Structure:

Hstructure 25ft

Example 2: Equations are typed directly into the workspace. Mathcad then reads the operators and executes the calculations.

Panels are 2.5'

Npanels

Hstructure 2.5ft

Npanels 10

Example 3: If Statements are an important operator that allow for the user to dictate a future value with given parameters. They are marked by a solid bar and operate with the use of program specific logic commands.

Operator offers discount per volume of panels

Discount

.75 if Npanels t 6 .55 if Npanels t 10

Discount 0.6

1 otherwise
Example 4: True or False Verification Statements are an important operator that allow for the user to verify a system criteria that has been manually input. They are marked by lighter shading to make a distinction between the user inputs. True or false statements check a single or pairs of variables and return a Zero or One.

Owner to proceed if discounts on retail below 60%

Discount d .55 1

2. DESIGN PHILOSOPHY

The superstructure of the bridge in this example consists of modules, which are two rolled steel girders supporting a bridge deck panel along their length. The girders are assumed to be simply supported under the weight of the deck panels. In each module, one girder is assumed to support half the weight of its respective deck panel.

The barrier wall is added to exterior modules once the deck and girders are joined. When working with the barrier dead load, the weight is assumed to be evenly distributed between the two modules. Under the additional barrier dead load, the girders are again assumed to be simply supported.

Concerning transportation of modules, it is assumed that the deck has reached 28-day concrete strength, and the deck is fully composite with the girders. The self-weight of the module during lifting and placement is assumed as evenly distributed to four pick points (two per girder).

The modules are placed such that there is a bearing on each end and are again simply supported. The continuous span

A-71

configuration, which includes two bearings per pier on either side of the UHPC joints, is analyzed for positive and negative bending and shear (using simple or refined methods). The negative bending moment above the pier is used to find the force couple for continuity design, between the compression plates at the bottom of the girders and the closure joint in the deck.
The deck design utilizes the equivalent strip method.

3. DESIGN CRITERIA
The first step for any bridge design is to establish the design criteria. The following is a summary of the primary design criteria for this design example:

Governing Specifications: AASTHO LRFD Bridge Design Specifications (6th Edition with 2012 interims)

Design Methodology:

Load and Resistance Factor Design (LRFD)

Live Load Requirements: HL-93

S S3.6

Section Constraints:

Wmod.max 200kip Upper limit on the weight of the modules, based on common lifting and transport capabilities without significantly increasing time and/or cost due to unconventional equipment or permits

4. MATERIAL PROPERTIES Structural Steel Yield Strength: Structural Steel Tensile Strength: Concrete 28-day Compressive Strength: Reinforcement Strength: Steel Density: Concrete Density: Modulus of Elasticity - Steel: Modulus of Elasticity - Concrete:
Modular Ratio:
Future Wearing Surface Density: Future Wearing Surface Thickness:

Fy 50ksi

Fu 65ksi

fc 5ksi

fc_uhpc 21ksi

Fs 60ksi

ws 490pcf

wc 150pcf

Es 29000ksi

Ec

33000

wc



1.5

1000pcf

fcksi

n

Es ceil

7

Ec

4286.8 ksi

Wfws 140pcf tfws 2.5in

(Assumed)

STable 6.4.1-1 STable 6.4.1-1 S5.4.2.1 S5.4.3 & S6.10.3.7 STable 3.5.1-1 STable 3.5.1-1
STable 3.5.1-1

5. LOAD COMBINATIONS

A-72

The following load combinations will be used in this design example, in accordance with Table 3.4.1-1.

Strength I--Basic load combination relating to the normal vehicular use of the bridge without wind.

Strength III--Load combination relating to the bridge exposed to wind velocity exceeding 55 mph.

Strength V--Load combination relating to normal vehicular use of the bridge with wind of 55 mph velocity.

Service I--Load combination relating to the normal operational use of the bridge with a 55 mph wind and all loads taken at their nominal values. Also related to deflection control in buried metal structures, tunnel liner plate, and thermoplastic pipe, to control crack width in reinforced concrete structures, and for transverse analysis relating to tension in concrete segmental girders. This load combination should also be used for the investigation of slope stability.

Service II--Load combination intended to control yielding of steel structures and slip of slip-critical connections due to vehicular live load.
Fatigue I--Fatigue and fracture load combination related to infinite load-induced fatigue life.

Strength I = 1.25DC + 1.5DW + 1.75(LL+IM), where IM = 33% Strength III = 1.25DC + 1.5DW + 1.40WS Strength V = 1.25DC + 1.5DW + 1.35(LL+IM) + 0.40WS + 1.0WL, where IM = 33% Service I = 1.0DC + 1.0DW + 1.0(LL+IM) + 0.3WS + 1.0WL, where IM = 33% Service II = 1.0DC + 1.0DW + 1.3(LL+IM), where IM = 33% Fatigue I = 1.5(LL+IM), where IM = 15%

6. BEAM SECTION
Determining the proper girder depth and dimensions is a vital part of any bridge design process. The size of the girder is a major factor in the cost of the bridge. From Table 2.5.2.6.3-1, the suggested minimum overall depth of the composite I-section in a continuous span is equal to 0.032L.
Thus we have, (.032*60ft) = 1.92' = 23.04" (this is a minimum and may be altered to satisfy criteria)
The following girder dimensions were taken from the AISC Steel Construction Manual (14th Edition).

Determine Beam Section Properties:

Girder

W30x90

btfx ttf

A-73

Top Flange Bottom Flange Web Girder Depth

btf 10.4in bbf 10.4in Dw 31.4in dgird 29.5in

ttf 0.61in tbf 0.61in tw 0.47in

Dw x tw bbfx tbf

Check Flange Proportion Requeirements Met:

btf d 12.0 1 2ttf

btf

t

Dw 6

1

ttf t 1.1tw 1 tbf 3 bbf

0.1 d 12 d 10 1 ttf 3 btf

12

bbf d 12.0 1 2tbf

bbf

t

Dw 6

1

tbf t 1.1tw 1

tbf bbf

12 t 0.3 1 ttf btf

12

Properties for use when analyzing under beam self weight (steel only):

S 6.10.2.2

Atf btfttf

Abf bbftbf

Asteel Abf Atf Aw

Aw Dwtw Asteel 27.4in2

ysteel

Atf



ttf 2



Abf





tbf 2



Dw

ttf



Aw



Dw 2



ttf

Asteel

ysteel 16.3in

Total steel area. Steel centroid from top.

Calculate Iz:

Moment of inertia about Z axis.

Izsteel

twDw3 12



btf ttf 3 12



bbftbf3 12



Aw



Dw 2



ttf



ysteel2

Atf





ysteel



ttf 2 2

Abf





Dw



tbf 2



ttf



y steel 2

Calculate Iy:

Iysteel

Dwtw3 ttfbtf3 tbfbbf3 12

Moment of inertia about Y axis.

Calculate Ix:

Ixsteel

1 3





btf



ttf

3



bbftbf3



Dwtw3

Izsteel 4463.118in4

Iysteel

114.633 in4

Moment of inertia about X axis.

Ixsteel 2.7in4

Asteel 27.4in2

A-74

Composite Section Properties (Uncracked Section - used for barrier dead load and live load positive bending): Determine composite slab and reinforcing properties

Slab thickness assumes some sacrificial thickness; use:
Dt tslab ttf Dw tbf 40.6in

tslab 8in Total section depth

beff spacingint beff 35in

Effective width.

S 4.6.2.6.1 LRFD

btr

beff n

Transformed slab width as steel.

Izslab

btr

tslab3 12

Transformed slab moment of inertia about z axis as steel.

Aslab btrtslab

Transformed slab area as steel.

Slab reinforcement: (Use #5 @ 8" top, and #6 @ 8" bottom; additional bar for continuous segments of #6 @ 12")

Typical Cross Section

Art

0.465

in2 ft



beff

1.4 in2

Cross Section Over Support

Arb

0.66

in2 ft



beff

1.9 in2

Artadd

0.44

in2 ft



beff

1.3 in2

A-75

Ar Art Arb 3.3in2

crt

2.5in



0.625in





5 16

in

cr

Artcrt Arbcrb Ar

4.9 in

3.4 in

Arneg Ar Artadd 4.6in2

crb

tslab



1.75in





6 16



in

5.9 in

ref from top of slab

crneg

Artcrt Arbcrb Artaddcrt
Arneg

4.5 in

Find composite section centroid:

Ax

Asteel

Ar(n n

1)

Aslab

yslab

tslab 2

yst

Atf





ttf 2



tslab



Abf





tbf 2



Dw

ttf



tslab



Aw



Dw 2



ttf



tslab

Asteel

yc

ystAsteel

crAr(n 1) n

Aslabyslab

Ax

yc 12in

Calculate Transformed Iz for composite section:

Iz

Izsteel



Asteel

yst



yc

2

Izslab



Aslab

yslab

yc

2

Ar(n n

1)

cr

yc

2

Calculate Transformed Iy for composite section:

ttr

tslab n

Iyslab

ttr b eff 3 12

Transformed slab thickness. Transformed moment of inertia about y axis of slab.

Iy Iysteel Iyslab

Transformed moment of inertia about the y axis (ignoring reinforcement).

Centroid of steel from top of slab.
Centroid of transformed composite section from top of slab.
Transformed moment of inertia about the z axis.

Calculate Transformed Ix for composite section:

Ix

1 3





btf



ttf

3



bbftbf3



Dwtw3



btrtslab3

Transformed moment of inertia about the x axis.

Results: Ax 70.3in2 Iy 4198in4

Iz 11538.5in4 Ix 856in4

Composite Section Properties (Uncracked Section - used for live load negative bending):

Find composite section area and centroid:

Axneg

Asteel

Arneg(n n

1)



Aslab

ycneg

ysteelAsteel

crnegArneg(n n

1)



Aslabyslab

Axneg

ycneg 8.8in

Centroid of transformed composite section from top of slab.

A-76

Calculate Transformed Izneg for composite negative moment section:

Izneg

Izsteel

Asteel

ysteel

ycneg

2

Izslab

Aslab

yslab

ycneg

2

Arneg(n n

1)

crneg

ycneg

2

Transformed moment of inertia about the z

axis.

Izneg 7219.4in4

Composite Section Properties (Cracked Section - used for live load negative bending):

Find cracked section area and centroid:

Acr ycr

Asteel Arneg 32in2
Asteelysteel Arnegcrneg
Acr

14.6 in

ycrb

Find cracked section moments of inertia and section moduli:

Izcr Izsteel Asteel ysteel ycr 2 Ar cr ycr 2

Izcr

tslab ttf Dw tbf ycr 4853.6 in4

Iycr Iysteel

Ixcr

1 3





btf



ttf

3



b bf ttf 3



Dwtw3

dtopcr ycr crt

Iycr 114.6in4 Ixcr 2.7in4 dtopcr 11.2in

26 in

dbotcr Stopcr

tslab ttf Dw tbf ycr Izcr dtopcr

Sbotcr

Izcr dbotcr

dbotcr Stopcr

26 in 434 in3

Sbotcr 186.7in3

7. PERMANENT LOADS

Phase 1: Steel girders are simply supported, and support their self-weight plus the weight of the slab. Steel girders in each module for this example are separated by three diaphragms - one at each bearing location, and one at midspan. Other module span configurations may require an increase or decrease in the number of diaphragms.

Wdeck_int wcspacinginttd

Wdeck_int 382.8plf

Wdeck_ext wcspacingexttd

Wdeck_ext 393.8plf

Whaunch wcwhth

Whaunch 21.9plf

Wstringer ws1

Wstringer 90plf

Diaphragms: Diaphragm Weight

MC18x42.7 ws2 42.7plf

Thickness Conn. Plate Width Conn. Plate

tconn

5 in
8

wconn 5in

Diaphragm Length

Wdiaphragm

ws2

Ldiaph 2

Ldiaph 4ft 2.5in

Height Conn. Plate

hconn 28.5in

Wdiaphragm 89.8lbf

A-77

Wconn 2wstconnwconnhconn
WDCpoint Wdiaphragm Wconn 1.05
Equivalent distributed load from DC point loads:

Wconn 50.5lbf

WDCpoint 147.4lbf

wDCpt_equiv

3WDCpoint Lstr

7.4 plf

Interior Uniform Dead Load, Phase 1: Exterior Uniform Dead Load, Phase 1:

WDCuniform1_int Wdeck_int Whaunch Wstringer wDCpt_equiv WDCuniform1_ext Wdeck_ext Whaunch Wstringer wDCpt_equiv

502.1plf 513.1plf

Moments due to Phase 1 DL: Shear due to Phase 1 DL:

MDC1_int(x)

WDCuniform1_intx 2

Lstr



x

VDC1_int(x)

WDCuniform1_int



Lstr 2



x

MDC1_ext(x)

WDCuniform1_extx 2

Lstr



x

VDC1_ext(x)

WDCuniform1_ext



Lstr 2



x

Phase 2: Steel girders are simply supported and composite with the deck slab, and support their self-weight plus the weight of the slab in addition to barriers on exterior modules. Barriers are assumed to be evenly distributed between the two exterior module girders.

Barrier Area

Abarrier 2.89ft2

Barrier Weight

Wbarrier

wcAbarrier 2

Wbarrier 216.8plf

Interior Dead Load, Phase 2:

WDCuniform_int WDCuniform1_int 502.1plf

Exterior Dead Load, Phase 2: WDCuniform_ext WDCuniform1_ext Wbarrier 729.8plf

Moments due to Phase 2 DL: Shear due to Phase 2 DL:

MDC2_int(x)

WDCuniform_intx 2

Lstr



x

VDC2_int(x)

WDCuniform_int



Lstr 2



x

MDC2_ext(x)

WDCuniform_extx 2

Lstr



x

VDC2_ext(x)

WDCuniform_ext



Lstr 2



x

Phase 3: Girders are composite and have been made continuous. Utilities and future wearing surface are applied.

Unit Weight Overlay

wws 30psf

Wws_int wwsspacingint
Wws_ext wws spacingext 1ft 7in

Wws_int 87.5plf Wws_ext 42.5plf

Unit Weight Utilities

Wu 15plf

WDWuniform_int Wws_int Wu WDWuniform_ext Wws_ext Wu Moments due to DW:
Shears due to DW:

WDWuniform_int 102.5plf

WDWuniform_ext 57.5plf

MDW_int(x)

WDWuniform_intx 2

Lstr



x

MDW_ext(x)

WDWuniform_extx 2

Lstr



x

VDW_int(x)

WDWuniform_int





Lstr 2



x

VDW_ext(x)

WDWuniform_ext



Lstr 2



x

A-78

8. PRECAST LIFTING WEIGHTS AND FORCES

This section addresses the construction loads for lifting the module into place. The module is lifted from four points, at some distance, Dlift from each end of each girder.

Distance from end of lifting point:

Dlift 8.75ft

Assume weight uniformly distributed along girder, with 30% Dynamic Dead Load Allowance:

Dynamic Dead Load Allowance:

DLIM 30%

Interior Module: Total Interior Module Weight: Vertical force at lifting point: Equivalent distributed load:
Min (Neg.) Moment during lifting:
Max (Pos.) Moment during lifting:

Wint LstrWDCuniform_int 3WDCpoint 2(1 DLIM) 78.8kip

Flift_int

Wint 4

19.7 kip

wint_IM

Wint 2Lstr

662.4plf

Mlift_neg_max_int

wint_IM



Dlift2
2

Mlift_neg_max_int 25.4kipft

Mlift_pos_max_int

0

if

wint_IM

Lstr 8

2Dlift

2



Mlift_neg_max_int



0

wint_IM

Lstr 8

2Dlift

2



Mlift_neg_max_int

Mlift_pos_max_int 120.7kipft

Exterior Module: Total Exterior Module Weight: Vertical force at lifting point: Equivalent distributed load:
Min (Neg.) Moment during lifting:

Wext LstrWDCuniform_ext 3WDCpoint WbarrierLstr 2(1 DLIM) 147.6kip

Flift_ext

Wext 4

36.9 kip

wext_IM

Wext 2Lstr

Mlift_neg_max_ext

1240.2 plf

wext_IM



Dlift2 2

Mlift_neg_max_ext 47.5kipft

A-79

Max (Pos.) Moment during lifting: Mlift_pos_max_ext

0

if

wext_IM

Lstr 8

2Dlift

2



Mlift_neg_max_ext



0

wext_IM

Lstr 8



2Dlift

2



Mlift_neg_max_ext

Max Shear during lifting:

Mlift_pos_max_ext 226kipft
Vlift max wext_IMDlift Flift_ext wext_IMDlift

26 kip

9. LIVE LOAD DISTRIBUTION FACTORS

These factors represent the distribution of live load from the deck to the girders in accordance with AASHTO Section 4, and assumes the deck is fully continuous across the joints.
Girder Section Modulus: Izsteel 4463.1in4

Girder Area:
Girder Depth:
Distance between centroid of deck and centroid of beam: Modular Ratio:

Asteel 27.4in2 dgird 29.5in

eg

td 2



th

dgird 2

n7

22 in

Multiple Presence Factors:

MP1 1.2

MP2 1.0

S3.6.1.1.2-1

Interior Stringers for Moment:
One Lane Loaded: Kg nIzsteel Asteeleg2

124228.9 in4

S4.6.2.2.1-1

Two Lanes Loaded: Governing Factor:

gint_1m

0.06





spacingint 14ft



0.4



spacingint



0.3



Lspan

Kg



0.1

Lspantd3



0.241

gint_2m

0.075





spacingint 9.5ft



0.6



spacingint



0.2



Lspan

Kg 0.1

Lspantd3



0.3

gint_m max gint_1mgint_2m 0.3

Interior Stringers for Shear: One Lane Loaded: gint_1v
Two Lanes Loaded: gint_2v

0.36 spacingint 0.477



25ft

0.2

spacingint





spacingint



2



12ft

35ft

Governing Factor: gint_v max gint_1v gint_2v 0.477
Exterior Stringers for Moment:

0.436

A-80

One Lane Loaded: Use Lever Rule. Wheel is 2' from barrier; barrier is 2" beyond exterior stringer. de 2in

Lspa 4.5ft r Lspa de 2ft 2.7ft

Two Lanes Loaded:

gext_1m

MP1

0.5r Lspa

e2m

0.77 de 9.1ft

0.356 0.7883

Governing Factor:

gext_2m e2mgint_2m 0.236
gext_m max gext_1mgext_2m

0.356

Exterior Stringers for Shear: One Lane Loaded: Use Lever Rule. gext_1v gext_1m

0.356

Two Lanes Loaded:

e2v

0.6 de 10ft

0.62

gext_2v e2vgint_2v 0.269

Governing Factor: gext_v max gext_1vgext_2v 0.356

FACTOR TO USE FOR SHEAR: gv max gint_v gext_v 0.477

FACTOR TO USE FOR MOMENT: gm max gint_mgext_m 0.356

10. LOAD RESULTS

Case 1: Dead Load on Steel Only (calculated in Section 7). Negative moments are zero and are not considered. Because the girder is simply supported, the maximum moment is at x = Lstr/2 and the maximum shear is at x = 0.

Interior Girder

MDC1int

MDC1_int



Lstr 2



222.2kipft

MDW1int 0kipft MLL1int 0kipft

Exterior Girder

VDC1int VDC1_int(0) 14.9kip

MDC1ext

MDC1_ext

Lstr 2



227kipft

VDW1int 0kip MDW1ext 0kipft

VLL1int 0kip MLL1ext 0kipft

Load Cases:

VDC1ext VDC1_ext(0) 15.3kip

VDW1ext 0kip

VLL1ext 0kipft

M1_STR_I max 1.25MDC1int 1.5MDW1int 1.75MLL1int1.25MDC1ext 1.5MDW1ext 1.75MLL1ext 283.8kipf V1_STR_I max 1.25VDC1int 1.5VDW1int 1.75VLL1int1.25VDC1ext 1.5VDW1ext 1.75VLL1ext 19.1kip

Case 2: Dead Load on Composite Section (calculated in Section 7). Negative moments are zero and are not considered. Again, the maximum moment occur at x = Lstr/2 and the maximum shear is at x = 0.

Interior Girder

MDC2int

MDC2_int



Lstr 2



222.2kipft

MDW2int 0kipft

MLL2int 0kipft

VDC2int VDC2_int(0) 14.9kip

VDW2int 0kip

VLL2int 0kip

Exterior Girder

MDC2ext

MDC2_ext

Lstr 2



323kipft

MDW2ext 0kipft

MLL2ext 0kipft

VDC2ext VDC2_ext(0) 21.7kip

VDW2ext 0kip

VLL2ext 0kip

Load Cases:
M2_STR_I max 1.25MDC2int 1.5MDW2int 1.75MLL2int1.25MDC2ext 1.5MDW2ext 1.75MLL2ext 403.7kipf

A-81

V2_STR_I max 1.25VDC2int 1.5VDW2int 1.75VLL2int1.25VDC2ext 1.5VDW2ext 1.75VLL2ext 27.1kip

Case 3: Composite girders are lifted into place from lifting points located distance Dlift from the girder edges. Maximum moments and shears were calculated in Section 8.

Interior Girder MDC3int Mlift_pos_max_int 120.7kipft

MDW3int 0kipft

MLL3int 0kipft

MDC3int_neg Mlift_neg_max_int 25.4kipft MDW3int_neg 0kipft MLL3int_neg 0kipft

VDC3int Vlift 26kip

VDW3int 0kip

VLL3int 0kip

Exterior Girder MDC3ext Mlift_pos_max_ext 226kipft

MDW3ext 0kipft

MLL3ext 0kipft

MDC3ext_neg Mlift_neg_max_ext 47.5kipft MDW3ext_neg 0kipft MLL3ext_neg 0kipft

VDC3ext Vlift 26kip

VDW3ext 0kip

VLL3ext 0kip

Load Cases:
M3_STR_I max 1.5MDC3int 1.5MDW3int1.5MDC3ext 1.5MDW3ext 339kipft
M3_STR_I_neg max 1.5MDC3int_neg 1.5MDW3int_neg 1.5MDC3ext_neg 1.5MDW3ext_neg
V3_STR_I max 1.5VDC3int 1.5VDW3int1.5VDC3ext 1.5VDW3ext 39.1kip

71.2kipft

Case 4: Composite girders made continuous. Utilities and future wearing surface are applied, and live load. Maximum

moment and shear results are from a finite element analysis not included in this design example. The live load value

includes the lane fraction calculated in Section 9, and impact.

Governing Loads: MDC4 210.2kipft

MDW4 29.5kipft

MLL4 350.16kipft

MWS4 0kipft

MW4 0kipft

MDC4neg 262.7kipft MDW4neg 36.9kipft MLL4neg 310.79kipft

MWS4neg 0kipft

MWL4neg 0kipft

VDC 26.3kip

VDW 3.7kip

VLL 100.6kip

Vu 1.25VDC 1.5VDW 1.75VLLgv 122.3kip

Load Cases: M4_STR_I 1.25MDC4 1.5MDW4 1.75MLL4 919.8kipft
M4_STR_I_neg 1.25MDC4neg 1.5MDW4neg 1.75MLL4neg 927.6kipft

M4_STR_III 1.25MDC4 1.5MDW4 1.4MWS4 307kipft M4_STR_III_neg 1.25MDC4neg 1.5MDW4neg 1.4MWS4 383.7kipft

M4_STR_V 1.25MDC4 1.5MDW4 1.35MLL4 0.4MWS4 1.0MW4 779.7kipft M4_STR_V_neg 1.25MDC4neg 1.5MDW4neg 1.35MLL4neg 0.4MWS4neg 1.0MWL4neg 803.3kipft

M4_SRV_I 1.0MDC4 1.0MDW4 1.0MLL4 0.3MWS4 1.0MW4 589.9kipft M4_SRV_I_neg 1.0MDC4neg 1.0MDW4neg 1.0MLL4neg 0.3MWS4neg 1.0MWL4neg M4_SRV_II 1.0MDC4 1.0MDW4 1.3MLL4 694.9kipft M4_SRV_II_neg 1.0MDC4neg 1.0MDW4neg 1.3MLL4neg 703.6kipft

610.4kipft

A-82

11. FLEXURAL STRENGTH
The flexural resistance shall be determined as specified in LRFD Design Article 6.10.6.2. Determine Stringer Plastic Moment Capacity First.

LFRD Appendix D6 Plastic Moment

Find location of PNA:

Forces:

Prt ArtFs 81.4kip Prb ArbFs 115.5kip

Ps 0.85fcbefftslab 1190kip Pc Fybtfttf 317.2kip

Pw FyDwtw 737.9kip Pt Fybbftbf 317.2kip

A-83

PNApos

"case 1" if Pt Pw t Pc Ps Prt Prb

otherwise
"case 2" if Pt Pw Pc t Ps Prt Prb

otherwise

"case 3"

if Pt Pw Pc


t



crb tslab



Ps



Prt



Prb


otherwise

"case 4"

if Pt Pw Pc Prb


t



crb tslab



Ps



Prt


otherwise

"case 5"

if Pt Pw Pc Prb


t



crt tslab



Ps



Prt


otherwise

"case 6"

if

Pt Pw Pc Prb Prt

t



crt tslab

Ps


"case 7"

if

Pt Pw Pc Prb Prt

d



crt tslab

Ps


otherwise

PNAneg

PNApos "case 3"
"case 1" if Pc Pw t Pt Prt Prb "case 2" if Pt Pw Pc t Prt Prb otherwise

PNAneg "case 1"

Calculate Y, Dp, and Mp:

D Dw

ts tslab

Case I : Plastic Nuetral Axis in the Steel Web

Y1

D





Pt



Pc



Ps



Prt



Prb



1

2

Pw



th 0

Crt crt Crb crb

DP1 ts th ttf Y1

MP1

Pw
2D

Y12



D



Y1

2



PsPcY1Y1

ts 2



ttf



th



Prt

ts



Crt



ttf 2



Pt



D



Y1

tbf 2



ttf



Y1



th

Prb ts Crb ttf Y1 th



Y1neg



D 2



1



Pc

Pt

Prt Pw

Prb


Dp1neg ts th ttf Y1neg

DCP1neg



D 2Pw





Pt



Pw



Prb



Prt



Pc

A-84

Mp1neg




Pw 2D

Pt



D

Y1neg2
Y1neg



Dw Y1neg 2 Prt ts Crt ttf Y1neg th

tbf 2



Pc



Y1neg



ttf 2

Prb ts Crb ttf Y1neg th




Case II: Plastic Nuetral Axis in the Steel Top Flange

Y2

ttf





Pw



Pt



Ps



Prt



Prb



1

2

Pc



DP2 ts th Y2

MP2

Pc
2ttf

Y22



ttf



Y2

2



Ps



Y2





Pw



D 2

ts 2 ttf

th Prt ts Crt th Y2



Y2



Pt



D



Y2

tbf 2



Prb
ttf

ts



Crb



th



Y2




Y2neg



ttf 2

1



Pw Pc Prt Prb



Pt



DP2neg ts th Y2neg

DCP2neg D

Mp2neg




Pt 2ttf





Y2neg

2





ttf



Y2neg

2



PrPtwtsttf

Crt

th Y2neg

Y2neg



D 2





Prb

Pc



ts Crb ts th

th Y2neg

Y2neg

ttf 2





Case III: Plastic Nuetral Axis in the Concrete Deck Below the Bottom Reinforcing

Y3

ts


Pc



Pw



Pt Ps



Prt



Prb

DP3 Y3

MP3

Ps
2ts





Y32



Prt Y3 Crt



Pt



D



tbf 2

Prb Crb Y3 ttf ts th



Pc



ttf 2

Y3



ts



th

Y3



Pw



D 2



ttf



th

ts



Y3




Case IV: Plastic Nuetral Axis in the Concrete Deck in the bottom reinforcing layer

Y4 Crb

DP4 Y4

MP4

Ps
2ts





Y42



Prt Y4 Crt



Pt



D



tbf 2



Pc



ttf 2

ttf th



th ts

ts
Y4

Y4



Pw



D 2



ttf



th



ts



Y4




Case V: Plastic Nuetral Axis in the Concrete Deck between top and bot reinforcing layers

Y5

ts


Prb



Pc



Pw Ps



Pt



Prt

DP5 Y5

MP5

Ps
2ts





Y52



Prt Y5 Crt



Pt



D



tbf 2

Prb ts Crb
ttf ts th

Y5 Y5



Pc



ttf 2



ts



th

Y5



Pw



D 2



ttf



th

ts



Y5




A-85

Ypos

Y1 if PNApos = "case 1" Y2 if PNApos = "case 2" Y3 if PNApos = "case 3" Y4 if PNApos = "case 4" Y5 if PNApos = "case 5"

DPpos

DP1 if PNApos = "case 1" DP2 if PNApos = "case 2" DP3 if PNApos = "case 3" DP4 if PNApos = "case 4" DP5 if PNApos = "case 5"

MPpos

MP1 if PNApos = "case 1" MP2 if PNApos = "case 2" MP3 if PNApos = "case 3" MP4 if PNApos = "case 4" MP5 if PNApos = "case 5"

Ypos 7.9in

DPpos 7.9in

MPpos 2274.2kipft

Dp = distance from the top of slab of composite section to the neutral axis at the plastic moment (neglect positive moment reinforcement in the slab).

Yneg

Y1neg if PNAneg = "case 1" Y2neg if PNAneg = "case 2"

DPneg

Dp1neg if PNAneg = "case 1" DP2neg if PNAneg = "case 2"

MPneg

Mp1neg if PNAneg = "case 1" Mp2neg if PNAneg = "case 2"

Yneg 11.5in

DPneg 20.1in

MPneg 19361.5kipin

Depth of web in compression at the plastic moment [D6.3.2]:

At bbftbf

Ac btfttf

Dcppos

D FyAt
2



FyAc

0.85fcAslab FyAw



FsAr



1

Dcppos

(0in) if PNApos z "case 1"
(0in) if Dcppos 0
Dcppos if PNApos = "case 1"

Dcppos 0in

Dcpneg

DCP1neg if PNAneg = "case 1" DCP2neg if PNAneg = "case 2"

Dcpneg 19.9in

Positive Flexural Compression Check:

From LRFD Article 6.10.2

Check for compactness:

Web Proportions: Dw d 150 1 tw

Web slenderness Limit:

2 Dcppos d 3.76 Es 1

tw

Fy

S 6.10.6.2.2

Therefore Section is considered compact and shall satisfy the requirements of Article 6.10.7.1.

Mn MPpos if DPpos d 0.1Dt

MPpos 1.07




0.7

DPpos Dt



otherwise

Mn 2123.7kipft

Negative Moment Capacity Check (Appendix A6): Web Slenderness: Dt 40.6in Dcneg Dt ycr tbf 25.4in

2Dcneg 5.7 Es 1

tw

Fy

Moment ignoring concrete:

S Appendix A6 (for skew less than 20 deg).

A-86

Myt FySbotcr 9334.1kipin
My min MycMyt 9334.1kipin
Web Compactness:

Myc FsStopcr

26039.6kipin

Check for Permanent Deformations (6.10.4.2):
Dn max tslab ttf Dw ycyc tslab ttf 28in

Gov if yc tslab ttf yc crtDn 8.5in

fn

M4_SRV_II_neg

Gov Iz



min

1.0

Fy



1

fn

6.2ksi Steel stress on side of Dn



2

Dn

tw Atf

4.2

Rh

12 3 3
(12 2)

1

rw

5.7

Es Fy



Es



PWdcp

minrw


Dcpneg Dcneg


0.54

Fy
MPneg RhMy





2

0.09



22.7

Web Plastification: Flexure Factor:

2 Dcpneg tw

d PWdcp

0

Rpc

MPneg Myc

0.7

f 1.0

Rpt

MPneg Myt

2.1

Tensile Limit: Mr_neg_t fRptMyt 1613.5kipft Compressive Limit:

Local Buckling Resistance:

f

bbf 2tbf

8.5

rf

0.95 0.76 Es Fy

19.9

pf

0.38

Es Fy

9.2

Fyresid

max


min


0.7

Fy

Rh

Fy

Stopcr Sbotcr

Fy


0.5

Fy


35.0 ksi

MncLB

RpcMyc if f d pf





RpcMyc1







1



FyresidStopcr f pf

RpcMyc





rf



pf



otherwise

MncLB 1613.5kipft

Lateral Torsional Buckling Resistance:

Lb

Lstr 23

9.9 ft

rt

bbf

121



1 3



Dcnegtw bbftbf



2.4 in

Inflection point assumed to be at 1/6 span

A-87

Lp

1.0rt

Es Fy

56.7 in

h D tbf 32in

Cb 1.0

Jb

Dtw3



bbf



tbf

3





1



0.63 tbf





btf



ttf

3





1



0.63 ttf



3

3

bbf

3

btf

2.6 in4

Lr

1.95

rt

Es Fyresid



Jb 1 Sbotcrh

1



6.76

Fyresid

Sbotcrh 2

Es

Jb

228.3in

Fcr

Cb2Es
Lb 2

1



0.078

Jb Sbotcrh



Lb 2
rt



rt

MncLTB

RpcMyc if Lb d Lp

116.7ksi


minCb1




1



Fyresid Sbotcr RpcMyc





Lb Lr



Lp Lp





Rpc Myc Rpc Myc





if

Lp Lb d Lr

min FcrSbotcr RpcMyc if Lb ! Lr

MncLTB 1225.3kipft
Mr_neg_c fmin MncLBMncLTB 1225.3kipft
Governing negative moment capacity: Mr_neg

min Mr_neg_t Mr_neg_c

1225.3kipft

12. FLEXURAL STRENGTH CHECKS

Phase 1: First, check the stress due to the dead load on the steel section only. (LRFD 6.10.3 - Constructability Requirements

Reduction factor for construction const 0.9

Load Combination for construction Max Moment applied, Phase 1: (at midspan)
Maximum Stress, Phase 1:

1.25MDC

Mint_P1

1.25

MDC1_int



Lstr 2



277.8kipft (Interior)

Mext_P1

1.25

MDC1_ext

Lstr 2



283.8kipft (Exterior)

fint_P1

M int_P1 y steel Izsteel

12.2 ksi

(Interior)

fext_P1

M ext_P1 y steel Izsteel

12.4 ksi

(Exterior)

Stress limits:

fP1_max constFy

fint_P1 d fP1_max 1 fext_P1 d fP1_max 1

Phase 2: Second, check the stress due to dead load on the composite section (with barriers added)

Reduction factor for construction
Load Combination for construction
Max Moment applied, Phase 2: (at midspan)

const 0.9 1.25MDC
M2_STR_I 403.7kipft

A-88

Capacity for positive flexure: Check Moment:

Mn 2123.7kipft M2_STR_I d constMn 1

Phase 3: Next, check the flexural stress on the stringer during transport and picking, to ensure no cracking.

Reduction factor for construction
Load Combination for construction
Loads and stresses on stringer during transport and picking:

const 0.9 1.5MDC when dynamic construction loads are involved (Section 10).
M3_STR_I_neg 71.2kipft

Concrete rupture stress

fr 0.24 fcksi 0.5ksi

Concrete stress during construction not to exceed:

fcmax constfr 0.5ksi

fcconst

M 3_STR_I_neg y c Izn

fcconst d fcmax 1

0.1 ksi

Phase 4: Check flexural capacity under dead load and live load for fully installed continuous composite girders.

Strength I Load Combination M4_STR_I 919.8kipft M4_STR_I d fMn 1

f 1.0

M4_STR_I_neg 927.6kipft M4_STR_I_neg d Mr_neg 1

Strength III Load Combination M4_STR_III 307kipft
M4_STR_III d fMn 1

M4_STR_III_neg 383.7kipft M4_STR_III_neg d Mr_neg 1

Strength V Load Combination

M4_STR_V 779.7kipft M4_STR_V d fMn 1

M4_STR_V_neg 803.3kipft M4_STR_V_neg d Mr_neg 1

13. FLEXURAL SERVICE CHECKS Check service load combinations for the fully continuous beam with live load (Phase 4): under Service II for stress limits - M4_SRV_II 694.9kipft M4_SRV_II_neg 703.6kipft

under Service I for cracking -

M4_SRV_I_neg 610.4kipft
Ignore positive moment for Service I as there is no tension in the concrete in this case.

Service Load Stress Limits: Top Flange: ftfmax 0.95RhFy 47.5ksi Bottom Flange: fbfmax ftfmax 47.5ksi Concrete (Negative bending only): fr 0.5ksi
Service Load Stresses, Positive Moment:

A-89

Top Flange: Bottom Flange:

fSRVII_tf

M4_SRV_II

yc tslab Iz

fSRVII_tf d ftfmax 1

2.9 ksi

fbfs2

M4_SRV_II

tslab ttf Dw tbf yc Iz

fl 0

fbfs2

fl 2

d fbfmax

1

20.7 ksi

Service Load Stresses, Negative Moment:

Top (Concrete):

fcon.neg

M 4_SRV_I_neg y cneg nIzneg

1.3 ksi

Using Service I Loading

Bottom Flange: Check LL Deflection:

fcon.neg d fr 0

fbfs2.neg

M4_SRV_I_neg tslab ttf Dw tbf ycneg
Izneg

fbfs2.neg d fbfmax 1

32.3 ksi

DT 1.104in

DF

3 12

Lstr

DTDF

0.3 2587

from independent Analysis - includes 100% design truck (w/impact), or 25% design truck (w/impact) + 100% lane load Deflection distribution factor = (no. lanes)/(no. stringers)
Equivalent X, where L/X = Deflection*Distribution Factor

Lstr t 800 1 DTDF

14. SHEAR STRENGTH Shear Capacity based on AASHTO LRFD 6.10.9

Nominal resistance of unstiffened web:

Fy 50.0ksi

Dw 31.4in

Vp 0.58FyDwtw 428.0kip

tw 0.5in

v 1.0

k 5

A-90

C1

1.0 if Dw d 1.12 Esk

tw

Fy

1.57





Es

k



if

Dw ! 1.40

Esk

Dw 2 Fy tw

Fy





tw



1.12 Dw tw

Esk Fy


otherwise

Vn C1Vp 386.4kip

Vu d vVn 1

C1 0.903

15. FATIGUE LIMIT STATES:

Fatigue check shall follow LRFD Article 6.10.5. Moments used for fatigue calculations were found using an outside finite element analysis program.

First check Fatigue I (infinite life); then find maximum single lane ADTT for Fatigue II if needed.

Fatigue Stress Limits:

FTH_1 FTH_2 FTH_3

16ksi 12ksi 10ksi

Category B: non-coated weathering steel Category C': Base metal at toe of transverse stiffener fillet welds Category C: Base metal at shear connectors

Fatigue Moment Ranges at Detail Locations (from analysis):

MFAT_B 301kipft

MFAT_CP 285.7kipft

FATI 1.5

FATII 0.75

Constants to use for detail checks:

ADTTSL_INF_B 860 ADTTSL_INF_CP 660 ADTTSL_INF_C 1290

AFAT_B 120108 AFAT_CP 44108 AFAT_C 44108

MFAT_C 207.1kipft nfat 2 if Lstr d 40ft 1.0 otherwise

Category B Check: Stress at Bottom Flange, Fatigue I

fFATI_B

FATIMFAT_B tslab ttf Dw tbf yc
Iz

fFATI_B d FTH_1 1

fFATII_B

FATII FATI



fFATI_B

6.7 ksi

13.5 ksi

A-91

ADTTSL_B_MAX

ADTTSL_INF_B nfat

if fFATI_B d FTH_1

ADTTSL_B_MAX 860

AFAT_Bksi3 36575nfatfFATII_B3

otherwise

Category C' Check: Stress at base of transverse stiffener (top of bottom flange)

fFATI_CP

FATIMFAT_CP

tslab ttf Dw yc Iz

12.5 ksi

fFATI_CP d FTH_2 0

fFATII_CP

FATII FATI



fFATI_CP

6.2 ksi

ADTTSL_CP_MAX

ADTTSL_INF_CP nfat

if fFATI_CP d FTH_2

ADTTSL_CP_MAX 659

AFAT_CPksi3 36575nfatfFATII_CP3

otherwise

Category C Check: Stress at base of shear connectors (top of top flange)

fFATI_C

FATIMFAT_C

yc tslab Iz

1.3 ksi

fFATI_C d FTH_3 1

fFATII_C

FATII FATI



fFATI_C

0.6 ksi

ADTTSL_C_MAX

ADTTSL_INF_C nfat

if fFATI_C d FTH_3

ADTTSL_C_MAX

AFAT_Cksi3 36575nfatfFATII_C3

otherwise

1290

FATIGUE CHECK: ADTTSL_MAX min ADTTSL_B_MAX ADTTSL_CP_MAXADTTSL_C_MAX

Ensure that single lane ADTT is less than ADTTSL_MAX 659 If not, then the beam requires redesign.

A-92

16. BEARING STIFFENERS Using LRFD Article 6.10.11 for stiffeners:

tp

5 in
8

bp 5in

b 1.0

Projecting Width Slenderness Check:

bp d 0.48tp

Es Fy

1

Stiffener Bearing Resistance:

tp_weld



5 16



in

*Check min weld size

Apn 2 bp tp_weld tp

Apn 5.9in2

Rsb_n 1.4ApnFy

Rsb_n 410.2kip

Rsb_r bRsb_n

Rsb_r 410.2kip

RDC 26.721kip RDW 2.62kip RLL 53.943kip

DC_STR_I 1.25 DW_STR_I 1.5 LL_STR_I 1.75

Ru DC_STR_IRDC DW_STR_IRDW LL_STR_IRLL

Ru d Rsb_r 1

Weld Check:

throat

tp_weld

2 2

Lweld Dw 23in

Aeff_weld throatLweld

Fexx 70ksi

e2 0.8

Rr_weld 0.6e2Fexx

Ru_weld

Ru 4Aeff_weld

Ru_weld d Ru_weld 1

Axial Resistance of Bearing Stiffeners:

Aeff 29tw tp tw 2bptp

Leff 0.75Dw

Ixp

29twtw3 tp 2bp tw 3

12

12

Iyp

tw tp 29tw 3 2bptp3

12

12

rp

min IxpIyp
Aeff

Q 1

for bearing stiffeners

c 0.9 Kp 0.75

9tw x tw

bp x tp 9tw x tw

bp x tp

Ru 131.7kip
throat 0.2in Lweld 25.4in Aeff_weld 5.6in2 Rr_weld 33.6ksi Ru_weld 5.9ksi
Aeff 10.5in2 Leff 23.6in Ixp 59.9in4 Iyp 29.6in4 rp 1.7in

Po QFyAeff 526kip

A-93

Pe

2EsAeff



Kp

Leff rp



2

27132.1kip





Po



Pn

0.658 Pe Po

if

Pe

t

0.44

Po

0.877Pe otherwise

Pr cPn

Pr 469.6kip

Ru d Pr 1

17. SHEAR CONNECTORS:

Shear Connector design to follow LRFD 6.10.10.

Stud Properties:

ds

7 in Diameter 8

hs 6in Height of Stud

cs tslab hs

cs t 2in 1

hs t 4 1 ds

ss 3.5in Spacing

ss t 4ds 1

ns 3 Studs per row

Asc

ds 2 2

btf ss ns 1 ds t 1.0in 1 2

Fu 60ksi

Fatigue Resistance:

Zr

5.5d

s2

kip in2

Zr 4.2kip

Qslab Aslab yc yslab

Vf 47.0kip

Vfat

VfQslab Iz

1.3 kip in

ps

nsZr Vfat

9.7 in

6ds d ps d 24in 1

Strength Resistance:

sc 0.85
fc 5ksi Ec 330000.151.5 fc ksi

4286.8 ksi

Qn min 0.5Asc fcEcAscFu

Qr scQn

Psimple min 0.85fcbefftsFyAsteel

Pcont Psimple min 0.45fcbefftsFyAsteel

nlines

Pcont Qrns

Pn 521.7kip
Asc 0.6in2 Qslab 318.7in3
Qn 36.1kip Qr 30.7kip Psimple 1190kip Pcont 1820kip nlines 19.8

A-94

Find required stud spacing along the girder (varies as applied shear varies)

i 0 23

0.00



1.414



4.947

8.480 12.013

15.546



19.079



22.612

26.145



29.678



33.210

33.917

x



ft

34.624

Vfi

36.037



36.743



40.276

43.809



47.342



50.875

54.408 57.941

61.474



65.007



67.833

61.5



59.2



56.8

54.4 52.0

49.5



47.1



44.7

42.7



40.6



40.6

40.6 kip 40.6

40.6



40.6



42.3

44.2



46.6



49.1

51.5 53.9

56.3



58.7



61.5

0

0 1.7

1 1.6

2 1.6

3 1.5

4 1.4

5 1.4

Vfati

VfiQslab Iz

6 7 8

1.3 1.2 kip
in 1.2

9 1.1

10 1.1

11 1.1

12 1.1

13 1.1

14 1.1

15 ...

0

0 7.4

1 7.7

2 8.1

3 8.4

4 8.8

5 9.2

Pmax

nsZr Vfati

6 7 8

9.7 10.2 in 10.7

9 11.3

10 11.3

11 11.3

12 11.3

13 11.3

14 11.3

15

...

min Pmax 7.4in max Pmax 11.3in

18. SLAB PROPERTIES

This section details the geometric and material properties of the deck. Because the equivalent strip method is used in accordance with AASHTO LRFD Section 4, different loads are used for positive and negative bending.

Unit Weight Concrete Deck Thickness for Design Deck Thickness for Loads

wc 150pcf tdeck 8.0in td 10.5in

tdeck t 7in 1

Rebar yield strength

Fs 60ksi

Strength of concrete

fc 5ksi

Concrete clear cover

Bottom cb 1.0in

cb t 1.0in 1

Top ct 2.5in

ct t 2.5in 1

A-95

Transverse reinforcement

Bottom Reinforcing tb

6 in
8

Bottom Spacing stb 8in

stb t 1.5tb 1.5in 1

Design depth of Bar Girder Spacing

stb d 1.5tdeck 18in 1

Astb

12in tb 2 stb 2

0.7 in2

dtb

tdeck





cb



tb 2

6.6 in

spacingint_max 2ft 11in

spacingext 3 ft

Equivalent Strip, +M

wposM

26 6.6 spacingint_max in



ft



Equivalent Strip, -M

wnegM

48 3.0 spacingint_max in



ft



Once the strip widths are determined, the dead loads can be calculated.

Top Reinforcing Top Spacing

tt

5 in
8

stt 8in

stt t 1.5tt 1.5in 1

stt d 1.5tdeck 18in 1

Astt

12in tt 2 stt 2

0.5 in2

dtt

tdeck





ct



tt 2

5.2 in

wposM 45.3in wnegM 56.8in

19. PERMANENT LOADS

This section calculates the dead loads on the slab. These are used later for analysis to determine the design moments.

Weight of deck, +M

wdeck_pos wctdwposM

wdeck_pos 494.9plf

Weight of deck, -M

wdeck_neg wctdwnegM

wdeck_neg 620.7plf

Unit weight of barrier

wb 433.5plf

Barrier point load, +M

Pb_pos wbwposM

Pb_pos 1.63kip

Barrier point load, -M

Pb_neg wbwnegM

Pb_neg 2.05kip

20. LIVE LOADS

This section calculates the live loads on the slab. These loads are analyzed in a separate program with the permanent

loads to determine the design moments.

Truck wheel load

Pwheel 16kip

Impact Factor

IM 1.33

Multiple presence factors Wheel Loads

MP1 1.2 P1 IMMP1Pwheel

MP2 1.0 P2 IMMP2Pwheel

MP3 0.85 P3 IMMP3Pwheel

P1 25.54kip

P2 21.3kip

P3 18.09kip

21. LOAD RESULTS
The separate MathCAD design aides (available in Appendix of the final report) was used to analyze the deck as an 11-span continuous beam without cantilevered overhangs on either end, with supports stationed at girder locations. The dead and live loads were applied separately. The results are represented here as input values, highlighted.
Design Moments

A-96

Mpos_deck 0.4kipft Mpos_LL 15.3kipft

Mpos 1.25Mpos_deck 1.75Mpos_LL

Mpos 27.3kipft

Mpos_dist

Mpos wposM

Mpos_dist

7.23 kipft ft

Mneg_deck 0.6kipft Mneg_LL 7.8kipft

Mneg 1.25Mneg_deck 1.75Mneg_LL

Mneg 14.4kipft

Mneg_dist

Mneg wnegM

Mneg_dist

3.04 kipft ft

22. FLEXURAL STRENGTH CAPACITY CHECK:

Consider a 1'-0" strip:

b 0.9

b 12in

1 0.85 if fc d 4ksi
0.85 0.05 fc 4 otherwise ksi

1 0.8

Bottom:

ctb

AstbFs 0.85fc1b

1 in

atb 1ctb 0.8in

Mntb Mrtb

Astb b

Fs





dtb



atb 2

bMntb

18.6 kipft ft

20.7 kipft ft

Mrtb t Mpos_dist 1

Top: ctt att

AsttFs 0.85fc1b

0.7 in

1ctt 0.5in

Mntt Mrtt

Astt ft

Fs





dtt



att 2

11.3 kipft ft

bMntt

10.2 kipft ft

Mrtt t Mneg_dist 1

23. LONGITUDINAL DECK REINFORCEMENT DESIGN:

Longitudinal reinforcement
Distribution Reinforcement (AASHTO 9.7.3.2)

lb

5 in
8

slb 12in

Aslb

12in lb 2 slb 2

0.3 in2

A%dist

min

220 spacingint_max

67

ft



100

Adist A%dist Astb 0.4in2

lt

5 in
8

slt 12in

Aslt

12in lt 2 slt 2

0.3 in2

67 % Aslb Aslt t Adist 1

A-97

24. DESIGN CHECKS

This section will conduct design checks on the reinforcing according to various sections in AASHTO LRFD.

CHECK MINIMUM REINFORCEMENT (AASHTO LRFD 5.7.3.3.2):

Modulus of Rupture Section Modulus

fr 0.37 fcksi 0.8ksi

Snc

btdeck2 6

Adeck tdeckb

128 in3 96 in2

Ec 4286.8ksi Es 29000ksi

A-98

ybar_tb

Adeck

tdeck 2



(n



1)Astbdtb

Adeck (n 1)Astb

4.1 in

Unfactored Dead Load Cracking Moment
Minimum Factored Flexural Resistance

ybar_tt

Adeck

tdeck 2



(n

1)Asttdtt

Adeck (n 1)Astt

4 in

Itb

btdeck3 12



Adeck



tdeck 2



ybar_tb2

(n



1)Astb

dtb



ybar_tb

2

538.3in4

Itt

btdeck3 12



Adeck



tdeck 2



ybar_tt2

(n



1)Astt

dtt



ybar_tt

2

515.8in4

Sc_tb

Itb tdeck ybar_tb

138.2in3

Sc_tt

Itt tdeck ybar_tt

130 in3

Mdnc_pos_t

kipft 1.25
ft

Mdnc_neg_t

0.542 kipft ft

Mcr_tb

Sc_tb fr max



ft

Mdnc_pos_t





Sc_tb

Snc



1

Sc_tb

fr

ft

9.5 kipft ft

Mcr_tt

Sc_tt fr max



ft

Mdnc_neg_t





Sc_tt

Snc



1

Sc_tt

fr

ft

9 kipft ft

S 5.7.3.3.2

Mr_min_tb Mr_min_tt

min 1.2Mcr_tb 1.33 Mpos_dist min 1.2Mcr_tt1.33 Mneg_dist

9.6 kipft ft
4 kipft ft

Mrtb t Mr_min_tb 1 Mrtt t Mr_min_tt 1

CHECK CRACK CONTROL (AASHTO LRFD 5.7.3.4): eb 1.0

MSL_pos 29.64kipft

MSL_pos_dist

MSL_pos wposM

fssb

MSL_pos_distbn Itb

dtbybar_tb

dcb

cb

tb 2

1.4 in

7.9 kipft ft
3.1 ksi

et 0.75

MSL_neg 29.64kipft

MSL_neg_dist

MSL_neg wnegM

fsst

MSL_neg_distbn Itt

dttybar_tt

dct

ct

tt 2

2.8 in

6.3 kipft ft
1.2 ksi

sb

1

dcb

0.7 tdeck dcb

1.3

sb

700ebkip sbfssbin



2dcb

171.9in

stb d sb 1

st

1

dct

0.7 tdeck dct

1.8

st

700etkip stfsstin



2dct

245.5in

stt d st 1

A-99

SHRINKAGE AND TEMPERATURE REINFORCING (AASHTO LRFD 5.10.8):

Ast

1.30btdeck kip if 0.11in2 d 1.30btdeck kip d 0.60in2

2 b tdeck Fs in

2 b tdeck Fs in

0.11in2 if 1.30btdeck kip 0.11in2 2 b tdeck Fs in

0.60in2 if 1.30btdeck kip ! 0.60in2 2 b tdeck Fs in

0.1 in2

Astb t Ast 1 Aslb t Ast 1

Astt t Ast 1 Aslt t Ast 1

SHEAR RESISTANCE (AASHTO LRFD 5.8.3.3):

0.9

2

45deg

b 1 ft

dv_tb

max

0.72

tdeck

dtb



atb 2

0.9d

tb

6.2 in

dv_tt

max

0.72

tdeck

dtt



att 2

0.9d

tt

5.8 in

dv min dv_tbdv_tt 5.8in

Vc 0.0316 fcksibdv 9.8kip

Vs 0kip Shear capacity of reinforcing steel

Vps 0kip Shear capacity of prestressing steel
Vns min Vc Vs Vps0.25fcbdv Vps 9.8kip

Vr Vns 8.8kip Total factored resistance

Vus 8.38kip

Total factored load

Vr t Vus 1

DEVELOPMENT AND SPLICE LENGTHS (AASHTO LRFD 5.11):

Development and splice length design follows standard calculations in AASHTO LRFD 5.11, or as dictated by the State DOT Design Manual.

25. DECK OVERHANG DESIGN (AASHTO LRFD A.13.4):

A-100

Deck Properties:

Deck Overhang Length Parapet Properties:

Lo 1ft 9in

Note: Parapet properties are per unit length. Compression reinforcement is ignored.

Cross Sectional Area

Ap 2.84ft2

Height of Parapet

Hpar 2ft 10in

Parapet Weight Width at base

Wpar wcAp 426plf wbase 1ft 5in Average width of wall

wwall

13in 9.5in 2

11.3 in

Height of top portion of parapet Height of middle portion of parapet Height of lower portion of parapet

h1 2ft h2 7in h3 3in

Width at top of parapet

width1 9.5in 9.5in

Width at middle transition of parapet Width at base of parapet

width2 12in 12in width3 1ft 5in 17in

Parapet Center of Gravity

b1 width1

b2 width2 width1

b3 width3 width2

h1

h2

h3

b12 2



1 2



h1

b2



b1



b2 3



CGp

h2

h3 b2

b3





b1



b2 2

b3



1 2



h2

b3



b1



b2

2b3 3

h1

h2

h3

b1

1 2

h1b2



h2 h3 b2 b3



1 2



h2

b3

6.3 in

Parapet Reinforcement Rebar spacing: Rebar Diameter:
Rebar Area:

Vertically Aligned Bars in Wall spa 12in

pa

5 in
8

Ast_p





pa



2

b

2 spa

0.3 in2

Horizontal Bars npl 5

pl

5 in
8

Asl_p

pl 2 2

0.3 in2

Cover:
Effective Depth:
Parapet Moment Resistance About Horizontal Axis:
Depth of Equivalent Stress Block:

cst 3in

dst

wbase

cst

pa 2

13.7 in

ext 1.0

ah

Ast_pFs 0.85fcb

0.4 in

csl 2in pa 2.6in

dsl

wwall

csl

pl 2

8.3 in

S 5.7.3.1.2-4 S 5.7.3.2.3

Moment Capacity of Upper Segment of Barrier (about longitudinal axis):

Average width of section Cover
Depth

w1 cst1
dh1

width1 width2

2 2in

w1

cst1



pa 2

10.7 in 8.4 in

Factored Moment Resistance

Mnh1

ext

Ast_pFs



dh1



ah 2

b

12.7 kipft ft

Moment Capacity of Middle Segment of Barrier (about longitudinal axis):

A-101

Average width of section Cover
Depth
Factored Moment Resistance

w2

width2 width3 2

cst2 3in

14.5 in

dh2

w2

cst2



pa 2

11.2 in

Mnh2

ext

Ast_pFs



dh2



ah 2

b

Parapet Base Moment Resistance (about longitudinal axis):

16.9 kipft ft

development in tension

cst3 3in minc_ta 1.5 if cst3 3pa spa pa 6pa

coverbase_vert 1.2

cst3

pa 2

1.2 otherwise

mdec_ta 0.8 if spa t 6in 0.8

1.0 otherwise

ldb_ta

max


1.25inAst_p fc

Fs kip

0.4pa

Fs ksi

if

pa d

11 in
8



ksi



2.70in Fs ksi
fc

if

pa =

14 in
8

ksi

3.50in Fs ksi
fc ksi

if

pa =

18 in
8

hooked bar developed in tension

ldt_ta lhb_ta

l db_ta minc_ta mdec_ta

38pa fc

10.6 in

ksi

14.4 in

minc 1.2

lap splice in tension

ldh_ta max 6in8paminclhb_ta 12.7in llst_ta max 12in1.3ldt_ta 18.7in

benefit ldt_ta ldh_ta 1.7in

ldev_a

7



13 16

in

Fdev

benefit ldev_a ldt_ta

0.7

Fd 0.75

Distance from NA to Compressive Face

ct_b

FdAst_pFs 0.85fc1b

0.3 in

S 5.7.3.1.2-4

3.3 in

A-102

Depth of Equivalent Stress Block
Nominal Moment Resistance

at 1ct_b 0.3in

Mnt

Fd

Ast_p

Fs



dst



at 2

15.6kipft

S 5.7.3.2.3 S 5.7.3.2.2-1

Factored Moment Resistance

Mcb

ext

Mnt ft

15.6 kipft ft

S 5.7.3.2

Average Moment Capacity of Barrier (about longitudinal axis):

Factored Moment Resistance about Horizontal Axis

Mc

Mnh1h1 Mnh2h2 Mcbh3 h1 h2 h3

13.8 kipft ft

Parapet Moment Resistance (about vertical axis):

Height of Transverse

y1 5in

Reinforcement in Parapet

y2 11.5in

y3 18in

y4 24.5in

y5 31in

Depth of Equivalent Stress a nplAsl_pFs

Block

0.85fcHpar

Concrete Cover in Parapet coverr 2in

Width of Parapet at
Transverse Reinforcement

x1

width3

y1 h3 b3 h2

15.6 in

x2

b1 b2

y2 h3 h2 b2 h1

11.8 in

x3

b1 b2

y3 h3 h2 b2 h1

11.2 in

x4

b1 b2

y4 h3 h2 b2 h1

10.5 in

x5

b1 b2

y5 h3 h2 b2 h1

9.8 in

0.6 in

coverrear

coverr

pa

pl 2

2.9 in

coverbase

cst3



pa

pl 2

3.9 in

coverf 2in

covert

x5 2

4.9 in

coverfront

2in

pa

pl 2

covertop covert 4.9in

Design depth

d1i x1 coverbase 11.6in

d1o x1 coverrear 12.6in

d2i x2 coverfront 8.9in

d2o x2 coverrear 8.9in

d3i x3 coverfront 8.2in

d3o x3 coverrear 8.2in

d4i x4 coverfront 7.6in

d4o x4 coverrear 7.6in

d5i x5 covertop 4.9in

d5o x5 covertop 4.9in

Nominal Moment Resistance - Tension on Inside Face

Mn1i Mn2i

ext Asl_p Fs d 1i



a 2



ext Asl_p Fs d 2i



a 2



208.3kipin 158.1kipin

Mn3i

ext Asl_p Fs d 3i



a 2



145.6kipin

Mn4i

ext Asl_p Fs d 4i



a 2



133.2kipin

A-103

Nominal Moment Resistance - Tension on Outside Face
Vertical Nominal Moment Resistance of Parapet Parapet Design Factors: Crash Level Transverse Design Force

Mn5i

ext Asl_p Fs d 5i



a 2



84.5kipin

Mwi Mn1i Mn2i Mn3i Mn4i Mn5i

Mn1o

extAsl_pFsd1o

a 2



18.9kipft

Mn2o

extAsl_pFsd2o

a 2



13.2kipft

Mn3o

extAsl_pFsd3o

a 2



12.1kipft

Mn4o

extAsl_pFsd4o

a 2



11.1kipft

60.8kipft

Mn5o

extAsl_pFsd5o

a 2



7kipft

Mwo Mn1o Mn2o Mn3o Mn4o Mn5o

62.3kipft

Mw

2Mwi Mwo 3

61.3kipft

CL "TL-4" Ft 13.5kip if CL = "TL-1"
27.0kip if CL = "TL-2" 54.0kip if CL = "TL-3" 54.0kip if CL = "TL-4" 124.0kip if CL = "TL-5" 175.0kip otherwise

54 kip

Lt 4.0ft if CL = "TL-1" 4.0ft if CL = "TL-2" 4.0ft if CL = "TL-3" 3.5ft if CL = "TL-4" 8.0ft if CL = "TL-5" 8.0ft otherwise

3.5 ft

Longitudinal Design Force Fl 4.5kip if CL = "TL-1" 9.0kip if CL = "TL-2" 18.0kip if CL = "TL-3" 18.0kip if CL = "TL-4" 41.0kip if CL = "TL-5"

58.0kip otherwise

Vertical Design Force (Down)

Fv 4.5kip if CL = "TL-1" 4.5kip if CL = "TL-2" 4.5kip if CL = "TL-3" 18.0kip if CL = "TL-4" 80.0kip if CL = "TL-5"

80.0kip otherwise

Critical Length of Yield Line Failure Pattern:

Mb 0kipft

18 kip 18 kip

Ll 4.0ft if CL = "TL-1" 4.0ft if CL = "TL-2" 4.0ft if CL = "TL-3" 3.5ft if CL = "TL-4" 8.0ft if CL = "TL-5" 8.0ft otherwise

3.5 ft

Lv 18.0ft if CL = "TL-1" 18ft 18.0ft if CL = "TL-2" 18.0ft if CL = "TL-3" 18.0ft if CL = "TL-4" 40.0ft if CL = "TL-5" 40.0ft otherwise

A-104

Lc

Lt 2

Lt 2 8Hpar Mb Mw

2

Mc

11.9 ft

S A13.3.1-2

Rw

2 2Lc

Lt 8Mb

8Mw

McLc2 Hpar

T

Rwb

Lc 2Hpar

6.6 kip

116.2kip

S A13.3.1-1 S A13.4.2-1

The parapet design must consider three design cases. Design Case 1 is for longitudinal and transverse collision loads under Extreme Event Load Combination II. Design Case 2 represents vertical collision loads under Extreme Event Load Combination II; however, this case does not govern for decks with concrete parapets or barriers. Design Case 3 is for dead and live load under Strength Load Combination I; however, the parapet will not carry wheel loads and therefore this case does not govern. Design Case 1 is the only case that requires a check.

Design Case 1: Longitudinal and Transverse Collision Loads, Extreme Event Load Combination II

DC - 1A: Inside face of parapet ext 1

DC 1.0

DW 1.0

LL 0.5

S A13.4.1 S Table 3.4.1-1

llip 2in
Adeck_1A tdeck llip wbase

152 in2

wbase 17in Ap 2.8ft2

Wdeck_1A wcAdeck_1A 0.2klf

MDCdeck_1A

DCWdeck_1A

llip

wbase 2

Wpar 0.1 kipft
ft

MDCpar_1A DCWpar llip CGp

0.3 kipft ft

Mtotal_1A Mcb MDCdeck_1A MDCpar_1A

16 kipft ft

0.4 klf

tt_add

5 in
8

stt_add 8in

Astt_p

12in tt 2 12in tt_add 2 stt 2 stt_add 2

0.9 in2

dtt_add

tdeck



ct



tt_add 2

ctt_p

Astt_pFs 0.85fc1b

1.4 in

5.2 in

att_p 1ctt_p 1.1in

Mntt_p

Astt_pFs ft





dtt_add



att_p 2

21.4 kipft ft

Mrtt_p bMntt_p

19.2 kipft ft

AsT Astt Astb 1.1in2

Mrtt_p t Mtotal_1A 1

Pn extAsTFs 67.4kip

Pn t T 1

Mu_1A

Mrtt_p 1



T Pn



17.4 kipft ft

Mu_1A t Mtotal_1A 1

A-105

DC - 1B: Design Section in Overhang

Notes:

Distribution length is assumed to increase based on a 30 degree angle from the face of parapet.

Moment of collision loads is distributed over the length Lc + 30 degree spread from face of parapet to

location of overhang design section.

Axial force of collision loads is distributed over the length Lc + 2Hpar + 30 degree spread from face of

parapet to location of overhang design section.

Future wearing surface is neglected as contribution is negligible.

Adeck_1B tdeckLo 168in2

Ap 2.8ft2

Wdeck_1B wcAdeck_1B 0.2klf

Wpar

MDCdeck_1B

DC

Wdeck_1B

Lo 2

0.2 kipft ft

MDCpar_1B DCWpar Lo llip CGp

0.5 kipft ft

0.4 klf

Lspread_B Lo llip width3 2in

spread 30deg

wspread_B Lspread_Btan(spread) 1.2in

Mcb_1B

McbLc Lc 2wspread_B

15.3 kipft ft

Mtotal_1B Mcb_1B MDCdeck_1B MDCpar_1B

15.9 kipft ft

Mrtt_p

19.2 kipft ft

Mrtt_p t Mtotal_1B 1

Pn 67.4kip

Pu

T Lc 2Hpar Lc 2Hpar 2wspread_B

6.5 kip

Pn t Pu 1

Mu_1B

Mrtt_p 1




Pu

Pn



17.4 kipft ft

Mu_1B t Mtotal_1B 1

DC - 1C: Design Section in First Span

Assumptions: Moment of collision loads is distributed over the length Lc + 30 degree spread from face of

parapet to location of overhang design section.

Axial force of collision loads is distributed over the length Lc + 2Hpar + 30 degree spread from

face of parapet to location of overhang design section.

Future wearing surface is neglected as contribution is negligible.

Mpar_G1 MDCpar_1B

0.5 kipft ft

Mpar_G2

0.137 kipft ft

(From model output)

M1 Mcb

15.6 kipft ft

M2

M1

Mpar_G2 Mpar_G1

4.7 kipft ft

bf 10.5in

Mc_M2M1

M1

1 4



bf



M1



M2

spacingint_max

14.1 kipft ft

A-106

Lspread_C wspread_C

Lo

llip



wbase



bf 4

Lspread_Ctan(spread)

4.6 in 2.7 in

Mcb_1C

Mc_M2M1Lc Lc 2wspread_C

13.6 kipft ft

Mtotal_1C Mcb_1C MDCdeck_1B MDCpar_1B

14.2 kipft ft

Mrtt_p

19.2 kipft ft

Mrtt_p t Mtotal_1C 1

Pn 67.4kip

PuC

T Lc 2Hpar Lc 2Hpar 2wspread_C

6.4 kip

Pn t PuC 1

Mu_1C

Mrtt_p 1




Pu

Pn



17.4 kipft ft

Mu_1B t Mtotal_1B 1

Compute Overhang Reinforcement Cut-off Length Requirement

Maximum crash load moment at theoretical cut-ff point:

Mc_max Mrtt

10.2 kipft ft

LMc_max

M2 M2



Mrtt M1



spacingint_max

2.1 ft

Lspread_D Lo llip wbase LMc_max 27.7in

wspread_D Lspread_Dtan(spread) 16in

Mcb_max

Mc_maxLc Lc 2wspread_D

8.3 kipft ft

extension max dtt_add12tt_add0.0625spacingint_max

cutt_off LMc_max extension

Att_add

tt_add 2 2

0.3 in2

33.2 in

mthick_tt_add 1.4 if tdeck ct t 12in 1

7.5 in

1.0 otherwise

mepoxy_tt_add

1.5

if

ct

3tt_add

stt_add 2



tt_add 6tt_add

1.5

1.2 otherwise

minc_tt_add min mthick_tt_addmepoxy_tt_add 1.7 1.5

mdec_tt_add

0.8 if stt_add t 6in 2

1

1.0 otherwise

A-107

ldb_tt_add

max


1.25inAtt_add fc

Fs kip

0.4tt_add

Fs ksi

if

tt_add d

11 in
8



ksi



2.70in Fs ksi
fc

if

tt_add =

14 in
8

ksi

ldb_tt_add 15in

3.50in Fs ksi
fc ksi

if

tt_add =

18 in
8

ldt_tt_add ldb_tt_addminc_tt_addmdec_tt_add 22.5in Cuttoffpoint LMc_max ldt_tt_add spacingint_max 13.2in extension past second interior girder

Check for Cracking in Overhang under Service Limit State: Does not govern - no live load on overhang.

25. COMPRESSION SPLICE:

See sheet S7 for drawing.

Ensure compression splice and connection can handle the compressive force in the force couple due to the negative moment over the pier.

Live load negative moment over pier:

MLLPier 541.8kipft

Factored LL moment:

MUPier 1.75MLLPier 948.1kipft

The compression splice is comprised of a splice plate on the underside of the bottom flange, and built-up angles on either side of the web, connecting to the bottom flange as well.

Calculate Bottom Flange Stress:

Composite moment of inertia:

Iz 11538.5in4

Distance to center of bottom flange from composite section centroid: Stress in bottom flange:
Calculate Bottom Flange Force: Design Stress:
Effective Flange Area:

ybf

tbf 2



Dw

ttf



tslab

yc

fbf

MUPier

ybf Iz

28 ksi

28.3 in

Fbf

max

fbf

2

Fy

0.75Fy

Aef bbftbf 6.3in2

39 ksi

Force in Flange:

Cnf FbfAef 247.3kip

Calculate Bottom Flange Stress, Ignoring Concrete:

Moment of inertia:

Izsteel 4463.1in4

Distance to center of bottom flange:

ybfsteel

tbf 2



Dw

ttf



ysteel

16 in

A-108

Stress in bottom flange:
Bottom Flange Force for design: Design Stress: Design Force:

fbfsteel

MUPier

ybfsteel Izsteel

40.8 ksi

Fcf

max

fbfsteel 2



Fy

0.75Fy

Cn max Fbf Fcf Aef 288kip

45.4 ksi

Compression Splice Plate Dimensions:

Bottom Splice Plate:

bbsp bbf 10.4in

tbsp 0.75in

Built-Up Angle Splice Plate Horizontal Leg: Built-Up Angle Splice Plate Vertical Leg:

basph 4.25in baspv 7.75in

tasph 0.75in taspv 0.75in

Total Area:

Acsp Absp Aasph Aaspv 25.8in2

Average Stress:

fcs

Proportion Load into each plate based on area:

Cn Acsp

11.2 ksi

Absp bbsptbsp 7.8in2 Aasph 2basphtasph 6.4in2 Aaspv 2baspvtaspv 11.6in2

Cbsp

CnAbsp Acsp

87.1 kip

Casph

CnAasph Acsp

71.2 kip

Caspv

CnAaspv Acsp

129.8kip

Check Plates Compression Capacity:

Bottom Splice Plate:

kcps 0.75 for bolted connection

lcps 9in

rbsp Pebsp

min

bbsp

tbsp3

tbsp

bbsp3



12

12

Absp

2EsAbsp

kcpslcps 2





rbsp

2296.8 kip

0.2 in

Qbsp

1.0 if bbsp d 0.45 Es

tbsp

Fy

1.34



0.76

bbsp





Fy

if 0.45

Es d bbsp d 0.91

Es



tbsp Es

Fy tbsp

Fy

0.53Es

Fy



bbsp tbsp



2

otherwise

Pobsp QbspFyAbsp 351.9kip

0.902

A-109

Pnbsp





Pobsp





0.658 Pebsp Pobsp

if

Pebsp t 0.44 Pobsp

0.877Pebsp otherwise

Pnbsp_allow 0.9Pnbsp 297.1kip

Check

330.1kip
"NG" if Cbsp t Pnbsp_allow "OK" if Pnbsp_allow t Cbsp

"OK"

Horizontal Angle Leg:

kcps 0.75 lcps 9in

for bolted connection

rasph Peasph

min

basph

tasph3

tasph

basph3



12

12

Aasph

2EsAasph

kcpslcps 2





rasph

938.6kip

0.153in

Qasph

1.0 if basph d 0.45 Es

tasph

Fy

1

1.34



0.76

basph





Fy

if 0.45

Es d basph d 0.91

Es



tasph Es

Fy tasph

Fy

0.53Es

Fy



basph tasph



2

otherwise

Poasph QasphFyAasph 318.7kip

Vertical Angle Leg:

Pnasph





Poasph





0.658 Peasph Poasph

if

Peasph t 0.44 Poasph

276.5kip

0.877Peasph otherwise

Pnasph_allow 0.9Pnasph 248.9kip

Check2 "NG" if Casph t Pnasph_allow

kcps 0.75 for bolted connection

"OK" if Pnasph_allow t Casph

lcps 9in

raspv

min

baspv

taspv3

taspv

baspv3



12

12

Aaspv

0.153in

Peaspv

2EsAaspv

kcpslcps 2





raspv

1711.6 kip

"OK"

A-110

Qaspv

1.0 if baspv d 0.45 Es

taspv

Fy

1

1.34



0.76

baspv





Fy

if 0.45

Es d baspv d 0.91

Es



taspv Es

Fy taspv

Fy

0.53Es

Fy



baspv taspv



2

otherwise

Poaspv QaspvFyAaspv 581.2kip

Pnaspv





Poaspv





0.658 Peaspv Poaspv

if

Peaspv t 0.44 Poaspv

504.2kip

0.877Peaspv otherwise

Pnaspv_allow 0.9Pnaspv 453.8kip

Check3 "NG" if Caspv t Pnaspv_allow

"OK" if Pnaspv_allow t Caspv

"OK"

Additional Checks: Design Bolted Connections of the splice plates to the girders, checking for shear, bearing, and slip critical connections.

26. CLOSURE POUR DESIGN: See sheet S2 for drawing of closure pour. Check the closure pour according to the negative bending capacity of the section. Use the minimum reinforcing properties for design, to be conservative.

Asteel 27.4in2

Art 1.4in2

Arb 1.9in2

cgsteel tslab ysteel 24.3in

cgrt

3in 1.5 5 in 8

Overall CG: Aneg Asteel Art Arb 30.7in2

3.9 in

Moment of Inertia: Izstl 3990in4

cgrb

tslab



1in



1.5

5 8

in

6.1 in

cgneg

Asteelcgsteel Artcgrt Arbcgrb Aneg

22.3 in

Ineg Izstl Asteel cgsteel cgneg 2 Art cgrt cgneg 2 Arb cgrb cgneg 2 5065.7in4

Section Moduli:

Stop_neg Sbot_neg

Ineg cgneg cgrt

276.4in3

Ineg

tslab ttf Dw tbf cgneg

276 in3

rneg

Ineg 12.8in Aneg

Concrete Properties: fc 5ksi Ec 4286.8ksi

Steel Properties:

Fy 50ksi Es 29000ksi

Lbneg 13.42ft

A-111

Negative Flexural Capacity:

Slenderness ratio for compressive flange: fneg

bbf 2tbf

8.5

Fyr 0.7Fy

Limiting ratio for compactness:

pfneg

0.38

Es Fy

9.2

Limiting ratio for noncompact Hybrid Factor:

rfneg

0.56

Es Fyr

16.1

Rh 1

35 ksi

Flange compression resistance:

Dcneg2

Dw 2

15.7 in

awc

2Dcneg2tw bbftbf

2.3

Rb

1.0 if 2 Dcneg2 d 5.7 Es

tw

Fy

min1.01

awc





2

Dcneg2



5.7

Es



otherwi



1200 300awc tw

Fy

Rb 1

Fnc1

RbRhFy if fneg d pfneg


1




1



Fyr RhFy





fneg rfneg

pfneg pfneg





Rb Rh Fy





otherwise

Fnc1 50ksi

Lateral Torsional Buckling Resistance:

rtneg

bbf

121




Dcneg2tw

3bbftbf



2.5 in

Lpneg

1.0rtneg

Es Fy

61.4 in

Lrneg

rtneg

Es Fyr

230.5in

Compressive Resistance:

Cb 1

Fnc2

RbRhFy if Lbneg d Lpneg


minCb1 1


Fyr RhFy





Lbneg Lpneg Lrneg Lpneg

Rb Rh Fy Rb Rh F

Fnc2 41.2ksi

Fnc min Fnc1Fnc2 41.2ksi

Tensile Flexural Resistance:

Fnt RhFy 50ksi

For Strength

A-112

Ultimate Moment Resistance:

Fnt_Serv 0.95RhFy 47.5ksi

For Service

Mn_neg min FntStop_negFncSbot_neg 946.7kipft

MUPier 948.1kipft

from external FE analysis

Check4 Mn_neg t MUPier 0
For additional design, one may calculate the force couple at the section over the pier to find the force in the UHPC closure joint. This force can be used to design any additional reinforcement used in the joint.

A-113

Summary of changes from SHRP2:
x Adapted the AASHTO LRFD Bridge Design Specifications, 6th Edition (2012) and GDOT Standards x MathCAD Design Aides provided in Appendix of the final report
- Design loadings calucation (moment, shear, and reaction) for girders - Design loadings calucation for deck x List of variable definitions added x Enhanced the descriptions for all design steps x Expansion of detail regarding girder sizing x New cross-section drawings x Load combination explanations x 12 ft travel lanes, 6 ft shoulders and 2% slope from crown to comply with GDOT standards
A-114

File Name: Steel Girder-40 ft.xmcd
CONCRETE DECKED STEEL GIRDER DESIGN FOR ABC
The following example details the design of a steel girder bridge accompanied by precast concrete deck panels. This particular example was created in accordance with Accelerated Bridge Construction (ABC) principles. The example shown here is presented for a Georgia Department of Transportation research endeavour into ABC technology, and is intended to simplify the design procedure of ABC style bridges. This example was taken from the SHRP 2 Manual (S2-R04-RR-2), and modified by a Georgia Southern University research team working for the Georgia Department of Transportation.
Note: These calculations do not consider every aspect of the bridge design process, and should not be condsidered exhaustive.
Note: All user inputs are highlighted in yellow for easy identification.
AASHTO LRFD Bridge Design Specifications (Sixth Edition with 2012 interims) was used to formulate this example. Located throughout this example are direct references to the AASHTO LRFD Bridge Design Specifications, which are found to the right side of their affiliated calculation.
Before beginning this example, a structural modeling program was used to analyze the superstructure. Although the calculations are not shown, the outputs are used for the design moments, shears and reactions in the example. BRIDGE GEOMETRY:

Design member parameters:

Deck Width: Roadway Width: Skew Angle:

wdeck 36ft 2in wroadway 33ft Skew 0deg

Deck Thickness Haunch Thickness Haunch Width Girder Spacing

td 10.5in th 2in wh 10.5in spacingint 2ft 11in spacingext 3ft

C. to C. Piers: C. to C. Bearings Bridge Length:

Length 40ft Lspan 37ft 10in Ltotal 3Length 120 ft

Stringer

W27x84

Stringer Weight

ws1 84plf

Stringer Length

Lstr Length 6in 39.5 ft

Average spacing of adjacent beams. This value is used so that effective deck width is not overestimated.

A-115

TABLE OF CONTENTS: General: 1. Introduction 2. Design Philosophy 3. Design Criteria 4. Material Properties 5. Load Combinations Girder Design: 6. Beam Section Properties 7. Permanent Loads 8. Precast Lifting Weight 9. Live Load Distribution Factors 10. Load Results 11. Flexural Strength 12. Flexural Strength Checks 13. Flexural Service Checks 14. Shear Strength 15. Fatigue Limit States 16. Bearing Stiffeners 17. Shear Connectors Deck Design: 18. Slab Properties 19. Permanent Loads 20. Live Loads 21. Load Results 22. Flexural Strength Capacity Check 23. Longitudinal Deck Reinforcing Design 24. Design Checks 25. Deck Overhang Design Continuity Design: 26. Compression Splice 27. Closure Pour Design
A-116

List of Variable Definitions
A = plan area of ice floe (ft2); depth of temperature gradient (in.) (C3.9.2.3) (3.12.3) AEP = apparent earth pressure for anchored walls (ksf) (3.4.1) AF = annual frequency of bridge element collapse (number/yr.) (C3.14.4) AS = peak seismic ground acceleration coefficient modified by short-period site factor (3.10.4.2) = notional slope of backfill (degrees) (3.11.5.8.1) B = equivalent footing width (ft) (3.11.6.3) Be = width of excavation (ft) (3.11.5.7.2b) BM = beam (width) for barge, barge tows, and ship vessels (ft) (C3.14.5.1) Bp = width of bridge pier (ft) (3.14.5.3) BR = vehicular braking force; base rate of vessel aberrancy (3.3.2) (3.14.5.2.3) b = braking force coefficient; width of a discrete vertical wall element (ft) (C3.6.4) (3.11.5.6) bf = width of applied load or footing (ft) (3.11.6.3) C = coefficient to compute centrifugal forces; constant for terrain conditions in relation to wind approach (3.6.3) (C3.8.1.1) CD = drag coefficient (s2 lbs./ft4) (3.7.3.1) CH = hydrodynamic mass coefficient (3.14.7) CL = lateral drag coefficient (C3.7.3.1) Csm = elastic seismic response coefficient for the mth mode of vibration (3.10.4.2) c = soil cohesion (ksf) (3.11.5.4) cf = distance from back of a wall face to the front of an applied load or footing (ft) (3.11.6.3) D = depth of embedment for a permanent nongravity cantilever wall with discrete vertical wall elements (ft) (3.11.5.6) DE = minimum depth of earth cover (ft) (3.6.2.2) Do = calculated embedment depth to provide equilibrium for nongravity cantilevered with continuous vertical elements by the simplified method (ft) (3.11.5.6) D1 = effective width of applied load at any depth (ft) (3.11.6.3) d = depth of potential base failure surface below base of excavation (ft); horizontal distance from the back of a wall face to the centerline of an applied load (ft) (3.11.5.7.2b) (3.11.6.3) dc = total thickness of cohesive soil layers in the top 100 ft (3.10.3.1) ds = total thickness of cohesionless soil layers in the top 100 ft (3.10.3.1) E = Young's modulus (ksf) (C3.9.5) EB = deformation energy (kip-ft) (C3.14.11) e = eccentricity of load on footing (ft) (3.11.6.3) F1 = lateral force due to earth pressure (kip/ft) (3.11.6.3) F2 = lateral force due to traffic surcharge (kip/ft) (3.11.6.3) f = constant applied in calculating the coefficient C used to compute centrifugal forces, taken equal to 4/3 for load combinations other than fatigue and 1.0 for fatigue (3.6.3) fc = specified compressive strength of concrete for use in design (ksi) (3.5.1) g = gravitational acceleration (ft/s2) (3.6.3) H = ultimate bridge element strength (kip); final height of retaining wall (ft); total excavation depth (ft); resistance of bridge component to a horizontal force (kip) (C3.11.1) (3.11.5.7.1) (3.14.5.4) Hp = ultimate bridge pier resistance (kip) (3.14.5.4) Hs = ultimate bridge superstructure resistance (kip) (3.14.5.4) H1 = distance from ground surface to uppermost ground anchor (ft) (3.11.5.7.1) Hn+1 = distance from base of excavation to lowermost ground anchor (ft) (3.11.5.7.1) h = notional height of earth pressure diagram (ft) (3.11.5.7) heq = equivalent height of soil for vehicular load (ft) (3.11.6.4) IM = dynamic load allowance (C3.6.1.2.5) k = coefficient of lateral earth pressure; number of cohesive soil layers in the top 100 ft (3.11.6.2) (3.10.3.1) ka = coefficient of active lateral earth pressure (3.11.5.1) ko = coefficient of at rest lateral earth pressure (3.11.5.1) kp = coefficient of passive lateral earth pressure (3.11.5.1) ks = coefficient of earth pressure due to surcharge (3.11.6.1) L = perimeter of pier (ft); length of soil reinforcing elements in an MSE wall (ft); length of footing (ft);
A-117

expansion length (in.) (3.9.5) (3.11.5.8) (3.11.6.3) (3.12.2.3) = characteristic length (ft); center-to-center spacing of vertical wall elements (ft) (C3.9.5) (3.11.5.6) m = multiple presence factor; number of cohesionless soil layers in the top 100 ft (3.6.1.1.2) (3.10.3.1) N = average Standard Penetration Test (SPT) blow count (blows/ft) (ASTM D1586) for the upper 100 ft of the soil profile (3.10.3.1)
Nch = average Standard Penetration Test (SPT) blow count (blows/ft) (ASTM D1586) for cohesive soil layers in the upper 100 ft of the soil profile and us for cohesive soil layers (PI > 20) in the top 100 ft ( us method) (3.10.3.1) Nchi = blowcount for a cohesionless soil layer (not to exceed 100 blows/ft in the above expression) (3.10.3.1) Ni = Standard Penetration Test blow count of a layer (not to exceed 100 blows/ft in the above expression). Note that when using Method B, N values are for cohesionless soils and cohesive soil and rock layers within the upper 100 ft Where refusal is met for a rock layer, Nishould be taken as 100 blows/ft (3.10.3.1) Ns = stability number (3.11.5.6) OCR = overconsolidation ratio (3.11.5.2) P = maximum vertical force for single ice wedge (kip); load resulting from vessel impact (kip); concentrated wheel load (kip); live load intensity; point load (kip) (C3.9.5) (3.14.5.4) (C3.6.1.2.5) (C3.11.6.2) (3.11.6.1) Pa = force resultant per unit width of wall (kip/ft) (3.11.5.8.1) PC = probability of bridge collapse (3.14.5) PD = design wind pressure (ksf) (3.8.1.2.1) PGA = peak seismic ground acceleration coefficient on rock (Site Class B) (3.10.2.1) (3.10.4.2) PH = lateral force due to superstructure or other concentrated lateral loads (kip/ft) (3.11.6.3) Ph = horizontal component of resultant earth pressure on wall (kip/ft) (3.11.5.5) PI = plasticity index (ASTM D4318) (3.10.3.1) Pp = passive earth pressure (kip/ft) (3.11.5.4) Pv = vertical component of resultant earth pressure on wall (kip/ft); load per linear foot of strip footing (kip/ft) (3.11.5.5) (3.11.6.3) Pv = load on isolated rectangular footing or point load (kip) (3.11.6.3) p = effective ice crushing strength (ksf); stream pressure (ksf); basic earth pressure (psf); fraction of truck traffic in a single lane; load intensity (ksf) (3.9.2.2) (3.7.3.1) (3.11.5.1) (3.6.1.4.2) (3.11.6.1) pa = apparent earth pressure (ksf); maximum ordinate of pressure diagram (ksf) (3.11.5.3) (3.11.5.7.1) pp = passive earth pressure (ksf) (3.11.5.4) Q = total factored load; load intensity for infinitely long line loading (kip/ft) (3.4.1) (3.11.6.2) Qi = force effects (3.4.1) q = surcharge pressure (ksf) (3.11.6.3) qs = uniform surcharge pressure (ksf) (3.11.6.1) R = radius of curvature (ft); radius of circular pier (ft); seismic response modification factor; reduction factor of lateral passive earth pressure; radial distance from point of load application to a point on the wall (ft); reaction force to be resisted by subgrade below base of excavation (kip/ft) (3.6.3) (3.9.5) (3.10.7.1) (3.11.5.4) (3.11.6.1) (3.11.5.7.1) Sm = shear strength of rock mass (ksf) (3.11.5.6) Su = undrained shear strength of cohesive soil (ksf) (3.11.5.6) Sub = undrained strength of soil below excavation base (ksf) (3.11.5.7.2b) Sv = vertical spacing of reinforcements (ft) (3.11.5.8.1) us = average undrained shear strength in ksf (ASTM D2166 or ASTM D2850) for the upper 100 ft of the soil profile (3.10.3.1) sui = undrained shear strength for a cohesive soil layer (not to exceed 5.0 ksf in the above expression) (3.10.3.1) S1 = horizontal response spectral acceleration coefficient at 1.0-s period on rock (Site Class B) (3.10.2.1) (3.10.4.2) T = mean daily air temperature (F) (C3.9.2.2) TF = period of fundamental mode of vibration of bridge (s) (3.10.2.2) Thi = horizontal load in anchor i (kip/ft) (3.11.5.7.1) Tm = period of vibration for mth mode (s) (3.10.4.2) Tmax = applied load to reinforcement in a mechanically stabilized earth wall (kip/ft) (3.11.5.8.2) TMaxDesign= maximum design temperature used for thermal movement effects (F) (3.12.2.1) (3.12.2.2) (3.12.2.3) TMinDesign = minimum design temperature used for thermal movement effects (F) (3.12.2.1) (3.12.2.2) (3.12.2.3) TS = corner period at which acceleration response spectrum changes from being independent of period to being inversely proportional to period (s) (3.10.4.2) T0 = reference period used to define shape of acceleration response spectrum (s) (3.10.4.2)
A-118

t = thickness of ice (ft); thickness of deck (in.) (3.9.2.2) (3.12.3) V = design velocity of water (ft/s); design impact speed of vessel (ft/s) (3.7.3.1) (3.14.6) VB = base wind velocity taken as 100 mph (3.8.1.1) VDZ = design wind velocity at design Elevation Z (mph) (3.8.1.1) VMIN = minimum design impact velocity taken not less than the yearly mean current velocity for the bridge location (ft/s) (3.14.6) V0 = friction velocity, a meteorological wind characteristic for various upwind surface characteristics (mph) (3.8.1.1) V30 = wind speed at 30.0 ft above low ground or water level (mph) (3.8.1.1) v = highway design speed (ft/s) (3.6.3) s v = average shear wave velocity for the upper 100 ft of the soil profile (3.10.3.1) W = displacement weight of vessel (tonne) (C3.14.5.1) w = width of clear roadway (ft); width of clear pedestrian and/or bicycle bridge (ft); width of pier at level of ice action (ft); specific weight of water (kcf); moisture content (ASTM D2216) (3.6.1.1.1) (3.6.1.6) (3.9.2.2) (C3.7.3.1) (3.10.3.1) X = horizontal distance from back of wall to point of load application (ft); distance to bridge element from the centerline of vessel transit path (ft) (3.11.6.2) (3.14.6) X1 = distance from the back of the wall to the start of the line load (ft) (3.11.6.2) X2 = length of the line load (ft) (3.11.6.2) Z = structure height above low ground or water level > 30.0 ft (ft); depth below surface of soil (ft); depth from the ground surface to a point on the wall under consideration (ft); vertical distance from point of load application to the elevation of a point on the wall under consideration (ft) (3.8.1.1) (3.11.6.3) (3.11.6.2) Z0 = friction length of upstream fetch, a meteorological wind characteristic (ft) (3.8.1.1) Z2 = depth where effective width intersects back of wall face (ft) (3.11.6.3) z = depth below surface of backfill (ft) (3.11.5.1) = constant for terrain conditions in relation to wind approach; coefficient for local ice condition; inclination of pier nose with respect to a vertical axis (degrees); inclination of back of wall with respect to a vertical axis (degrees); angle between foundation wall and a line connecting the point on the wall under consideration and a point on the bottom corner of the footing nearest to the wall (rad); coefficient of thermal expansion (in./in./F) (C3.8.1.1) (C3.9.2.2) (3.9.2.2) (C3.11.5.3) (3.11.6.2) (3.12.2.3) = safety index; nose angle in a horizontal plane used to calculate transverse ice forces (degrees); slope of backfill surface behind retaining wall; {+ for slope up from wall; for slope down from wall} (degrees) (C3.4.1) (3.9.2.4.1) (3.11.5.3)
= slope of ground surface in front of wall {+ for slope up from wall; for slope down from wall} (degrees) (3.11.5.6) = load factors; unit weight of materials (kcf); unit weight of water (kcf); unit weight of soil (kcf) (C3.4.1) (3.5.1) (C3.9.5) (3.11.5.1) s = unit weight of soil (kcf) (3.11.5.1) s = effective soil unit weight (kcf) (3.11.5.6) EQ = load factor for live load applied simultaneously with seismic loads (3.4.1) eq = equivalent-fluid unit weight of soil (kcf) (3.11.5.5) i = load factor (3.4.1) p = load factor for permanent loading (3.4.1) SE = load factor for settlement (3.4.1) TG = load factor for temperature gradient (3.4.1) = movement of top of wall required to reach minimum active or maximum passive pressure by tilting or lateral translation (ft) (C3.11.1) (3.11.5.5) p = constant horizontal earth pressure due to uniform surcharge (ksf) (3.11.6.1) ph = constant horizontal pressure distribution on wall resulting from various types of surcharge loading (ksf) (3.11.6.2) T = design thermal movement range (in.) (3.12.2.3) iH = horizontal stress due to surcharge load (ksf) (3.11.6.3) iv = vertical stress due to surcharge load (ksf) (3.11.6.3) = angle of truncated ice wedge (degrees); friction angle between fill and wall (degrees); angle between foundation wall and a line connecting the point on the wall under consideration and a point on the bottom corner of the footing furthest from the wall (rad) (C3.9.5) (3.11.5.3) (3.11.6.2) i = load modifier specified in Article 1.3.2; wall face batter (3.4.1) (3.11.5.9)
A-119

= angle of back of wall to the horizontal (degrees); angle of channel turn or bend (degrees); angle between direction of stream flow and the longitudinal axis of pier (degrees) (3.11.5.3) (3.14.5.2.3) (3.7.3.2) f = friction angle between ice floe and pier (degrees) (3.9.2.4.1) i = standard deviation of normal distribution (3.14.5.3) iT = tensile strength of ice (ksf) (C3.9.5) = Poisson's Ratio (dim.) (3.11.6.2) = resistance factors (C3.4.1) f = angle of internal friction (degrees) (3.11.5.4)
f = effective angle of internal friction (degrees) (3.11.5.2) r = internal friction angle of reinforced fill (degrees) (3.11.6.3) s = angle of internal friction of retained soil (degrees) (3.11.5.6)

Permanent Loads CR = force effects due to creep DD = downdrag force DC = dead load of structural components and nonstructural attachments DW = dead load of wearing surfaces and utilities EH = horizontal earth pressure load EL = miscellaneous locked-in force effects resulting from the construction process, including jacking apart of cantilevers in segmental construction ES = earth surcharge load EV = vertical pressure from dead load of earth fill

Transient Loads
EQ = earthquake load FR = friction load IC = ice load IM = vehicular dynamic load allowance LL = vehicular live load LS = live load surcharge PL = pedestrian live load SE = force effect due to settlement TG = force effect due to temperature gradient TU = force effect due to uniform temperature WA = water load and stream pressure WL = wind on live load WS = wind load on structure

1. INTRODUCTION
AASHTO LRFD principles were used in the design of this superstructure. The example is designed for a bridge with three even spans, and has no skew. The bridge has two 12-foot wide lanes and two 6-foot wide shoulders, for a total roadway width of 36' from curb to curb. The bridge deck is precast reinforced concrete with overhangs at the outermost girders. The longitudinal girders are placed as simply supported modules, and made continuous with connection plates and cast-in-place deck joints. The design of the continuity at the deck joint is addressed in final sections of this example.

The cross-section consists of six modules. The interior modules are identical and consist of two steel girders and a 6'-0" precast composite deck slab. Exterior modules include two steel girders and a 6'-1" precast composite deck slab, with F-shape barriers. Grade 50 steel is used throughout, and the deck concrete has a compressive strength of 5,000 psi.
A-120

The closure pour joints between the modules use Ultra High Performance Concrete with a strength of 21,000 psi.
Steel girder design steps, including constructability checks, fatigue design for infinite fatigue lift (unless otherwise noted), and bearing stiffener design comprise the majority of the example. Diaphragm and deck design procedures are present, but not detailed.

Tips for reading this Design Example:

This calculation was prepared with Mathcad version 14. Mathcad was used in this instance to provide a clear representation of formulas, and their execution. Design software other than Mathcad is recommended for a speedier and more accurate design.

Mathcad is not a design software. Mathcad executes user mathematical and simple logic commands.

Example 1: User inputs are noted with dark shaded boxes. Shading of boxes allows the user to easily find the location of a desired variable. Given that equations are written in mathcad in the same fashion as they are on paper, except that they are interactive, shading input cells allows the user to quicly locate inputs amongst other data on screen. Units are user inputs.

Height of Structure:

Hstructure 25ft

Example 2: Equations are typed directly into the workspace. Mathcad then reads the operators and executes the calculations.

Panels are 2.5'

Npanels

Hstructure 2.5ft

Npanels 10

Example 3: If Statements are an important operator that allow for the user to dictate a future value with given parameters. They are marked by a solid bar and operate with the use of program specific logic commands.

Operator offers discount per volume of panels

Discount

.75 if Npanels t 6 .55 if Npanels t 10

Discount 0.6

1 otherwise
Example 4: True or False Verification Statements are an important operator that allow for the user to verify a system criteria that has been manually input. They are marked by lighter shading to make a distinction between the user inputs. True or false statements check a single or pairs of variables and return a Zero or One.

Owner to proceed if discounts on retail below 60%

Discount d .55 1

2. DESIGN PHILOSOPHY

The superstructure of the bridge in this example consists of modules, which are two rolled steel girders supporting a bridge deck panel along their length. The girders are assumed to be simply supported under the weight of the deck panels. In each module, one girder is assumed to support half the weight of its respective deck panel.

The barrier wall is added to exterior modules once the deck and girders are joined. When working with the barrier dead load, the weight is assumed to be evenly distributed between the two modules. Under the additional barrier dead load, the girders are again assumed to be simply supported.

Concerning transportation of modules, it is assumed that the deck has reached 28-day concrete strength, and the deck is fully composite with the girders. The self-weight of the module during lifting and placement is assumed as evenly distributed to four pick points (two per girder).

The modules are placed such that there is a bearing on each end and are again simply supported. The continuous span

A-121

configuration, which includes two bearings per pier on either side of the UHPC joints, is analyzed for positive and negative bending and shear (using simple or refined methods). The negative bending moment above the pier is used to find the force couple for continuity design, between the compression plates at the bottom of the girders and the closure joint in the deck.
The deck design utilizes the equivalent strip method.

3. DESIGN CRITERIA
The first step for any bridge design is to establish the design criteria. The following is a summary of the primary design criteria for this design example:

Governing Specifications: AASTHO LRFD Bridge Design Specifications (6th Edition with 2012 interims)

Design Methodology:

Load and Resistance Factor Design (LRFD)

Live Load Requirements: HL-93

S S3.6

Section Constraints:

Wmod.max 200kip Upper limit on the weight of the modules, based on common lifting and transport capabilities without significantly increasing time and/or cost due to unconventional equipment or permits

4. MATERIAL PROPERTIES Structural Steel Yield Strength: Structural Steel Tensile Strength: Concrete 28-day Compressive Strength: Reinforcement Strength: Steel Density: Concrete Density: Modulus of Elasticity - Steel: Modulus of Elasticity - Concrete:
Modular Ratio:
Future Wearing Surface Density: Future Wearing Surface Thickness:

Fy 50ksi

Fu 65ksi

fc 5ksi

fc_uhpc 21ksi

Fs 60ksi

ws 490pcf

wc 150pcf

Es 29000ksi

Ec

33000

wc



1.5

1000pcf

fcksi

n

Es ceil

7

Ec

4286.8 ksi

Wfws 140pcf tfws 2.5in

(Assumed)

STable 6.4.1-1 STable 6.4.1-1 S5.4.2.1 S5.4.3 & S6.10.3.7 STable 3.5.1-1 STable 3.5.1-1
STable 3.5.1-1

5. LOAD COMBINATIONS

A-122

The following load combinations will be used in this design example, in accordance with Table 3.4.1-1.

Strength I--Basic load combination relating to the normal vehicular use of the bridge without wind.

Strength III--Load combination relating to the bridge exposed to wind velocity exceeding 55 mph.

Strength V--Load combination relating to normal vehicular use of the bridge with wind of 55 mph velocity.

Service I--Load combination relating to the normal operational use of the bridge with a 55 mph wind and all loads taken at their nominal values. Also related to deflection control in buried metal structures, tunnel liner plate, and thermoplastic pipe, to control crack width in reinforced concrete structures, and for transverse analysis relating to tension in concrete segmental girders. This load combination should also be used for the investigation of slope stability.

Service II--Load combination intended to control yielding of steel structures and slip of slip-critical connections due to vehicular live load.
Fatigue I--Fatigue and fracture load combination related to infinite load-induced fatigue life.

Strength I = 1.25DC + 1.5DW + 1.75(LL+IM), where IM = 33% Strength III = 1.25DC + 1.5DW + 1.40WS Strength V = 1.25DC + 1.5DW + 1.35(LL+IM) + 0.40WS + 1.0WL, where IM = 33% Service I = 1.0DC + 1.0DW + 1.0(LL+IM) + 0.3WS + 1.0WL, where IM = 33% Service II = 1.0DC + 1.0DW + 1.3(LL+IM), where IM = 33% Fatigue I = 1.5(LL+IM), where IM = 15%

6. BEAM SECTION
Determining the proper girder depth and dimensions is a vital part of any bridge design process. The size of the girder is a major factor in the cost of the bridge. From Table 2.5.2.6.3-1, the suggested minimum overall depth of the composite I-section in a continuous span is equal to 0.032L.
Thus we have, (.032*40ft) = 1.28' = 15.36" (this is a minimum and can be adjusted to meet criteria)
The following girder dimensions were taken from the AISC Steel Construction Manual (14th Edition).

Determine Beam Section Properties:

Girder

W27x84

btfx ttf

A-123

Top Flange Bottom Flange Web Girder Depth

btf 10.0in bbf 10.0in Dw 25.4in dgird 26.7in

ttf 0.64in tbf 0.64in tw 0.46in

Dw x tw bbfx tbf

Check Flange Proportion Requeirements Met:

btf d 12.0 1 2ttf

btf

t

Dw 6

1

ttf t 1.1tw 1 tbf 3 bbf

0.1 d 12 d 10 1 ttf 3 btf

12

bbf d 12.0 1 2tbf

bbf

t

Dw 6

1

tbf t 1.1tw 1

tbf bbf

12 t 0.3 1 ttf btf

12

Properties for use when analyzing under beam self weight (steel only):

S 6.10.2.2

Atf btfttf

Abf bbftbf

Asteel Abf Atf Aw

Aw Dwtw Asteel 24.5in2

ysteel

Atf



ttf 2



Abf





tbf 2



Dw

ttf



Aw



Dw 2



ttf

Asteel

ysteel 13.3in

Total steel area. Steel centroid from top.

Calculate Iz:

Moment of inertia about Z axis.

Izsteel

twDw3 12



btf ttf 3 12



bbftbf3 12



Aw



Dw 2



ttf



ysteel2

Atf





ysteel



ttf 2 2

Abf





Dw



tbf 2



ttf



y steel 2

Calculate Iy:

Iysteel

Dwtw3 ttfbtf3 tbfbbf3 12

Moment of inertia about Y axis.

Calculate Ix:

Ixsteel

1 3





btf



ttf

3



bbftbf3



Dwtw3

Izsteel 2798.469in4

Iysteel

106.873 in4

Moment of inertia about X axis.

Ixsteel 2.6in4

Asteel 24.5in2

A-124

Composite Section Properties (Uncracked Section - used for barrier dead load and live load positive bending): Determine composite slab and reinforcing properties

Slab thickness assumes some sacrificial thickness; use:
Dt tslab ttf Dw tbf 34.7in

tslab 8in Total section depth

beff spacingint beff 35in

Effective width.

S 4.6.2.6.1 LRFD

btr

beff n

Transformed slab width as steel.

Izslab

btr

tslab3 12

Transformed slab moment of inertia about z axis as steel.

Aslab btrtslab

Transformed slab area as steel.

Slab reinforcement: (Use #5 @ 8" top, and #6 @ 8" bottom; additional bar for continuous segments of #6 @ 12")

Typical Cross Section

Art

0.465

in2 ft



beff

1.4 in2

Cross Section Over Support

Arb

0.66

in2 ft



beff

1.9 in2

Artadd

0.44

in2 ft



beff

1.3 in2

A-125

Ar Art Arb 3.3in2

crt

2.5in



0.625in





5 16

in

cr

Artcrt Arbcrb Ar

4.9 in

3.4 in

Arneg Ar Artadd 4.6in2

crb

tslab



1.75in





6 16



in

5.9 in

ref from top of slab

crneg

Artcrt Arbcrb Artaddcrt
Arneg

4.5 in

Find composite section centroid:

Ax

Asteel

Ar(n n

1)

Aslab

yslab

tslab 2

yst

Atf





ttf 2



tslab



Abf





tbf 2



Dw

ttf



tslab



Aw



Dw 2



ttf



tslab

Asteel

yc

ystAsteel

crAr(n 1) n

Aslabyslab

Ax

yc 10.3in

Calculate Transformed Iz for composite section:

Iz

Izsteel



Asteel

yst



yc

2

Izslab



Aslab

yslab

yc

2

Ar(n n

1)

cr

yc

2

Calculate Transformed Iy for composite section:

ttr

tslab n

Iyslab

ttr b eff 3 12

Transformed slab thickness. Transformed moment of inertia about y axis of slab.

Iy Iysteel Iyslab

Transformed moment of inertia about the y axis (ignoring reinforcement).

Centroid of steel from top of slab.
Centroid of transformed composite section from top of slab.
Transformed moment of inertia about the z axis.

Calculate Transformed Ix for composite section:

Ix

1 3





btf



ttf

3



bbftbf3



Dwtw3



btrtslab3

Transformed moment of inertia about the x axis.

Results: Ax 67.3in2 Iy 4190.2in4

Iz 7666.4in4 Ix 855.9in4

Composite Section Properties (Uncracked Section - used for live load negative bending):

Find composite section area and centroid:

Axneg

Asteel

Arneg(n n

1)



Aslab

ycneg

ysteelAsteel

crnegArneg(n n

1)



Aslabyslab

Axneg

ycneg 7.4in

Centroid of transformed composite section from top of slab.

A-126

Calculate Transformed Izneg for composite negative moment section:

Izneg

Izsteel

Asteel

ysteel

ycneg

2

Izslab

Aslab

yslab

ycneg

2

Arneg(n n

1)

crneg

ycneg

2

Transformed moment of inertia about the z

axis.

Izneg 4371.7in4

Composite Section Properties (Cracked Section - used for live load negative bending):

Find cracked section area and centroid:

Acr ycr

Asteel Arneg 29in2
Asteelysteel Arnegcrneg
Acr

11.9 in

ycrb

Find cracked section moments of inertia and section moduli:

Izcr Izsteel Asteel ysteel ycr 2 Ar cr ycr 2

Izcr

tslab ttf Dw tbf ycr 3010.5 in4

Iycr Iysteel

Ixcr

1 3





btf



ttf

3



b bf ttf 3



Dwtw3

dtopcr ycr crt

Iycr 106.9in4 Ixcr 2.6in4 dtopcr 8.5in

22.7 in

dbotcr Stopcr

tslab ttf Dw tbf ycr Izcr dtopcr

Sbotcr

Izcr dbotcr

dbotcr Stopcr

22.7 in 353.8in3

Sbotcr 132.4in3

7. PERMANENT LOADS

Phase 1: Steel girders are simply supported, and support their self-weight plus the weight of the slab. Steel girders in each module for this example are separated by three diaphragms - one at each bearing location, and one at midspan. Other module span configurations may require an increase or decrease in the number of diaphragms.

Wdeck_int wcspacinginttd

Wdeck_int 382.8plf

Wdeck_ext wcspacingexttd

Wdeck_ext 393.8plf

Whaunch wcwhth

Whaunch 21.9plf

Wstringer ws1

Wstringer 84plf

Diaphragms: Diaphragm Weight

MC18x42.7 ws2 42.7plf

Thickness Conn. Plate Width Conn. Plate

tconn

5 in
8

wconn 5in

Diaphragm Length

Wdiaphragm

ws2

Ldiaph 2

Ldiaph 4ft 2.5in

Height Conn. Plate

hconn 28.5in

Wdiaphragm 89.8lbf

A-127

Wconn 2wstconnwconnhconn
WDCpoint Wdiaphragm Wconn 1.05
Equivalent distributed load from DC point loads:

Wconn 50.5lbf

WDCpoint 147.4lbf

wDCpt_equiv

3WDCpoint Lstr

11.2 plf

Interior Uniform Dead Load, Phase 1: Exterior Uniform Dead Load, Phase 1:

WDCuniform1_int Wdeck_int Whaunch Wstringer wDCpt_equiv WDCuniform1_ext Wdeck_ext Whaunch Wstringer wDCpt_equiv

499.9plf 510.8plf

Moments due to Phase 1 DL: Shear due to Phase 1 DL:

MDC1_int(x)

WDCuniform1_intx 2

Lstr



x

VDC1_int(x)

WDCuniform1_int



Lstr 2



x

MDC1_ext(x)

WDCuniform1_extx 2

Lstr



x

VDC1_ext(x)

WDCuniform1_ext



Lstr 2



x

Phase 2: Steel girders are simply supported and composite with the deck slab, and support their self-weight plus the weight of the slab in addition to barriers on exterior modules. Barriers are assumed to be evenly distributed between the two exterior module girders.

Barrier Area

Abarrier 2.89ft2

Barrier Weight

Wbarrier

wcAbarrier 2

Wbarrier 216.8plf

Interior Dead Load, Phase 2:

WDCuniform_int WDCuniform1_int 499.9plf

Exterior Dead Load, Phase 2: WDCuniform_ext WDCuniform1_ext Wbarrier 727.6plf

Moments due to Phase 2 DL: Shear due to Phase 2 DL:

MDC2_int(x)

WDCuniform_intx 2

Lstr



x

VDC2_int(x)

WDCuniform_int



Lstr 2



x

MDC2_ext(x)

WDCuniform_extx 2

Lstr



x

VDC2_ext(x)

WDCuniform_ext



Lstr 2



x

Phase 3: Girders are composite and have been made continuous. Utilities and future wearing surface are applied.

Unit Weight Overlay

wws 30psf

Wws_int wwsspacingint
Wws_ext wws spacingext 1ft 7in

Wws_int 87.5plf Wws_ext 42.5plf

Unit Weight Utilities

Wu 15plf

WDWuniform_int Wws_int Wu WDWuniform_ext Wws_ext Wu Moments due to DW:
Shears due to DW:

WDWuniform_int 102.5plf

WDWuniform_ext 57.5plf

MDW_int(x)

WDWuniform_intx 2

Lstr



x

MDW_ext(x)

WDWuniform_extx 2

Lstr



x

VDW_int(x)

WDWuniform_int





Lstr 2



x

VDW_ext(x)

WDWuniform_ext



Lstr 2



x

A-128

8. PRECAST LIFTING WEIGHTS AND FORCES

This section addresses the construction loads for lifting the module into place. The module is lifted from four points, at some distance, Dlift from each end of each girder.

Distance from end of lifting point:

Dlift 8.75ft

Assume weight uniformly distributed along girder, with 30% Dynamic Dead Load Allowance:

Dynamic Dead Load Allowance:

DLIM 30%

Interior Module: Total Interior Module Weight: Vertical force at lifting point: Equivalent distributed load:
Min (Neg.) Moment during lifting:
Max (Pos.) Moment during lifting:

Wint LstrWDCuniform_int 3WDCpoint 2(1 DLIM) 52.5kip

Flift_int

Wint 4

13.1 kip

wint_IM

Wint 2Lstr

664.4plf

Mlift_neg_max_int

wint_IM



Dlift2
2

Mlift_neg_max_int 25.4kipft

Mlift_pos_max_int

0

if

wint_IM

Lstr 8

2Dlift

2



Mlift_neg_max_int



0

wint_IM

Lstr 8

2Dlift

2



Mlift_neg_max_int

Mlift_pos_max_int 14.8kipft

Exterior Module: Total Exterior Module Weight: Vertical force at lifting point: Equivalent distributed load:
Min (Neg.) Moment during lifting:

Wext LstrWDCuniform_ext 3WDCpoint WbarrierLstr 2(1 DLIM) 98.1kip

Flift_ext

Wext 4

24.5 kip

wext_IM

Wext 2Lstr

Mlift_neg_max_ext

1242.2 plf

wext_IM



Dlift2 2

Mlift_neg_max_ext 47.6kipft

A-129

Max (Pos.) Moment during lifting: Mlift_pos_max_ext

0

if

wext_IM

Lstr 8

2Dlift

2



Mlift_neg_max_ext



0

wext_IM

Lstr 8



2Dlift

2



Mlift_neg_max_ext

Max Shear during lifting:

Mlift_pos_max_ext 27.6kipft
Vlift max wext_IMDlift Flift_ext wext_IMDlift

13.7 kip

9. LIVE LOAD DISTRIBUTION FACTORS

These factors represent the distribution of live load from the deck to the girders in accordance with AASHTO Section 4, and assumes the deck is fully continuous across the joints.
Girder Section Modulus: Izsteel 2798.5in4

Girder Area:
Girder Depth:
Distance between centroid of deck and centroid of beam: Modular Ratio:

Asteel 24.5in2 dgird 26.7in

eg

td 2



th

dgird 2

n7

20.6 in

Multiple Presence Factors:

MP1 1.2

MP2 1.0

S3.6.1.1.2-1

Interior Stringers for Moment:
One Lane Loaded: Kg nIzsteel Asteeleg2

92319.5 in4

S4.6.2.2.1-1

Two Lanes Loaded: Governing Factor:

gint_1m

0.06





spacingint 14ft



0.4



spacingint



0.3



Lspan

Kg



0.1

Lspantd3



0.268

gint_2m

0.075





spacingint 9.5ft



0.6



spacingint



0.2



Lspan

Kg 0.1

Lspantd3



0.323

gint_m max gint_1mgint_2m 0.323

Interior Stringers for Shear: One Lane Loaded: gint_1v
Two Lanes Loaded: gint_2v

0.36 spacingint 0.477



25ft

0.2

spacingint





spacingint



2



12ft

35ft

Governing Factor: gint_v max gint_1v gint_2v 0.477
Exterior Stringers for Moment:

0.436

A-130

One Lane Loaded: Use Lever Rule. Wheel is 2' from barrier; barrier is 2" beyond exterior stringer. de 2in

Lspa 4.5ft r Lspa de 2ft 2.7ft

Two Lanes Loaded:

gext_1m

MP1

0.5r Lspa

e2m

0.77 de 9.1ft

0.356 0.7883

Governing Factor:

gext_2m e2mgint_2m 0.254
gext_m max gext_1mgext_2m

0.356

Exterior Stringers for Shear: One Lane Loaded: Use Lever Rule. gext_1v gext_1m

0.356

Two Lanes Loaded:

e2v

0.6 de 10ft

0.62

gext_2v e2vgint_2v 0.269

Governing Factor: gext_v max gext_1vgext_2v 0.356

FACTOR TO USE FOR SHEAR: gv max gint_v gext_v 0.477

FACTOR TO USE FOR MOMENT: gm max gint_mgext_m 0.356

10. LOAD RESULTS

Case 1: Dead Load on Steel Only (calculated in Section 7). Negative moments are zero and are not considered. Because the girder is simply supported, the maximum moment is at x = Lstr/2 and the maximum shear is at x = 0.

Interior Girder

MDC1int

MDC1_int



Lstr 2



97.5kipft

MDW1int 0kipft MLL1int 0kipft

Exterior Girder

VDC1int VDC1_int(0) 9.9kip

MDC1ext

MDC1_ext

Lstr 2



99.6kipft

VDW1int 0kip MDW1ext 0kipft

VLL1int 0kip MLL1ext 0kipft

Load Cases:

VDC1ext VDC1_ext(0) 10.1kip

VDW1ext 0kip

VLL1ext 0kipft

M1_STR_I max 1.25MDC1int 1.5MDW1int 1.75MLL1int1.25MDC1ext 1.5MDW1ext 1.75MLL1ext 124.5kipf V1_STR_I max 1.25VDC1int 1.5VDW1int 1.75VLL1int1.25VDC1ext 1.5VDW1ext 1.75VLL1ext 12.6kip

Case 2: Dead Load on Composite Section (calculated in Section 7). Negative moments are zero and are not considered. Again, the maximum moment occur at x = Lstr/2 and the maximum shear is at x = 0.

Interior Girder

MDC2int

MDC2_int



Lstr 2



97.5kipft

MDW2int 0kipft

MLL2int 0kipft

VDC2int VDC2_int(0) 9.9kip

VDW2int 0kip

VLL2int 0kip

Exterior Girder

MDC2ext

MDC2_ext

Lstr 2



141.9kipft

MDW2ext 0kipft

MLL2ext 0kipft

VDC2ext VDC2_ext(0) 14.4kip

VDW2ext 0kip

VLL2ext 0kip

Load Cases:
M2_STR_I max 1.25MDC2int 1.5MDW2int 1.75MLL2int1.25MDC2ext 1.5MDW2ext 1.75MLL2ext 177.4kipf

A-131

V2_STR_I max 1.25VDC2int 1.5VDW2int 1.75VLL2int 1.25VDC2ext 1.5VDW2ext 1.75VLL2ext 18kip

Case 3: Composite girders are lifted into place from lifting points located distance Dlift from the girder edges. Maximum moments and shears were calculated in Section 8.

Interior Girder MDC3int Mlift_pos_max_int 14.8kipft

MDW3int 0kipft

MLL3int 0kipft

MDC3int_neg Mlift_neg_max_int 25.4kipft MDW3int_neg 0kipft MLL3int_neg 0kipft

VDC3int Vlift 13.7kip

VDW3int 0kip

VLL3int 0kip

Exterior Girder MDC3ext Mlift_pos_max_ext 27.6kipft

MDW3ext 0kipft

MLL3ext 0kipft

MDC3ext_neg Mlift_neg_max_ext 47.6kipft MDW3ext_neg 0kipft MLL3ext_neg 0kipft

VDC3ext Vlift 13.7kip

VDW3ext 0kip

VLL3ext 0kip

Load Cases:
M3_STR_I max 1.5MDC3int 1.5MDW3int1.5MDC3ext 1.5MDW3ext 41.4kipft
M3_STR_I_neg max 1.5MDC3int_neg 1.5MDW3int_neg 1.5MDC3ext_neg 1.5MDW3ext_neg
V3_STR_I max 1.5VDC3int 1.5VDW3int1.5VDC3ext 1.5VDW3ext 20.5kip

71.3kipft

Case 4: Composite girders made continuous. Utilities and future wearing surface are applied, and live load. Maximum

moment and shear results are from a finite element analysis not included in this design example. The live load value

includes the lane fraction calculated in Section 9, and impact.

Governing Loads: MDC4 93.4kipft

MDW4 13.1kipft

MLL4 201.6kipft

MWS4 0kipft

MW4 0kipft

MDC4neg 116.8kipft MDW4neg 16.4kipft MLL4neg 134.7kipft

MWS4neg 0kipft

MWL4neg 0kipft

VDC 17.5kip

VDW 2.5kip

VLL 87.6kip

Vu 1.25VDC 1.5VDW 1.75VLLgv 98.7kip

Load Cases: M4_STR_I 1.25MDC4 1.5MDW4 1.75MLL4 489.2kipft
M4_STR_I_neg 1.25MDC4neg 1.5MDW4neg 1.75MLL4neg 406.3kipft

M4_STR_III 1.25MDC4 1.5MDW4 1.4MWS4 136.4kipft M4_STR_III_neg 1.25MDC4neg 1.5MDW4neg 1.4MWS4 170.6kipft

M4_STR_V 1.25MDC4 1.5MDW4 1.35MLL4 0.4MWS4 1.0MW4 408.6kipft M4_STR_V_neg 1.25MDC4neg 1.5MDW4neg 1.35MLL4neg 0.4MWS4neg 1.0MWL4neg 352.4kipft

M4_SRV_I 1.0MDC4 1.0MDW4 1.0MLL4 0.3MWS4 1.0MW4 308.1kipft M4_SRV_I_neg 1.0MDC4neg 1.0MDW4neg 1.0MLL4neg 0.3MWS4neg 1.0MWL4neg M4_SRV_II 1.0MDC4 1.0MDW4 1.3MLL4 368.6kipft M4_SRV_II_neg 1.0MDC4neg 1.0MDW4neg 1.3MLL4neg 308.3kipft

267.9kipft

A-132

11. FLEXURAL STRENGTH
The flexural resistance shall be determined as specified in LRFD Design Article 6.10.6.2. Determine Stringer Plastic Moment Capacity First.

LFRD Appendix D6 Plastic Moment

Find location of PNA:

Forces:

Prt ArtFs 81.4kip Prb ArbFs 115.5kip

Ps 0.85fcbefftslab 1190kip Pc Fybtfttf 320kip

Pw FyDwtw 584.2kip Pt Fybbftbf 320kip

A-133

PNApos

"case 1" if Pt Pw t Pc Ps Prt Prb

otherwise
"case 2" if Pt Pw Pc t Ps Prt Prb

otherwise

"case 3"

if Pt Pw Pc


t



crb tslab



Ps



Prt



Prb


otherwise

"case 4"

if Pt Pw Pc Prb


t



crb tslab



Ps



Prt


otherwise

"case 5"

if Pt Pw Pc Prb


t



crt tslab



Ps



Prt


otherwise

"case 6"

if

Pt Pw Pc Prb Prt

t



crt tslab

Ps


"case 7"

if

Pt Pw Pc Prb Prt

d



crt tslab

Ps


otherwise

PNAneg

PNApos "case 3"
"case 1" if Pc Pw t Pt Prt Prb "case 2" if Pt Pw Pc t Prt Prb otherwise

PNAneg "case 1"

Calculate Y, Dp, and Mp:

D Dw

ts tslab

Case I : Plastic Nuetral Axis in the Steel Web

Y1

D





Pt



Pc



Ps



Prt



Prb



1

2

Pw



th 0

Crt crt Crb crb

DP1 ts th ttf Y1

MP1

Pw
2D

Y12



D



Y1

2



PsPcY1Y1

ts 2



ttf



th



Prt

ts



Crt



ttf 2



Pt



D



Y1

tbf 2



ttf



Y1



th

Prb ts Crb ttf Y1 th



Y1neg



D 2



1



Pc

Pt

Prt Pw

Prb


Dp1neg ts th ttf Y1neg

DCP1neg



D 2Pw





Pt



Pw



Prb



Prt



Pc

A-134

Mp1neg




Pw 2D

Pt



D

Y1neg2
Y1neg



Dw Y1neg 2 Prt ts Crt ttf Y1neg th

tbf 2



Pc



Y1neg



ttf 2

Prb ts Crb ttf Y1neg th




Case II: Plastic Nuetral Axis in the Steel Top Flange

Y2

ttf





Pw



Pt



Ps



Prt



Prb



1

2

Pc



DP2 ts th Y2

MP2

Pc
2ttf

Y22



ttf



Y2

2



Ps



Y2





Pw



D 2

ts 2 ttf

th Prt ts Crt th Y2



Y2



Pt



D



Y2

tbf 2



Prb
ttf

ts



Crb



th



Y2




Y2neg



ttf 2

1



Pw Pc Prt Prb



Pt



DP2neg ts th Y2neg

DCP2neg D

Mp2neg




Pt 2ttf





Y2neg

2





ttf



Y2neg

2



PrPtwtsttf

Crt

th Y2neg

Y2neg



D 2





Prb

Pc



ts Crb ts th

th Y2neg

Y2neg

ttf 2





Case III: Plastic Nuetral Axis in the Concrete Deck Below the Bottom Reinforcing

Y3

ts


Pc



Pw



Pt Ps



Prt



Prb

DP3 Y3

MP3

Ps
2ts





Y32



Prt Y3 Crt



Pt



D



tbf 2

Prb Crb Y3 ttf ts th



Pc



ttf 2

Y3



ts



th

Y3



Pw



D 2



ttf



th

ts



Y3




Case IV: Plastic Nuetral Axis in the Concrete Deck in the bottom reinforcing layer

Y4 Crb

DP4 Y4

MP4

Ps
2ts





Y42



Prt Y4 Crt



Pt



D



tbf 2



Pc



ttf 2

ttf th



th ts

ts
Y4

Y4



Pw



D 2



ttf



th



ts



Y4




Case V: Plastic Nuetral Axis in the Concrete Deck between top and bot reinforcing layers

Y5

ts


Prb



Pc



Pw Ps



Pt



Prt

DP5 Y5

MP5

Ps
2ts





Y52



Prt Y5 Crt



Pt



D



tbf 2

Prb ts Crb
ttf ts th

Y5 Y5



Pc



ttf 2



ts



th

Y5



Pw



D 2



ttf



th

ts



Y5




A-135

Ypos

Y1 if PNApos = "case 1" Y2 if PNApos = "case 2" Y3 if PNApos = "case 3" Y4 if PNApos = "case 4" Y5 if PNApos = "case 5"

DPpos

DP1 if PNApos = "case 1" DP2 if PNApos = "case 2" DP3 if PNApos = "case 3" DP4 if PNApos = "case 4" DP5 if PNApos = "case 5"

MPpos

MP1 if PNApos = "case 1" MP2 if PNApos = "case 2" MP3 if PNApos = "case 3" MP4 if PNApos = "case 4" MP5 if PNApos = "case 5"

Ypos 6.9in

DPpos 6.9in

MPpos 1781.7kipft

Dp = distance from the top of slab of composite section to the neutral axis at the plastic moment (neglect positive moment reinforcement in the slab).

Yneg

Y1neg if PNAneg = "case 1" Y2neg if PNAneg = "case 2"

DPneg

Dp1neg if PNAneg = "case 1" DP2neg if PNAneg = "case 2"

MPneg

Mp1neg if PNAneg = "case 1" Mp2neg if PNAneg = "case 2"

Yneg 8.4in

DPneg 17.1in

MPneg 14864.2kipin

Depth of web in compression at the plastic moment [D6.3.2]:

At bbftbf

Ac btfttf

Dcppos

D FyAt
2



FyAc

0.85fcAslab FyAw



FsAr



1

Dcppos

(0in) if PNApos z "case 1"
(0in) if Dcppos 0
Dcppos if PNApos = "case 1"

Dcppos 0in

Dcpneg

DCP1neg if PNAneg = "case 1" DCP2neg if PNAneg = "case 2"

Dcpneg 17in

Positive Flexural Compression Check:

From LRFD Article 6.10.2

Check for compactness:

Web Proportions: Dw d 150 1 tw

Web slenderness Limit:

2 Dcppos d 3.76 Es 1

tw

Fy

S 6.10.6.2.2

Therefore Section is considered compact and shall satisfy the requirements of Article 6.10.7.1.

Mn MPpos if DPpos d 0.1Dt

MPpos 1.07




0.7

DPpos Dt



otherwise

Mn 1658kipft

Negative Moment Capacity Check (Appendix A6): Web Slenderness: Dt 34.7in Dcneg Dt ycr tbf 22.1in

2Dcneg 5.7 Es 1

tw

Fy

Moment ignoring concrete:

S Appendix A6 (for skew less than 20 deg).

A-136

Myt FySbotcr 6620.9kipin
My min MycMyt 6620.9kipin
Web Compactness:

Myc FsStopcr

21230.4kipin

Check for Permanent Deformations (6.10.4.2):
Dn max tslab ttf Dw ycyc tslab ttf 23.7in

Gov if yc tslab ttf yc crtDn 6.9in

fn

M4_SRV_II_neg

Gov Iz



min

1.0

Fy



1

fn

3.3ksi Steel stress on side of Dn



2

Dn

tw Atf

3.4

Rh

12 3 3
(12 2)

1

rw

5.7

Es Fy



Es



PWdcp

minrw


Dcpneg Dcneg


0.54

Fy
MPneg RhMy





2

0.09



19.1

Web Plastification: Flexure Factor:

2 Dcpneg tw

d PWdcp

0

Rpc

MPneg Myc

0.7

f 1.0

Rpt

MPneg Myt

2.2

Tensile Limit: Mr_neg_t fRptMyt 1238.7kipft Compressive Limit:

Local Buckling Resistance:

f

bbf 2tbf

7.8

rf

0.95 0.76 Es Fy

19.9

pf

0.38

Es Fy

9.2

Fyresid

max


min


0.7

Fy

Rh

Fy

Stopcr Sbotcr

Fy


0.5

Fy


35.0 ksi

MncLB

RpcMyc if f d pf





RpcMyc1







1



FyresidStopcr f pf

RpcMyc





rf



pf



otherwise

MncLB 1238.7kipft

Lateral Torsional Buckling Resistance:

Lb

Lstr 23

6.6 ft

rt

bbf

121



1 3



Dcnegtw bbftbf



2.3 in

Inflection point assumed to be at 1/6 span

A-137

Lp

1.0rt

Es Fy

56.2 in

h D tbf 26in

Cb 1.0

Jb

Dtw3



bbf



tbf

3





1



0.63 tbf





btf



ttf

3





1



0.63 ttf



3

3

bbf

3

btf

2.5 in4

Lr

1.95

rt

Es Fyresid



Jb 1 Sbotcrh

1



6.76

Fyresid

Sbotcrh 2

Es

Jb

236.9in

Fcr

Cb2Es
Lb 2

1



0.078

Jb Sbotcrh



Lb 2
rt



rt

MncLTB

RpcMyc if Lb d Lp

257.9ksi


minCb1




1



Fyresid Sbotcr RpcMyc





Lb Lr



Lp Lp





Rpc Myc Rpc Myc





if

Lp Lb d Lr

min FcrSbotcr RpcMyc if Lb ! Lr

MncLTB 1131.2kipft
Mr_neg_c fmin MncLBMncLTB 1131.2kipft
Governing negative moment capacity: Mr_neg

min Mr_neg_t Mr_neg_c

1131.2kipft

12. FLEXURAL STRENGTH CHECKS

Phase 1: First, check the stress due to the dead load on the steel section only. (LRFD 6.10.3 - Constructability Requirements

Reduction factor for construction const 0.9

Load Combination for construction Max Moment applied, Phase 1: (at midspan)
Maximum Stress, Phase 1:

1.25MDC

Mint_P1

1.25

MDC1_int



Lstr 2



Mext_P1

1.25

MDC1_ext

Lstr 2



fint_P1

M int_P1 y steel Izsteel

7 ksi

121.9kipft (Interior) 124.5kipft (Exterior)
(Interior)

fext_P1

M ext_P1 y steel Izsteel

7.1 ksi

(Exterior)

Stress limits:

fP1_max constFy

fint_P1 d fP1_max 1 fext_P1 d fP1_max 1

Phase 2: Second, check the stress due to dead load on the composite section (with barriers added)

Reduction factor for construction
Load Combination for construction
Max Moment applied, Phase 2: (at midspan)

const 0.9 1.25MDC
M2_STR_I 177.4kipft

A-138

Capacity for positive flexure: Check Moment:

Mn 1658kipft M2_STR_I d constMn 1

Phase 3: Next, check the flexural stress on the stringer during transport and picking, to ensure no cracking.

Reduction factor for construction
Load Combination for construction
Loads and stresses on stringer during transport and picking:

const 0.9 1.5MDC when dynamic construction loads are involved (Section 10).
M3_STR_I_neg 71.3kipft

Concrete rupture stress

fr 0.24 fcksi 0.5ksi

Concrete stress during construction not to exceed:

fcmax constfr 0.5ksi

fcconst

M 3_STR_I_neg y c Izn

fcconst d fcmax 1

0.2 ksi

Phase 4: Check flexural capacity under dead load and live load for fully installed continuous composite girders.

Strength I Load Combination M4_STR_I 489.2kipft M4_STR_I d fMn 1

f 1.0

M4_STR_I_neg 406.3kipft M4_STR_I_neg d Mr_neg 1

Strength III Load Combination M4_STR_III 136.4kipft
M4_STR_III d fMn 1

M4_STR_III_neg 170.6kipft M4_STR_III_neg d Mr_neg 1

Strength V Load Combination

M4_STR_V 408.6kipft M4_STR_V d fMn 1

M4_STR_V_neg 352.4kipft M4_STR_V_neg d Mr_neg 1

13. FLEXURAL SERVICE CHECKS Check service load combinations for the fully continuous beam with live load (Phase 4): under Service II for stress limits - M4_SRV_II 368.6kipft M4_SRV_II_neg 308.3kipft

under Service I for cracking -

M4_SRV_I_neg 267.9kipft
Ignore positive moment for Service I as there is no tension in the concrete in this case.

Service Load Stress Limits: Top Flange: ftfmax 0.95RhFy 47.5ksi Bottom Flange: fbfmax ftfmax 47.5ksi Concrete (Negative bending only): fr 0.5ksi
Service Load Stresses, Positive Moment:

A-139

Top Flange: Bottom Flange:

fSRVII_tf

M4_SRV_II

yc tslab Iz

fSRVII_tf d ftfmax 1

1.4 ksi

fbfs2

M4_SRV_II

tslab ttf Dw tbf yc Iz

fl 0

fbfs2

fl 2

d fbfmax

1

14 ksi

Service Load Stresses, Negative Moment:

Top (Concrete):

fcon.neg

M 4_SRV_I_neg y cneg nIzneg

0.8 ksi

Using Service I Loading

Bottom Flange: Check LL Deflection:

fcon.neg d fr 0

fbfs2.neg

M4_SRV_I_neg tslab ttf Dw tbf ycneg
Izneg

fbfs2.neg d fbfmax 1

20.1 ksi

DT 1.104in

DF

3 12

Lstr

DTDF

0.3 1717.4

from independent Analysis - includes 100% design truck (w/impact), or 25% design truck (w/impact) + 100% lane load Deflection distribution factor = (no. lanes)/(no. stringers)
Equivalent X, where L/X = Deflection*Distribution Factor

Lstr t 800 1 DTDF

14. SHEAR STRENGTH Shear Capacity based on AASHTO LRFD 6.10.9

Nominal resistance of unstiffened web:

Fy 50.0ksi

Dw 25.4in

Vp 0.58FyDwtw 338.8kip

tw 0.5in

v 1.0

k 5

A-140

C1

1.0 if Dw d 1.12 Esk

tw

Fy

1.57





Es

k



if

Dw ! 1.40

Esk

Dw 2 Fy tw

Fy





tw



1.12 Dw tw

Esk Fy


otherwise

Vn C1Vp 338.8kip

Vu d vVn 1

C1 1

15. FATIGUE LIMIT STATES:

Fatigue check shall follow LRFD Article 6.10.5. Moments used for fatigue calculations were found using an outside finite element analysis program.

First check Fatigue I (infinite life); then find maximum single lane ADTT for Fatigue II if needed.

Fatigue Stress Limits:

FTH_1 FTH_2 FTH_3

16ksi 12ksi 10ksi

Category B: non-coated weathering steel Category C': Base metal at toe of transverse stiffener fillet welds Category C: Base metal at shear connectors

Fatigue Moment Ranges at Detail Locations (from analysis):

MFAT_B 301kipft

MFAT_CP 285.7kipft

FATI 1.5

FATII 0.75

Constants to use for detail checks:

ADTTSL_INF_B 860 ADTTSL_INF_CP 660 ADTTSL_INF_C 1290

AFAT_B 120108 AFAT_CP 44108 AFAT_C 44108

MFAT_C 207.1kipft nfat 2 if Lstr d 40ft 1.0 otherwise

Category B Check: Stress at Bottom Flange, Fatigue I

fFATI_B

FATIMFAT_B tslab ttf Dw tbf yc
Iz

fFATI_B d FTH_1 0

fFATII_B

FATII FATI



fFATI_B

8.6 ksi

17.2 ksi

A-141

ADTTSL_B_MAX

ADTTSL_INF_B nfat

if fFATI_B d FTH_1

ADTTSL_B_MAX 345

AFAT_Bksi3 36575nfatfFATII_B3

otherwise

Category C' Check: Stress at base of transverse stiffener (top of bottom flange)

fFATI_CP

FATIMFAT_CP

tslab ttf Dw yc Iz

15.9 ksi

fFATI_CP d FTH_2 0

fFATII_CP

FATII FATI



fFATI_CP

7.9 ksi

ADTTSL_CP_MAX

ADTTSL_INF_CP nfat

if fFATI_CP d FTH_2

ADTTSL_CP_MAX 160

AFAT_CPksi3 36575nfatfFATII_CP3

otherwise

Category C Check: Stress at base of shear connectors (top of top flange)

fFATI_C

FATIMFAT_C

yc tslab Iz

1.1 ksi

fFATI_C d FTH_3 1

fFATII_C

FATII FATI



fFATI_C

0.6 ksi

ADTTSL_C_MAX

ADTTSL_INF_C nfat

if fFATI_C d FTH_3

ADTTSL_C_MAX 645

AFAT_Cksi3 36575nfatfFATII_C3

otherwise

FATIGUE CHECK: ADTTSL_MAX min ADTTSL_B_MAX ADTTSL_CP_MAXADTTSL_C_MAX

Ensure that single lane ADTT is less than ADTTSL_MAX 160 If not, then the beam requires redesign.

A-142

16. BEARING STIFFENERS Using LRFD Article 6.10.11 for stiffeners:

tp

5 in
8

bp 5in

b 1.0

Projecting Width Slenderness Check:

bp d 0.48tp

Es Fy

1

Stiffener Bearing Resistance:

tp_weld



5 16



in

*Check min weld size

Apn 2 bp tp_weld tp

Apn 5.9in2

Rsb_n 1.4ApnFy

Rsb_n 410.2kip

Rsb_r bRsb_n

Rsb_r 410.2kip

RDC 26.721kip RDW 2.62kip RLL 53.943kip

DC_STR_I 1.25 DW_STR_I 1.5 LL_STR_I 1.75

Ru DC_STR_IRDC DW_STR_IRDW LL_STR_IRLL

Ru d Rsb_r 1

Weld Check:

throat

tp_weld

2 2

Lweld Dw 23in

Aeff_weld throatLweld

Fexx 70ksi

e2 0.8

Rr_weld 0.6e2Fexx

Ru_weld

Ru 4Aeff_weld

Ru_weld d Ru_weld 1

Axial Resistance of Bearing Stiffeners:

Aeff 29tw tp tw 2bptp

Leff 0.75Dw

Ixp

29twtw3 tp 2bp tw 3

12

12

Iyp

tw tp 29tw 3 2bptp3

12

12

rp

min IxpIyp
Aeff

Q 1

for bearing stiffeners

c 0.9 Kp 0.75

9tw x tw

bp x tp 9tw x tw

bp x tp

Ru 131.7kip
throat 0.2in Lweld 19.4in Aeff_weld 4.3in2 Rr_weld 33.6ksi Ru_weld 7.7ksi
Aeff 10.3in2 Leff 19.1in Ixp 59.7in4 Iyp 27.3in4 rp 1.6in

Po QFyAeff 517.3kip

A-143

Pe

2EsAeff



Kp

Leff rp



2

38239.8kip





Po



Pn

0.658 Pe Po

if

Pe

t

0.44

Po

0.877Pe otherwise

Pr cPn

Pr 463kip

Ru d Pr 1

17. SHEAR CONNECTORS:

Shear Connector design to follow LRFD 6.10.10.

Stud Properties:

ds

7 in Diameter 8

hs 6in Height of Stud

cs tslab hs

cs t 2in 1

hs t 4 1 ds

ss 3.5in Spacing

ss t 4ds 1

ns 3 Studs per row

Asc

ds 2 2

btf ss ns 1 ds t 1.0in 1 2

Fu 60ksi

Fatigue Resistance:

Zr

5.5d

s2

kip in2

Zr 4.2kip

Qslab Aslab yc yslab

Vf 47.0kip

Vfat

VfQslab Iz

1.6 kip in

ps

nsZr Vfat

8.1 in

6ds d ps d 24in 1

Strength Resistance:

sc 0.85
fc 5ksi Ec 330000.151.5 fc ksi

4286.8 ksi

Qn min 0.5Asc fcEcAscFu

Qr scQn

Psimple min 0.85fcbefftsFyAsteel

Pcont Psimple min 0.45fcbefftsFyAsteel

nlines

Pcont Qrns

Pn 514.4kip
Asc 0.6in2 Qslab 253.8in3
Qn 36.1kip Qr 30.7kip Psimple 1190kip Pcont 1820kip nlines 19.8

A-144

Find required stud spacing along the girder (varies as applied shear varies)

i 0 23

0.00



1.414



4.947

8.480 12.013

15.546



19.079



22.612

26.145



29.678



33.210

33.917

x



ft

34.624

Vfi

36.037



36.743



40.276

43.809



47.342



50.875

54.408 57.941

61.474



65.007



67.833

61.5



59.2



56.8

54.4 52.0

49.5



47.1



44.7

42.7



40.6



40.6

40.6 kip 40.6

40.6



40.6



42.3

44.2



46.6



49.1

51.5 53.9

56.3



58.7



61.5

0

0

2

1

2

2 1.9

3 1.8

4 1.7

5 1.6

Vfati

VfiQslab Iz

6 7 8

1.6 1.5 kip
in 1.4

9 1.3

10 1.3

11 1.3

12 1.3

13 1.3

14 1.3

15 ...

0

0 6.2

1 6.4

2 6.7

3

7

4 7.3

5 7.7

Pmax

nsZr Vfati

6 7 8

8.1 8.5 in 8.9

9 9.4

10 9.4

11 9.4

12 9.4

13 9.4

14 9.4

15 ...

min Pmax 6.2in max Pmax 9.4in

18. SLAB PROPERTIES

This section details the geometric and material properties of the deck. Because the equivalent strip method is used in accordance with AASHTO LRFD Section 4, different loads are used for positive and negative bending.

Unit Weight Concrete Deck Thickness for Design Deck Thickness for Loads

wc 150pcf tdeck 8.0in td 10.5in

tdeck t 7in 1

Rebar yield strength

Fs 60ksi

Strength of concrete

fc 5ksi

Concrete clear cover

Bottom cb 1.0in

cb t 1.0in 1

Top ct 2.5in

ct t 2.5in 1

A-145

Transverse reinforcement

Bottom Reinforcing tb

6 in
8

Bottom Spacing stb 8in

stb t 1.5tb 1.5in 1

Design depth of Bar Girder Spacing

stb d 1.5tdeck 18in 1

Astb

12in tb 2 stb 2

0.7 in2

dtb

tdeck





cb



tb 2

6.6 in

spacingint_max 2ft 11in

spacingext 3 ft

Equivalent Strip, +M

wposM

26 6.6 spacingint_max in



ft



Equivalent Strip, -M

wnegM

48 3.0 spacingint_max in



ft



Once the strip widths are determined, the dead loads can be calculated.

Top Reinforcing Top Spacing

tt

5 in
8

stt 8in

stt t 1.5tt 1.5in 1

stt d 1.5tdeck 18in 1

Astt

12in tt 2 stt 2

0.5 in2

dtt

tdeck





ct



tt 2

5.2 in

wposM 45.3in wnegM 56.8in

19. PERMANENT LOADS

This section calculates the dead loads on the slab. These are used later for analysis to determine the design moments.

Weight of deck, +M

wdeck_pos wctdwposM

wdeck_pos 494.9plf

Weight of deck, -M

wdeck_neg wctdwnegM

wdeck_neg 620.7plf

Unit weight of barrier

wb 433.5plf

Barrier point load, +M

Pb_pos wbwposM

Pb_pos 1.63kip

Barrier point load, -M

Pb_neg wbwnegM

Pb_neg 2.05kip

20. LIVE LOADS

This section calculates the live loads on the slab. These loads are analyzed in a separate program with the permanent

loads to determine the design moments.

Truck wheel load

Pwheel 16kip

Impact Factor

IM 1.33

Multiple presence factors Wheel Loads

MP1 1.2 P1 IMMP1Pwheel

MP2 1.0 P2 IMMP2Pwheel

MP3 0.85 P3 IMMP3Pwheel

P1 25.54kip

P2 21.3kip

P3 18.09kip

21. LOAD RESULTS

The separate MathCAD design aides (available in Appendix of the final report) was used to analyze the deck as an 11-span continuous beam without cantilevered overhangs on either end, with supports stationed at girder locations. The dead and live loads were applied separately. The results are represented here as input values, highlighted.

A-146

Design Moments Mpos_deck 0.4kipft Mpos_LL 15.3kipft

Mpos 1.25Mpos_deck 1.75Mpos_LL

Mpos 27.3kipft

Mpos_dist

Mpos wposM

Mpos_dist

7.23 kipft ft

Mneg_deck 0.6kipft Mneg_LL 7.8kipft

Mneg 1.25Mneg_deck 1.75Mneg_LL

Mneg 14.4kipft

Mneg_dist

Mneg wnegM

Mneg_dist

3.04 kipft ft

22. FLEXURAL STRENGTH CAPACITY CHECK:

Consider a 1'-0" strip:

b 0.9

b 12in

1 0.85 if fc d 4ksi
0.85 0.05 fc 4 otherwise ksi

1 0.8

Bottom:

ctb

AstbFs 0.85fc1b

1 in

atb 1ctb 0.8in

Mntb Mrtb

Astb b

Fs





dtb



atb 2

bMntb

18.6 kipft ft

20.7 kipft ft

Mrtb t Mpos_dist 1

Top: ctt att

AsttFs 0.85fc1b

0.7 in

1ctt 0.5in

Mntt Mrtt

Astt ft

Fs





dtt



att 2

11.3 kipft ft

bMntt

10.2 kipft ft

Mrtt t Mneg_dist 1

23. LONGITUDINAL DECK REINFORCEMENT DESIGN:

Longitudinal reinforcement
Distribution Reinforcement (AASHTO 9.7.3.2)

lb

5 in
8

slb 12in

Aslb

12in lb 2 slb 2

0.3 in2

A%dist

min

220 spacingint_max

67

ft



100

Adist A%dist Astb 0.4in2

lt

5 in
8

slt 12in

Aslt

12in lt 2 slt 2

0.3 in2

67 % Aslb Aslt t Adist 1

A-147

24. DESIGN CHECKS

This section will conduct design checks on the reinforcing according to various sections in AASHTO LRFD.

CHECK MINIMUM REINFORCEMENT (AASHTO LRFD 5.7.3.3.2):

Modulus of Rupture Section Modulus

fr 0.37 fcksi 0.8ksi

Snc

btdeck2 6

Adeck tdeckb

128 in3 96 in2

Ec 4286.8ksi Es 29000ksi

A-148

ybar_tb

Adeck

tdeck 2



(n



1)Astbdtb

Adeck (n 1)Astb

4.1 in

Unfactored Dead Load Cracking Moment
Minimum Factored Flexural Resistance

ybar_tt

Adeck

tdeck 2



(n

1)Asttdtt

Adeck (n 1)Astt

4 in

Itb

btdeck3 12



Adeck



tdeck 2



ybar_tb2

(n



1)Astb

dtb



ybar_tb

2

538.3in4

Itt

btdeck3 12



Adeck



tdeck 2



ybar_tt2

(n



1)Astt

dtt



ybar_tt

2

515.8in4

Sc_tb

Itb tdeck ybar_tb

138.2in3

Sc_tt

Itt tdeck ybar_tt

130 in3

Mdnc_pos_t

kipft 1.25
ft

Mdnc_neg_t

0.542 kipft ft

Mcr_tb

Sc_tb fr max



ft

Mdnc_pos_t





Sc_tb

Snc



1

Sc_tb

fr

ft

9.5 kipft ft

Mcr_tt

Sc_tt fr max



ft

Mdnc_neg_t





Sc_tt

Snc



1

Sc_tt

fr

ft

9 kipft ft

S 5.7.3.3.2

Mr_min_tb Mr_min_tt

min 1.2Mcr_tb 1.33 Mpos_dist min 1.2Mcr_tt1.33 Mneg_dist

9.6 kipft ft
4 kipft ft

Mrtb t Mr_min_tb 1 Mrtt t Mr_min_tt 1

CHECK CRACK CONTROL (AASHTO LRFD 5.7.3.4): eb 1.0

MSL_pos 29.64kipft

MSL_pos_dist

MSL_pos wposM

fssb

MSL_pos_distbn Itb

dtbybar_tb

dcb

cb

tb 2

1.4 in

7.9 kipft ft
3.1 ksi

et 0.75

MSL_neg 29.64kipft

MSL_neg_dist

MSL_neg wnegM

fsst

MSL_neg_distbn Itt

dttybar_tt

dct

ct

tt 2

2.8 in

6.3 kipft ft
1.2 ksi

sb

1

dcb

0.7 tdeck dcb

1.3

sb

700ebkip sbfssbin



2dcb

171.9in

stb d sb 1

st

1

dct

0.7 tdeck dct

1.8

st

700etkip stfsstin



2dct

245.5in

stt d st 1

A-149

SHRINKAGE AND TEMPERATURE REINFORCING (AASHTO LRFD 5.10.8):

Ast

1.30btdeck kip if 0.11in2 d 1.30btdeck kip d 0.60in2

2 b tdeck Fs in

2 b tdeck Fs in

0.11in2 if 1.30btdeck kip 0.11in2 2 b tdeck Fs in

0.60in2 if 1.30btdeck kip ! 0.60in2 2 b tdeck Fs in

0.1 in2

Astb t Ast 1 Aslb t Ast 1

Astt t Ast 1 Aslt t Ast 1

SHEAR RESISTANCE (AASHTO LRFD 5.8.3.3):

0.9

2

45deg

b 1 ft

dv_tb

max

0.72

tdeck

dtb



atb 2

0.9d

tb

6.2 in

dv_tt

max

0.72

tdeck

dtt



att 2

0.9d

tt

5.8 in

dv min dv_tbdv_tt 5.8in

Vc 0.0316 fcksibdv 9.8kip

Vs 0kip Shear capacity of reinforcing steel

Vps 0kip Shear capacity of prestressing steel
Vns min Vc Vs Vps0.25fcbdv Vps 9.8kip

Vr Vns 8.8kip Total factored resistance

Vus 8.38kip

Total factored load

Vr t Vus 1

DEVELOPMENT AND SPLICE LENGTHS (AASHTO LRFD 5.11):

Development and splice length design follows standard calculations in AASHTO LRFD 5.11, or as dictated by the State DOT Design Manual.

25. DECK OVERHANG DESIGN (AASHTO LRFD A.13.4):

A-150

Deck Properties:

Deck Overhang Length Parapet Properties:

Lo 1ft 9in

Note: Parapet properties are per unit length. Compression reinforcement is ignored.

Cross Sectional Area

Ap 2.84ft2

Height of Parapet

Hpar 2ft 10in

Parapet Weight Width at base

Wpar wcAp 426plf wbase 1ft 5in Average width of wall

wwall

13in 9.5in 2

11.3 in

Height of top portion of parapet Height of middle portion of parapet Height of lower portion of parapet

h1 2ft h2 7in h3 3in

Width at top of parapet

width1 9.5in 9.5in

Width at middle transition of parapet Width at base of parapet

width2 12in 12in width3 1ft 5in 17in

Parapet Center of Gravity

b1 width1

b2 width2 width1

b3 width3 width2

h1

h2

h3

b12 2



1 2



h1

b2



b1



b2 3



CGp

h2

h3 b2

b3





b1



b2 2

b3



1 2



h2

b3



b1



b2

2b3 3

h1

h2

h3

b1

1 2

h1b2



h2 h3 b2 b3



1 2



h2

b3

6.3 in

Parapet Reinforcement Rebar spacing: Rebar Diameter:
Rebar Area:

Vertically Aligned Bars in Wall spa 12in

pa

5 in
8

Ast_p





pa



2

b

2 spa

0.3 in2

Horizontal Bars npl 5

pl

5 in
8

Asl_p

pl 2 2

0.3 in2

Cover:
Effective Depth:
Parapet Moment Resistance About Horizontal Axis:
Depth of Equivalent Stress Block:

cst 3in

dst

wbase

cst

pa 2

13.7 in

ext 1.0

ah

Ast_pFs 0.85fcb

0.4 in

csl 2in pa 2.6in

dsl

wwall

csl

pl 2

8.3 in

S 5.7.3.1.2-4 S 5.7.3.2.3

Moment Capacity of Upper Segment of Barrier (about longitudinal axis):

Average width of section Cover
Depth

w1 cst1
dh1

width1 width2

2 2in

w1

cst1



pa 2

10.7 in 8.4 in

Factored Moment Resistance

Mnh1

ext

Ast_pFs



dh1



ah 2

b

12.7 kipft ft

Moment Capacity of Middle Segment of Barrier (about longitudinal axis):

A-151

Average width of section Cover
Depth
Factored Moment Resistance

w2

width2 width3 2

cst2 3in

14.5 in

dh2

w2

cst2



pa 2

11.2 in

Mnh2

ext

Ast_pFs



dh2



ah 2

b

Parapet Base Moment Resistance (about longitudinal axis):

16.9 kipft ft

development in tension

cst3 3in minc_ta 1.5 if cst3 3pa spa pa 6pa

coverbase_vert 1.2

cst3

pa 2

1.2 otherwise

mdec_ta 0.8 if spa t 6in 0.8

1.0 otherwise

ldb_ta

max


1.25inAst_p fc

Fs kip

0.4pa

Fs ksi

if

pa d

11 in
8



ksi



2.70in Fs ksi
fc

if

pa =

14 in
8

ksi

3.50in Fs ksi
fc ksi

if

pa =

18 in
8

hooked bar developed in tension

ldt_ta lhb_ta

l db_ta minc_ta mdec_ta

38pa fc

10.6 in

ksi

14.4 in

minc 1.2

lap splice in tension

ldh_ta max 6in8paminclhb_ta 12.7in llst_ta max 12in1.3ldt_ta 18.7in

benefit ldt_ta ldh_ta 1.7in

ldev_a

7



13 16

in

Fdev

benefit ldev_a ldt_ta

0.7

Fd 0.75

Distance from NA to Compressive Face

ct_b

FdAst_pFs 0.85fc1b

0.3 in

S 5.7.3.1.2-4

3.3 in

A-152

Depth of Equivalent Stress Block
Nominal Moment Resistance

at 1ct_b 0.3in

Mnt

Fd

Ast_p

Fs



dst



at 2

15.6kipft

S 5.7.3.2.3 S 5.7.3.2.2-1

Factored Moment Resistance

Mcb

ext

Mnt ft

15.6 kipft ft

S 5.7.3.2

Average Moment Capacity of Barrier (about longitudinal axis):

Factored Moment Resistance about Horizontal Axis

Mc

Mnh1h1 Mnh2h2 Mcbh3 h1 h2 h3

13.8 kipft ft

Parapet Moment Resistance (about vertical axis):

Height of Transverse

y1 5in

Reinforcement in Parapet

y2 11.5in

y3 18in

y4 24.5in

y5 31in

Depth of Equivalent Stress a nplAsl_pFs

Block

0.85fcHpar

Concrete Cover in Parapet coverr 2in

Width of Parapet at
Transverse Reinforcement

x1

width3

y1 h3 b3 h2

15.6 in

x2

b1 b2

y2 h3 h2 b2 h1

11.8 in

x3

b1 b2

y3 h3 h2 b2 h1

11.2 in

x4

b1 b2

y4 h3 h2 b2 h1

10.5 in

x5

b1 b2

y5 h3 h2 b2 h1

9.8 in

0.6 in

coverrear

coverr

pa

pl 2

2.9 in

coverbase

cst3



pa

pl 2

3.9 in

coverf 2in

covert

x5 2

4.9 in

coverfront

2in

pa

pl 2

covertop covert 4.9in

Design depth

d1i x1 coverbase 11.6in

d1o x1 coverrear 12.6in

d2i x2 coverfront 8.9in

d2o x2 coverrear 8.9in

d3i x3 coverfront 8.2in

d3o x3 coverrear 8.2in

d4i x4 coverfront 7.6in

d4o x4 coverrear 7.6in

d5i x5 covertop 4.9in

d5o x5 covertop 4.9in

Nominal Moment Resistance - Tension on Inside Face

Mn1i Mn2i

ext Asl_p Fs d 1i



a 2



ext Asl_p Fs d 2i



a 2



208.3kipin 158.1kipin

Mn3i

ext Asl_p Fs d 3i



a 2



145.6kipin

Mn4i

ext Asl_p Fs d 4i



a 2



133.2kipin

A-153

Nominal Moment Resistance - Tension on Outside Face
Vertical Nominal Moment Resistance of Parapet Parapet Design Factors: Crash Level Transverse Design Force

Mn5i

ext Asl_p Fs d 5i



a 2



84.5kipin

Mwi Mn1i Mn2i Mn3i Mn4i Mn5i

Mn1o

extAsl_pFsd1o

a 2



18.9kipft

Mn2o

extAsl_pFsd2o

a 2



13.2kipft

Mn3o

extAsl_pFsd3o

a 2



12.1kipft

Mn4o

extAsl_pFsd4o

a 2



11.1kipft

60.8kipft

Mn5o

extAsl_pFsd5o

a 2



7kipft

Mwo Mn1o Mn2o Mn3o Mn4o Mn5o

62.3kipft

Mw

2Mwi Mwo 3

61.3kipft

CL "TL-4" Ft 13.5kip if CL = "TL-1"
27.0kip if CL = "TL-2" 54.0kip if CL = "TL-3" 54.0kip if CL = "TL-4" 124.0kip if CL = "TL-5" 175.0kip otherwise

54 kip

Lt 4.0ft if CL = "TL-1" 4.0ft if CL = "TL-2" 4.0ft if CL = "TL-3" 3.5ft if CL = "TL-4" 8.0ft if CL = "TL-5" 8.0ft otherwise

3.5 ft

Longitudinal Design Force Fl 4.5kip if CL = "TL-1" 9.0kip if CL = "TL-2" 18.0kip if CL = "TL-3" 18.0kip if CL = "TL-4" 41.0kip if CL = "TL-5"

58.0kip otherwise

Vertical Design Force (Down)

Fv 4.5kip if CL = "TL-1" 4.5kip if CL = "TL-2" 4.5kip if CL = "TL-3" 18.0kip if CL = "TL-4" 80.0kip if CL = "TL-5"

80.0kip otherwise

Critical Length of Yield Line Failure Pattern:

Mb 0kipft

18 kip 18 kip

Ll 4.0ft if CL = "TL-1" 4.0ft if CL = "TL-2" 4.0ft if CL = "TL-3" 3.5ft if CL = "TL-4" 8.0ft if CL = "TL-5" 8.0ft otherwise

3.5 ft

Lv 18.0ft if CL = "TL-1" 18ft 18.0ft if CL = "TL-2" 18.0ft if CL = "TL-3" 18.0ft if CL = "TL-4" 40.0ft if CL = "TL-5" 40.0ft otherwise

A-154

Lc

Lt 2

Lt 2 8Hpar Mb Mw

2

Mc

11.9 ft

S A13.3.1-2

Rw

2 2Lc

Lt 8Mb

8Mw

McLc2 Hpar

T

Rwb

Lc 2Hpar

6.6 kip

116.2kip

S A13.3.1-1 S A13.4.2-1

The parapet design must consider three design cases. Design Case 1 is for longitudinal and transverse collision loads under Extreme Event Load Combination II. Design Case 2 represents vertical collision loads under Extreme Event Load Combination II; however, this case does not govern for decks with concrete parapets or barriers. Design Case 3 is for dead and live load under Strength Load Combination I; however, the parapet will not carry wheel loads and therefore this case does not govern. Design Case 1 is the only case that requires a check.

Design Case 1: Longitudinal and Transverse Collision Loads, Extreme Event Load Combination II

DC - 1A: Inside face of parapet ext 1

DC 1.0

DW 1.0

LL 0.5

S A13.4.1 S Table 3.4.1-1

llip 2in
Adeck_1A tdeck llip wbase

152 in2

wbase 17in Ap 2.8ft2

Wdeck_1A wcAdeck_1A 0.2klf

MDCdeck_1A

DCWdeck_1A

llip

wbase 2

Wpar 0.1 kipft
ft

MDCpar_1A DCWpar llip CGp

0.3 kipft ft

Mtotal_1A Mcb MDCdeck_1A MDCpar_1A

16 kipft ft

0.4 klf

tt_add

5 in
8

stt_add 8in

Astt_p

12in tt 2 12in tt_add 2 stt 2 stt_add 2

0.9 in2

dtt_add

tdeck



ct



tt_add 2

ctt_p

Astt_pFs 0.85fc1b

1.4 in

5.2 in

att_p 1ctt_p 1.1in

Mntt_p

Astt_pFs ft





dtt_add



att_p 2

21.4 kipft ft

Mrtt_p bMntt_p

19.2 kipft ft

AsT Astt Astb 1.1in2

Mrtt_p t Mtotal_1A 1

Pn extAsTFs 67.4kip

Pn t T 1

Mu_1A

Mrtt_p 1



T Pn



17.4 kipft ft

Mu_1A t Mtotal_1A 1

A-155

DC - 1B: Design Section in Overhang

Notes:

Distribution length is assumed to increase based on a 30 degree angle from the face of parapet.

Moment of collision loads is distributed over the length Lc + 30 degree spread from face of parapet to

location of overhang design section.

Axial force of collision loads is distributed over the length Lc + 2Hpar + 30 degree spread from face of

parapet to location of overhang design section.

Future wearing surface is neglected as contribution is negligible.

Adeck_1B tdeckLo 168in2

Ap 2.8ft2

Wdeck_1B wcAdeck_1B 0.2klf

Wpar

MDCdeck_1B

DC

Wdeck_1B

Lo 2

0.2 kipft ft

MDCpar_1B DCWpar Lo llip CGp

0.5 kipft ft

0.4 klf

Lspread_B Lo llip width3 2in

spread 30deg

wspread_B Lspread_Btan(spread) 1.2in

Mcb_1B

McbLc Lc 2wspread_B

15.3 kipft ft

Mtotal_1B Mcb_1B MDCdeck_1B MDCpar_1B

15.9 kipft ft

Mrtt_p

19.2 kipft ft

Mrtt_p t Mtotal_1B 1

Pn 67.4kip

Pu

T Lc 2Hpar Lc 2Hpar 2wspread_B

6.5 kip

Pn t Pu 1

Mu_1B

Mrtt_p 1




Pu

Pn



17.4 kipft ft

Mu_1B t Mtotal_1B 1

DC - 1C: Design Section in First Span

Assumptions: Moment of collision loads is distributed over the length Lc + 30 degree spread from face of

parapet to location of overhang design section.

Axial force of collision loads is distributed over the length Lc + 2Hpar + 30 degree spread from

face of parapet to location of overhang design section.

Future wearing surface is neglected as contribution is negligible.

Mpar_G1 MDCpar_1B

0.5 kipft ft

Mpar_G2

0.137 kipft ft

(From model output)

M1 Mcb

15.6 kipft ft

M2

M1

Mpar_G2 Mpar_G1

4.7 kipft ft

bf 10.5in

Mc_M2M1

M1

1 4



bf



M1



M2

spacingint_max

14.1 kipft ft

A-156

Lspread_C wspread_C

Lo

llip



wbase



bf 4

Lspread_Ctan(spread)

4.6 in 2.7 in

Mcb_1C

Mc_M2M1Lc Lc 2wspread_C

13.6 kipft ft

Mtotal_1C Mcb_1C MDCdeck_1B MDCpar_1B

14.2 kipft ft

Mrtt_p

19.2 kipft ft

Mrtt_p t Mtotal_1C 1

Pn 67.4kip

PuC

T Lc 2Hpar Lc 2Hpar 2wspread_C

6.4 kip

Pn t PuC 1

Mu_1C

Mrtt_p 1




Pu

Pn



17.4 kipft ft

Mu_1B t Mtotal_1B 1

Compute Overhang Reinforcement Cut-off Length Requirement

Maximum crash load moment at theoretical cut-ff point:

Mc_max Mrtt

10.2 kipft ft

LMc_max

M2 M2



Mrtt M1



spacingint_max

2.1 ft

Lspread_D Lo llip wbase LMc_max 27.7in

wspread_D Lspread_Dtan(spread) 16in

Mcb_max

Mc_maxLc Lc 2wspread_D

8.3 kipft ft

extension max dtt_add12tt_add0.0625spacingint_max

cutt_off LMc_max extension

Att_add

tt_add 2 2

0.3 in2

33.2 in

mthick_tt_add 1.4 if tdeck ct t 12in 1

7.5 in

1.0 otherwise

mepoxy_tt_add

1.5

if

ct

3tt_add

stt_add 2



tt_add 6tt_add

1.5

1.2 otherwise

minc_tt_add min mthick_tt_addmepoxy_tt_add 1.7 1.5

mdec_tt_add

0.8 if stt_add t 6in 2

1

1.0 otherwise

A-157

ldb_tt_add

max


1.25inAtt_add fc

Fs kip

0.4tt_add

Fs ksi

if

tt_add d

11 in
8



ksi



2.70in Fs ksi
fc

if

tt_add =

14 in
8

ksi

ldb_tt_add 15in

3.50in Fs ksi
fc ksi

if

tt_add =

18 in
8

ldt_tt_add ldb_tt_addminc_tt_addmdec_tt_add 22.5in Cuttoffpoint LMc_max ldt_tt_add spacingint_max 13.2in extension past second interior girder

Check for Cracking in Overhang under Service Limit State: Does not govern - no live load on overhang.

25. COMPRESSION SPLICE:

See sheet S7 for drawing.

Ensure compression splice and connection can handle the compressive force in the force couple due to the negative moment over the pier.

Live load negative moment over pier:

MLLPier 541.8kipft

Factored LL moment:

MUPier 1.75MLLPier 948.1kipft

The compression splice is comprised of a splice plate on the underside of the bottom flange, and built-up angles on either side of the web, connecting to the bottom flange as well.

Calculate Bottom Flange Stress:

Composite moment of inertia:

Iz 7666.4in4

Distance to center of bottom flange from composite section centroid: Stress in bottom flange:
Calculate Bottom Flange Force: Design Stress:
Effective Flange Area:

ybf

tbf 2



Dw

ttf



tslab

yc

fbf

MUPier

ybf Iz

35.6 ksi

24 in

Fbf

max

fbf

2

Fy

0.75Fy

Aef bbftbf 6.4in2

42.8 ksi

Force in Flange:

Cnf FbfAef 274.1kip

Calculate Bottom Flange Stress, Ignoring Concrete:

Moment of inertia:

Izsteel 2798.5in4

Distance to center of bottom flange:

ybfsteel

tbf 2



Dw

ttf



ysteel

13 in

A-158

Stress in bottom flange:
Bottom Flange Force for design: Design Stress: Design Force:

fbfsteel

MUPier

ybfsteel Izsteel

52.9 ksi

Fcf

max

fbfsteel 2



Fy

0.75Fy

51.5 ksi

Cn max Fbf Fcf Aef 329.4kip

Compression Splice Plate Dimensions:

Bottom Splice Plate:

bbsp bbf 10in

tbsp 0.75in

Built-Up Angle Splice Plate Horizontal Leg: Built-Up Angle Splice Plate Vertical Leg:

basph 4.25in baspv 7.75in

tasph 0.75in taspv 0.75in

Total Area:

Acsp Absp Aasph Aaspv 25.5in2

Average Stress:

fcs

Proportion Load into each plate based on area:

Cn Acsp

12.9 ksi

Absp bbsptbsp 7.5in2 Aasph 2basphtasph 6.4in2 Aaspv 2baspvtaspv 11.6in2

Cbsp

CnAbsp Acsp

96.9 kip

Casph

CnAasph Acsp

82.3 kip

Caspv

CnAaspv Acsp

150.2kip

Check Plates Compression Capacity:

Bottom Splice Plate:

kcps 0.75 for bolted connection

lcps 9in

rbsp Pebsp

min

bbsp

tbsp3

tbsp

bbsp3



12

12

Absp

2EsAbsp

kcpslcps 2





rbsp

2208.5 kip

0.2 in

Qbsp

1.0 if bbsp d 0.45 Es

tbsp

Fy

1.34



0.76

bbsp





Fy

if 0.45

Es d bbsp d 0.91

Es



tbsp Es

Fy tbsp

Fy

0.53Es

Fy



bbsp tbsp



2

otherwise

Pobsp QbspFyAbsp 344.7kip

0.919

A-159

Pnbsp





Pobsp





0.658 Pebsp Pobsp

if

Pebsp t 0.44 Pobsp

0.877Pebsp otherwise

Pnbsp_allow 0.9Pnbsp 290.6kip

Check

322.9kip
"NG" if Cbsp t Pnbsp_allow "OK" if Pnbsp_allow t Cbsp

"OK"

Horizontal Angle Leg:

kcps 0.75 lcps 9in

for bolted connection

rasph Peasph

min

basph

tasph3

tasph

basph3



12

12

Aasph

2EsAasph

kcpslcps 2





rasph

938.6kip

0.153in

Qasph

1.0 if basph d 0.45 Es

tasph

Fy

1

1.34



0.76

basph





Fy

if 0.45

Es d basph d 0.91

Es



tasph Es

Fy tasph

Fy

0.53Es

Fy



basph tasph



2

otherwise

Poasph QasphFyAasph 318.7kip

Vertical Angle Leg:

Pnasph





Poasph





0.658 Peasph Poasph

if

Peasph t 0.44 Poasph

276.5kip

0.877Peasph otherwise

Pnasph_allow 0.9Pnasph 248.9kip

Check2 "NG" if Casph t Pnasph_allow

kcps 0.75 for bolted connection

"OK" if Pnasph_allow t Casph

lcps 9in

raspv

min

baspv

taspv3

taspv

baspv3



12

12

Aaspv

0.153in

Peaspv

2EsAaspv

kcpslcps 2





raspv

1711.6 kip

"OK"

A-160

Qaspv

1.0 if baspv d 0.45 Es

taspv

Fy

1

1.34



0.76

baspv





Fy

if 0.45

Es d baspv d 0.91

Es



taspv Es

Fy taspv

Fy

0.53Es

Fy



baspv taspv



2

otherwise

Poaspv QaspvFyAaspv 581.2kip

Pnaspv





Poaspv





0.658 Peaspv Poaspv

if

Peaspv t 0.44 Poaspv

504.2kip

0.877Peaspv otherwise

Pnaspv_allow 0.9Pnaspv 453.8kip

Check3 "NG" if Caspv t Pnaspv_allow

"OK" if Pnaspv_allow t Caspv

"OK"

Additional Checks: Design Bolted Connections of the splice plates to the girders, checking for shear, bearing, and slip critical connections.

26. CLOSURE POUR DESIGN: See sheet S2 for drawing of closure pour. Check the closure pour according to the negative bending capacity of the section. Use the minimum reinforcing properties for design, to be conservative.

Asteel 24.5in2

Art 1.4in2

Arb 1.9in2

cgsteel tslab ysteel 21.3in

cgrt

3in 1.5 5 in 8

Overall CG: Aneg Asteel Art Arb 27.8in2

3.9 in

Moment of Inertia: Izstl 3990in4

cgrb

tslab



1in



1.5

5 8

in

6.1 in

cgneg

Asteelcgsteel Artcgrt Arbcgrb Aneg

19.4 in

Ineg Izstl Asteel cgsteel cgneg 2 Art cgrt cgneg 2 Arb cgrb cgneg 2 4748.8in4

Section Moduli:

Stop_neg Sbot_neg

Ineg cgneg cgrt

306.5in3

Ineg

tslab ttf Dw tbf cgneg

311.4in3

rneg

Ineg 13.1in Aneg

Concrete Properties: fc 5ksi Ec 4286.8ksi

Steel Properties:

Fy 50ksi Es 29000ksi

Lbneg 13.42ft

A-161

Negative Flexural Capacity:

Slenderness ratio for compressive flange: fneg

bbf 2tbf

7.8

Fyr 0.7Fy

Limiting ratio for compactness:

pfneg

0.38

Es Fy

9.2

Limiting ratio for noncompact Hybrid Factor:

rfneg

0.56

Es Fyr

16.1

Rh 1

35 ksi

Flange compression resistance:

Dcneg2

Dw 2

12.7 in

awc

2Dcneg2tw bbftbf

1.8

Rb

1.0 if 2 Dcneg2 d 5.7 Es

tw

Fy

min1.01

awc





2

Dcneg2



5.7

Es



otherwi



1200 300awc tw

Fy

Rb 1

Fnc1

RbRhFy if fneg d pfneg


1




1



Fyr RhFy





fneg rfneg

pfneg pfneg





Rb Rh Fy





otherwise

Fnc1 50ksi

Lateral Torsional Buckling Resistance:

rtneg

bbf

121




Dcneg2tw

3bbftbf



2.5 in

Lpneg

1.0rtneg

Es Fy

60.9 in

Lrneg

rtneg

Es Fyr

228.6in

Compressive Resistance:

Cb 1

Fnc2

RbRhFy if Lbneg d Lpneg


minCb1 1


Fyr RhFy





Lbneg Lpneg Lrneg Lpneg

Rb Rh Fy Rb Rh F

Fnc2 41ksi

Fnc min Fnc1Fnc2 41ksi

Tensile Flexural Resistance:

Fnt RhFy 50ksi

For Strength

A-162

Ultimate Moment Resistance:

Fnt_Serv 0.95RhFy 47.5ksi

For Service

Mn_neg min FntStop_negFncSbot_neg 1065.1kipft

MUPier 948.1kipft

from external FE analysis

Check4 Mn_neg t MUPier 1
For additional design, one may calculate the force couple at the section over the pier to find the force in the UHPC closure joint. This force can be used to design any additional reinforcement used in the joint.

A-163

File Name: Prestressed Concrete Girder-80ft.xmcd

DECKED PRECAST PRESTRESSED CONCRETE GIRDER DESIGN FOR ABC

Unit Definition:

kcf { kipft 3

This example is for the design of a superstructure system that can be used for rapid bridge replacement in an Accelerated Bridge Construction (ABC) application. The following calculations are intended to provide the designer guidance in developing a similar design with regard to design considerationS characteristic of this type of construction, and they shall not be considered fully exhaustive.
Overall Width, W

Barrier Width, Wb

Joint Width, Wj

Roadway Width, Wr Slope, CS

S Wj 2


Beam Spacing, S TYPICAL SECTION THROUGH SPAN

Lend Bridge Geometry:

Design Span Length, L Girder Length, Lg

GIRDER ELEVATION

L 80ft

W 63ft

Smax 8ft

Ng

W Wj

ceil



Smax

8

S W Wj 7.938ft Ng

Lend 2ft Wb 1.5ft Wj 0.5ft

skew 0deg

Minimum number of girders in cross-section

Girder spacing

A-164

ORDER OF CALCULATIONS

1. Introduction 2. Design Philosophy 3. Design Criteria 4. Beam Section 5. Material Properties 6. Permanent Loads 7. Precast Lifting Weight 8. Live Load 9. Prestress Properties 10. Prestress Losses 11. Concrete Stresses 12. Flexural Strength 13. Shear Strength 14. Splitting Resistance 15. Camber and Deflections 16. Negative Moment Flexural Strength

1.

INTRODUCTION

The bridge that is designed in this example consists of precast prestressed concrete girders with a top flange equal to the beam spacing, so the top flange will be the riding surface of the designed bridge. The purpose for these girders is to rapidly construct the bridge by providing a precast deck on the girders, which eliminates cast-in-place decks in the field and improves safety.

The concepts used in this example have been taken from on-going research, which focuses on the benefits of decked precast beams and promoting widespread acceptance from transportation and construction industries. The cross-section is adapted from the optimized girder sections recommended by NCHRP Project No. 12-69, Design and Construction Guidelines for Long-Span Decked Precast, Prestressed Concrete Girder Bridges. The girder design has not taken into account the option to re-deck due to the final re-decked girder, without additional prestressed, having a shorter life span. Use of stainless steal rebar and the application of a future membrane can get ride of the need to replace the deck. This case is included in "re-deckability".

The bridge used in this example is a general design of a typical bridge in Georgia. The calculations can be modified for single-span and multiple-span bridges due to the beam design moments are not reduced for continuity at intermediate supports (continuity details are not shown in this example). The cross-section consists of a four-lane roadway with normal crown, with standard shoulder lengths and barrier walls. The precast prestressed concrete girder has been uniformly designed to simplify bearing details. The girder flanges are 9'' at the tips, imitating a 8'' slab with a '' allowable wear and another '' for smoothness and profile adjustments.

This example is intended to illustrate design aspect specific to precast prestressed concrete girders used for ABC application. Girders with uncommon cross-sections, high self-weight, or unconventional load application create major concerns and more detailed calculations must be done.

A-165

2.

DESIGN PHILOSOPHY

The geometry of the section is based on GDOT standards and general bridges across the state of Georgia. Depth variations are dependent on the construction company but must maintain the shapes of the top flange and the bottom bulb.

Concrete strengths can vary but are mostly between 6 ksi and 10 ksi. For the purpose of these calculations the concrete with a 28-day minimum compressive strength of 8 ksi is used. Due to its casting sequence this beam is unable to take advantage of composite sequences along with tension at the bottom of the beam at the service limit state being limited. This is further discussed in section 4 along with end region stresses being critical. Therefore the minimum concrete strength at release must be 80 percent of the 28-day compressive strength, which increases the allowable stresses at the top and bottom of the section. The prestressed steel can also be optimized to minimize stresses at the end region.

The prestressed steel is arranged in a draped, or harped, pattern to maximize the midspan effectiveness while it minimizes the failure at the end of the beam where is concrete is easily overstressed due to the lack of dead load acting on the beam. The strand group is optimized at the midspan by bundling the strands between hold-points, maximizing the stiffness of the strand group. The number and deflection angles are depended on the type of single strands you are using for the girder. In longer span cases the concrete at the end of the girder will be too large and will debond. Without harped strands it is unlikely to reduce stresses to the allowable limit, since harped strands are required this method of stress relief will be used without debonding for long spans.

3.

DESIGN CRITERIA

Criteria has been selected to govern the design of these concrete girders while following provisions set by AASHTO, GDOT design specifications, as well as criteria of past projects and current research related to ABC and decked precast sections. A summary of the limiting design values are categorized as section constraints, prestress limits, and concrete limits.

Section Constraints:

Wpc.max 200kip
Smax 8ft Prestress Limits:

Upper limit on the weight of the entire precast element, based on common lifting and transport capabilities without significantly increasing time and/or cost due to unconventional equipment or permits
Upper limit on girder spacing and, therefore, girder flange width (defined on first page)

Fhd.single 4kip

Maximum hold-down force for a single strand

Fhd.group 48kip

Maximum hold-down force for the group of harped strands

Stress limits in the prestressing steel immediately prior to prestress and at the service limit state after all losses are as prescribed by AASHTO LRFD.

A-166

3.

DESIGN CRITERIA (cont'd)

Concrete Limits:

Allowable concrete stresses meet standards set by AASHTO LRFD with one exception that at Service III Limit State, allowable bottom fiber tension when camber leveling forces are to be neglected, regardless of exposure, are to be 0-ksi. Minimum strength of concrete at release is 80 percent of the 28-day minimum compressive strength (f-ksi).

ft.all.ser 0ksi

Allowable bottom fiber tension at the Service III Limit State, when camber leveling forces are to be neglected, regardless of exposure

As previously mentioned, release concrete strength is specified as 80 percent of the minimum 28-day compressive strength to maximize allowable stresses in the end region of beam at release.

fc.rel(f ) 0.80f

Minimum strength of concrete at release

Due to various lifting and transportation conditions, stresses in the concrete need to be considered. A "no cracking" approach is used for allowable tension due to reduced lateral stability after cracking. Assuming the girders will be lifted before the 28-day minimum strength is attained, the strength of concrete during lifting and transportation is assumed to be 90 percent of the 28-day minimum compressive strength. A dynamic dead load allowance of 30 percent is used for compression during handling. A factor of safety (FS) of 1.5 is used against cracking during handling.

DIM 30%

Dynamic dead load allowance

fc.erec(f ) 0.90f

FSc 1.5

ft.erec(f )

0.24 f ksi FSc

Assumed attained concrete strength during lifting and transportation Factor of safety against cracking during lifting transportation Allowable tension in concrete during lifting and transportation to avoid cracking

A-167

4.

BEAM SECTION

Use trapezoidal areas to define the cross-section. The flange width is defined as the beam spacing less the width of the longitudinal closure joint to reflect pre-erection conditions. Live load can be conservatively applied to this section, as well.

h 49.5in

Beam section depth

tflange 9in tsac 1in

Flange thickness at tip

Total sacrificial depth for grinding and wear

y

b1 26in b2 26in b3 6in b4 6in b5 10in b6 42in b7 89.25in

b2 26in b3 6in b4 6in b5 10in b6 42in b7 S Wj b8 S Wj

d3 h tsac d

Gross Section Properties

d1 6in d2 4.5in
d4 2in d5 2in d6 0in d7 tflange tsac
d3 26in

b n+1

bn

b n-1 bn-2

d n-2

b3 b2
b1

d2
d1 x

TYPICALGIRDERSECTIONCOMPR ISED OFnTRAPEZOIDALR EGIONS

dn dn-1

bf 89.25in Ag 1166in2 Ixg 310192in4
ytg 14.938in Stg 20765.3in3 Iyg 487758in4

ybg 33.562in Sbg 9242.4in3

Precast girder flange width Cross-sectional area (does not include sacrifical thickness) Moment of inertia (does not include sacrificial thickness) Top and bottom fiber distances from neutal axis (positive up) Top and bottom section moduli Weak-axis moment of inertia

GIRDER SECTION PLOT (N.T.S.) 51.5

44.812

38.125

31.437

24.75

18.062

11.375

4.687

2

50 40 30 20 10 0

10 20 30 40

50

A-168

5.

MATERIAL PROPERTIES

These properties are standard (US units) values with equations that can be found in AASHTO LRFD Bridge Design Specifications.

Concrete: fc 8ksi
fci fc.rel fc

6.4 ksi

c .150kcf

K1 1.0

Eci

33000

K1



c kcf

1.5

fciksi

4850 ksi

Ec

33000K1



c kcf



1.5

fcksi

5422 ksi

Minimum 28-day compressive strength of concrete Minimum strength of concrete at release Unit weight of concrete Correction factor for standard aggregate (5.4.2.4) Modulus of elasticity at release (5.4.2.4-1)
Modulus of elasticity (5.4.2.4-1)

fr.cm 0.37 fcksi 1.047ksi fr.cd 0.24 fcksi 0.679ksi H 70

Modulus of rupture for cracking moment (5.4.2.6) Modulus of rupture for camber and deflection (5.4.2.6) Relative humidity (5.4.2.3)

Prestressing Steel:

fpu 270ksi

fpy 0.9fpu 243ksi

fpbt.max 0.75fpu 202.5ksi

fpe.max 0.80fpy 194.4ksi

Ep 28500ksi

dps 0.5in Ap 0.153in2

Nps.max 40

npi

Ep Eci

5.9

np

Ep Ec

5.3

Mild Steel:

Ultimate tensile strength Yield strength, low-relaxation strand (Table 5.4.4.1-1) Maximum stress in steel immediately prior to transfer Maximum stress in steel after all losses Modulus of elasticity (5.4.4.2) Strand diameter Strand area Maximum number of strands in section Modular ratio at release
Modular ratio

A-169

fy 60ksi Es 29000ksi

Specified minimum yield strength Modulus of elasticity (5.4.3.2)

A-170

6.

PERMANENT LOADS

Permanent loads or dead loads that must be considered are self-weight, diaphragms, barriers, and future wearing surface. The barrier can be cast to the beam before it is taken on sight or attached to the bridge after the joints have reached sufficient strength. Distribution of the barriers weight should be established once you decide when it would be attached to the bridge. For this example the barrier has been cast on the exterior girder in the casting yard, before shipping but after release of prestresses. Due to this the dead load is increased on the exterior girders but it eliminates the time-consuming task that would have been completed in the field.

BeamLoc 1

Location of beam within the cross-section (0 - Interior, 1 - Exterior)

Load at Release: c.DL .155kcf
Ag.DL Ag tsac S Wj 1255.25in2

Concrete density used for weight calculations Area used for weight calculations, including sacrificial thickness

wg Ag.DLc.DL 1.351klf

Uniform load due to self-weight, including sacrificial thickness

Lg L 2Lend 84ft

Mgr(x)

wgx 2

Lg



x

Vgr(x)

wg



Lg 2



x

Span length at release Moment due to beam self-weight (supported at ends) Shear due to beam self-weight (supported at ends)

Load at Erection:

Mg(x)

wgx (L x) 2

Vg(x)

wg



L 2



x

Moment due to beam self-weight Shear due to beam self-weight

wbar 0.430klf

Uniform load due to barrier weight, exterior beams only

wbar if BeamLoc = 1 wbar0 0.43klf Redfine to 0 if interior beam (BeamLoc = 0)

Mbar(x)

wbarx (L x) 2

Vbar(x)

wbar



L 2



x

Moment due to beam self-weight Shear due to beam self-weight

A-171

6.

PERMANENT LOADS (cont'd)

Load at Service:

pfws 25psf

wfws pfwsS 0.198klf

Mfws(x)

wfwsx (L x) 2

Vfws(x)

wfws



L 2



x

wj Wjd7c.DL 0.052klf

Mj(x)

wjx (L x) 2

Vj(x)

wj



L 2



x

Assumed weight of future wearing surface Uniform load due to future wearing surface Moment due to future wearing surface Shear due to future wearing surface
Uniform load due to weight of longitudinal closure joint Moment due to longitudinal closure joint Shear due to longitudinal closure joint

A-172

7.

PRECAST LIFTING WEIGHT

For Accelerated Bridge Construction the beams are casted in a factory and transported to the job site. When they arrive at the site they must be lifted and put into place. When designing we have to consider the weight of each slab to insure safety and design for possible cracking.

Precast Superstructure
Wg wg wbar Lg 149.6kip

Substructure Precast with Superstructure

Lcorb 1ft

Bcorb bf

bf 89.25in

Dcorb 1.5ft Vcorb LcorbBcorbDcorb

11.16ft3

Precast girder, including barrier if necessary
Length of approach slab corbel Width of corbel cast with girder Average depth of corbel Volume of corbel

Lia 2.167ft

Length of integral abutment

Lgia 1.167ft

Length of girder embedded in integral abutment

Bia S Wj 7.438ft

Width of integral abutment cast with girder

Dia h 4in 53.5in
Via Vcorb LiaBiaDia Ag tflangebf Lgia

80.07ft3

Depth of integral abutment Volume of integral abutment cast with girder

Wia Viac 12kip

Weight of integral abutment cast with girder

Lsa 2.167ft

Length of semi-integral abutment

Lgsa 4in

Length of girder embedded in semi-integral abutment

Bsa S Wj 7.438ft

Width of semi-integral abutment cast with girder

Dsa h 16in 65.5in
Vsa Vcorb LsaBsaDsa Ag tflangebf Lgsa

Depth of semi-integral abutment 98.29ft3 Volume of semi-integral abutment cast with girder

Wsa Vsac 15kip

Weight of semi-integral abutment cast with girder

A-173

Semi-Integral Abutment Backwall

Integral Abutment Backwall

A-174

8.

LIVE LOAD

When considering Live Loads you must refer to the vertical load section HL-93 in the AASHTO manual. If the project you are working on requires the bridge to support construction loads at any stage, these loads must be considered separately and applied. The longitudinal joints are designed for full moment connections so the beams will act as a unit when sufficiently connected. The distribution factors are then computed for cross-section type "j" (defined in AASHTO 4.6.2.2). When calculating the stiffness parameter, the constant- depth region at the top flange is treated like the slab and the remaining area of the beam will be considered a non-composite beam.

Definitions:

Ibb

=

Abb

=

ybb

=

ts

=

moment of inertia of section below the top flange area of beam section below the top flange distance of top fiber below the top flange from neutral axis thickness of slab not including sacrificial thickness

Distribution Factors for Moment: From Table 4.6.2.2.2b-1 for moment in interior girders,

Ibb 86022in4

Abb 452in2

eg

h





tsac



ts 2



ybb

28.216 in

Kg 1.0Ibb Abbeg2 445885in4

Moment of inertia of section below the top flange Area of beam section below the top flange Distance between c.g.'s of beam and flange Longitudinal stiffness parameter (Eqn. 4.6.2.2.1-1)

Verify this girder design is within the range of applicability for Table 4.6.2.2.2b-1.
CheckMint if (S d 16ft)(S t 3.5ft)ts t 4.5in ts d 12.0in (L t 20ft)(L d 240ft) "OK" "No Good" CheckMint if (CheckMint = "OK" )Ng t 4 Kg t 10000in4Kg d 7000000in4 "OK" "No Good"
CheckMint "OK"

gmint1

0.06





S 14

ft



0.4



S L



0.3



Kg 0.1 Lts3

0.455

gmint2

0.075





S 9.5ft



0.6

S L



0.2

Kg 0.1 Lts3

0.635

gmint max gmint1gmint2 0.635

Single loaded lane Two or more loaded lanes Distribution factor for moment at interior beams

A-175

8.

LIVE LOAD (cont'd)

From Table 4.6.2.2.2d-1 for moment in exterior girders,

de

S 2



Wb

29.625 in

Distance from centerline of exterior beam to edge of curb or barrier

CheckMext if de t 1ft de d 5.5ft Ng t 4 "OK" "No Good" "OK"

For a single loaded lane, use the Lever Rule.

gmext1

S 0.5bf Wb 5ft S

0.65

em

0.77 de 9.1ft

1.041

gmext2 emgmint 0.661

gmext max gmext1gmext2 0.661

Single loaded lane Correction factor for moment (Table 4.6.2.2.2d-1) Two or more loaded lanes Distribution factor for moment at exterior beams

Distribution Factors for Shear: From Table 4.6.2.2.3a-1 for shear in interior girders,
Verify this girder design is within the range of applicability for Table 4.6.2.2.3a-1.
CheckVint if (S d 16ft)(S t 3.5ft)ts t 4.5in ts d 12.0in (L t 20ft)(L d 240ft) "OK" "No Good" CheckVint if (CheckMint = "OK" )Ng t 4 "OK" "No Good"
CheckVint "OK"

gvint1

0.36





S 25ft



0.678

gvint2

0.2





S 12ft







S 35ft



2.0

0.81

gvint max gvint1 gvint2 0.81

Single loaded lane Two or more loaded lanes Distribution factor for shear at interior beams

A-176

8.

LIVE LOAD (cont'd)

From Table 4.6.2.2.3b-1 for shear in exterior girders,

For a single loaded lane, use the Lever Rule.

CheckVext if de t 1ft de d 5.5ft Ng t 4 "OK" "No Good" "OK"

g1

S 0.5bf Wb 5ft S

0.65

ev

0.6 de 10ft

0.847

g2 evgvint 0.686

gvext max g1g2 0.686

Single loaded lane (same as for moment) Correction factor for shear (Table 4.6.2.2.3b-1) Two or more loaded lanes Distribution factor for shear at exterior beams

From Table 4.6.2.2.3c-1 for skewed bridges,

skew 0deg
CheckSkew if ( d 60deg)(3.5ft d S d 16ft)(20ft d L d 240ft) Ng t 4 "OK" "No Good" "OK"

cskew

1.0



0.20

Lts3 Kg



0.3

tan(

)

1.00

Correction factor for skew

A-177

8.

LIVE LOAD (cont'd)

Design Live Load Moment at Midspan:

wlane 0.64klf

Design lane load

Ptruck 32kip

Design truck axle load

IM 33%

Dynamic load allowance (truck only)

Mlane(x)

wlanex (L x) 2

(x) xL x2 L

Design lane load moment Influence coefficient for truck moment calculation

Mtruck(x)

Ptruck(x)max9x(L

x) 14ft(3x 4x(L x)



L)

9(

L x) 84 4(L x)

ft

Design truck moment

MHL93(x) Mlane(x) (1 IM)Mtruck(x)

HL93 design live load moment per lane

Mll.i(x) MHL93(x)gmint

Design live load moment at interior beam

Mll.e(x) MHL93(x)gmext
Mll(x) if BeamLoc = 1 Mll.e(x) Mll.i(x)

Design live load moment at exterior beam Design live load moment

Design Live Load Shear:

Vlane(x)

wlane



L 2



x

Vtruck(x)

Ptruck

9L



9x 4L

84ft



VHL93(x) Vlane(x) (1 IM)Vtruck(x)

Vll.i(x) VHL93(x)gvint

Vll.e(x) VHL93(x)gvext
Vll(x) if BeamLoc = 1 Vll.e(x) Vll.i(x)

Design lane load shear Design truck shear HL93 design live load shear Design live load shear at interior beam Design live load shear at exterior beam Design live load shear

A-178

9.

PRESTRESS PROPERTIES

Due to tension at the surface limit state be reduced to account for camber leveling forces, the prestress force required at the midspan is expected to be excessive at the ends when released. Not measuring the reduction of prestress moments. Estimate prestress losses at the midspan to find trial prestress forces, that will occur in the bottom tension fibers, that are less than allowable. Compute immediate losses in the prestressed steel and check released stresses at the end of the beam. Once you satisfy end stresses, estimate total loss of prestress. As long as these losses are not drastically different from the assumed stresses, the prestress layout should be acceptable. Concrete stress at all limit states are in Section 9.

yp.est 5in ycgp.est ybg yp.est 28.56in fp.est 25%

Assumed distance from bottom of beam to centroid of prestress at midspan Eccentricity of prestress from neutral axis, based on assumed location Estimate of total prestress losses at the service limit state

Compute bottom fiber service stresses at midspan using gross section properties.

X L 2
Mdl.ser Mg(X) Mfws(X) Mj(X) Mbar(X) 1625kipft

Distance from support Total dead load moment

fb.serIII

Mdl.ser 0.8Mll(X) Sbg

fpj fpbt.max 202.5ksi

3.521ksi

Total bottom fiber service stress Prestress jacking force

fpe.est fpj 1 fp.est 151.9ksi

Estimate of effective prestress force

Aps.est

fb.serIII ft.all.ser





Ag

1

fpe.est Agycgp.est



Sbg

Nps.est

Aps.est

ceil



Ap

39

5.873in2

Estimated minimum area of prestressing steel Estimated number of strands required

Nps 38

Number of strands used ( Nps.max 40 )

The number above is used for the layout strand pattern and to compute the actual location of the strand group. After this is done the required area is computed again. If the estimated location is accurate the number of strands should be equal to the number of strands that we calculated above. The number of strands that was estimated was based on our assumed prestressed losses and gross section properties, which may not accurately reflect the final number of strands required for the design. These stresses for concrete are evaluated in Section 10. The geometry is assuming a vertical spacing of 2" between straight spans, as well as 2" for harped strands at the end of the beam. Harped strands are bundled at the midspan where the centroid is 5" from the bottom.

A-179

9.

PRESTRESS PROPERTIES (cont'd)

Nh 2 if Nps d 12 4 if 12 Nps d 24 6 if 24 Nps d 30
6 Nps 30 if Nps ! 30

Nh.add 16

Nh

min

Nh



Nh.add

16

2



floor

Nps 4

yh

1in (2in)1 0.5Nh 1



2

yhb 5in

Ns Nps Nh

Nh 14

Assumes all flange rows are filled prior to filling rows in web above the flange, which maximized efficiency. Use override below to shift strands from flange to web if needed to satisfy end stresses.

Nh 16

Additional harped strands in web (strands to be moved from flange to web)
16 strands or half of total strands maximum harped in web

yh 10in Ns 22

Centroid of harped strands from bottom, equally spaced Centroid of harped strands from bottom, bundled
Number of straight strands in flange

ys 1in 2in if Ns d 10

ys 4.273in Centroid of straight strands from bottom

(4in)Ns 20in Ns

if 10 Ns d 20

(6in)Ns 60in Ns

if 20 Ns d 24

3.5in otherwise

yp

Nsys Nhyhb Ns Nh

4.579in

Centroid of prestress from bottom at midspan

ycgp ybg yp 28.98in

Aps.req

fb.serIII ft.all.ser





Ag

fpe.est 1 Agycgp



Sbg

5.806in2

Eccentricity of prestress from neutral axis Estimated minimum area of prestressing steel

Nps.req

Aps.req

ceil

38

Ap

Estimated number of strands required

CheckNps if Nps d Nps.max Nps.req d Nps "OK" "No Good" "OK"

Aps.h NhAp 2.448in2 Aps.s NsAp 3.366in2 Aps Aps.h Aps.s 5.814in2

Area of prestress in web (harped) Area of prestress in flange (straight) Total area of prestress

A-180

9.

PRESTRESS PROPERTIES (cont'd)

Compute transformed section properties based on prestress layout.
Transformed Section Properties

Initial Transformed Section (release):

Final Transformed Section (service):

Ati 1194.4in2 Ixti 333442in4 ytti 15.626in ycgpi 28.295in ybti 32.874in

Stti 21339in3 Scgpi 11784in3 Sbti 10143in3

Atf 1190.7in2 Ixtf 330546in4 yttf 15.540in ycgpf 28.381in ybtf 32.960in

Sttf 21270in3 Scgpf 11647in3 Sbtf 10029in3

Determine initial prestress force after instantaneous loss due to elastic shortening. Use transformed properties to compute stress in the concrete at the level of prestress.

Pj fpjAps 1177.3kip

fcgpi

Pj



1 Ati



ycgpi
Scgpi



Mgr

Lg 2



Scgpi

2.599ksi

Jacking force in prestress, prior to losses
Stress in concrete at the level of prestress after instantaneous losses

fpES npifcgpi 15.273ksi

Prestress loss due to elastic shortening (5.9.5.2.3a-1)

fpi fpj fpES 187.227ksi

Initial prestress after instantaneous losses

Pi fpiAps 1088.5kip

Initial prestress force

Determine deflection of harped strands required to satisfy allowable stresses at the end of the beam at release.

fc.all.rel 0.6fci 3.84ksi
ft.all.rel max 0.0948 fciksi0.2ksi 0.200ksi

Lt 60dps 2.5ft

ycgp.t ycgp.b




ft.all.rel



Mgr Lt Stti



Pi





1 Ati





Stti




fc.all.rel



Mgr Lt Sbti



Pi





1 Ati





Sbti

23.305 in 28.806 in

Allowable compression before losses (5.9.4.1.1) Allowable tension before losses (Table 5.9.4.1.2-1) Transfer length (AASHTO 5.11.4.1) Prestress eccentricity required for tension
Prestress eccentricity required for compression

A-181

9.

PRESTRESS PROPERTIES (cont'd)

ycgp.req max ycgp.t ycgp.b 23.305in

Required prestress eccentricity at end of beam

yh.brg.req

ycgp.req ybti Ns Nh ysNs Nh

ytop.min 18in

16.852 in

hd 0.4

Minimum distance to harped prestress centroid from bottom of beam at centerline of bearing
Minimum distance between uppermost strand and top of beam
Hold-down point, fraction of the design span length

slopemax

if

dps

=

0.6in 1 12

1 8



0.125

yh.brg

h



ytop.min





0.5Nh 2



1 (2in)

24.5 in

yh.brg min yh.brgyhb slopemaxhdL 24.5in

Maximum slope of an individual strand to limit hold-down force to 4 kips/strand
Set centroid of harped strands as high as possible to minimize release and handling stresses
Verify that slope requirement is satisfied at uppermost strand

CheckEndPrestress if yh.brg t yh.brg.req"OK" "Verify release stresses." "OK"

yp.brg

Nsys Nhyh.brg Ns Nh

12.789 in

Centroid of prestress from bottom at bearing

slopecgp

yp.brg yp hdL

0.021

Slope of prestress centroid within the harping length

ypx(x)

yp slopecgp Lend hdL x if x d Lend hdL
yp otherwise

Distance to center of prestress from the bottom of the beam at any position

A-182

10. PRESTRESS LOSSES

Prestressed losses can be evaluated like regular concrete, in short-term and long-term losses. When the beam is a pretension girder there are instantaneous losses when the beam is shortened upon release of the prestress forces. Time-dependent losses happen when the beam is under creep and shrinkage of the beam concrete, creep and shrinkage o the deck concrete, and the relaxation of prestressed steel. These long term effects are separated into two stages that represent significant events in bridge construction. The first stage is the time between transfer of the prestress forces and placement of the decked beam and the second is the period of time between placement of the deck and the final service load. For decked beams the computation of long-term losses is slightly simplified due to the cross-section not changing between the two stages and the shrinkage term of the deck concrete is eliminated since the deck and beam being cast together. No losses or gains in the steel associated with deck placement after transfer.

AASHTO methods for estimating time-dependent losses: Approximate Estimate (5.9.5.3) Refined Estimate (5.9.5.4)

The Approximate method is based on systems with composite decks and is based on the following assumptions: timing of load application, the cross-section in which the load is applied, and the ratio of dead and live loads to the total load. The conditions for the beams to be fabricated, formed and loaded depend on conditions assumed in the development of the approximate method. The refined method is used to estimate time-dependent losses in the prestressed steel.

Equations 5.9.5.4 are time-dependent and calculate the age-adjustment factors that effect losses using gross section properties.

ti 1 tb 20 td 30 tf 20000

Time (days) between casting and release of prestress Time (days) to barrier casting (exterior girder only) Time (days) to erection of precast section, closure joint pour Time (days) to end of service life

Terms and equations used in the loss calculations:

KL 45

VS Ag 3.857in Peri

ks

max1.45



0.13

VS in

1.0

1.00

khc 1.56 0.008H 1.00

Prestressing steel factor for low-relaxation strands (C5.9.5.4.2c) Volume-to-surface ratio of the precast section
Factor for volume-to-surface ratio (5.4.2.3.2-2)
Humidity factor for creep (5.4.2.3.2-3)

khs 2.00 0.014H 1.02

kf

5 1 fci

ksi

0.676

Humidity factor for shrinkage (5.4.2.3.3-2) Factor for effect of concrete strength (5.4.2.3.2-4)

A-183

10. PRESTRESS LOSSES (cont'd)

ktd(t)

t 61 4 fci t
ksi

t tinit 1.9kskhckfktd(t) tinit 0.118

sh(t) kskhskfktd(t) 0.4810 3

Time development factor (5.4.2.3.2-5)
Creep coefficient (5.4.2.3.2-1) Concrete shrinkage strain (5.4.2.3.3-1)

Time from Transfer to Erection:

epg yp ybg 28.983in

Eccentricity of prestress force with respect to the neutral axis of the gross non-composite beam, positive below the beam neutral axis

fcgp

Pi



1 Ag



epg2 Ixg



Mg

L 2

Ixg



yp



ybg

2.669ksi

Stress in the concrete at the center prestress immediately after transfer

fpt max fpi0.55fpy 187.227ksi

Stress in strands immediately after transfer (5.9.5.4.2c-1)

bid tdti 0.589 bif tf ti 1.282 bid sh td ti 1.490 u 10 4

Creep coefficient at erection due to loading at transfer Creep coefficient at final due to loading at transfer Concrete shrinkage between transfer and erection

Kid

1

1



npi

Aps Ag





1



Agepg2 Ixg





1



0.7bif

0.812

Age-adjusted transformed section coefficient (5.9.5.4.2a-2)

fpSR bidEpKid 3.449ksi

Loss due to beam shrinkage (5.9.5.4.2a-1)

fpCR npifcgpbidKid 7.504ksi

fpR1



fpt



log

KL log

24td 24ti





fpt

fpy



0.551




3

fpSR fpt

fpCR

Kid

1.272ksi

Loss due to creep (5.9.5.4.2b-1)
Loss due to relaxation (C5.9.5.4.2c-1

fpid fpSR fpCR fpR1 12.224ksi

A-184

10. PRESTRESS LOSSES (cont'd)

Time from Erection to Final: epc epg 28.983in

Ac Ag

Ic Ixg

fcd

Mfws

L 2





Mj

L 2





fpid

Scgpf

np

2.12 ksi

bdf tf td 0.858

bif sh tf ti 3.302 u 10 4

bdf bif bid 1.813 u 10 4

Eccentricity of prestress force does not change Section properties remain unchanged
Change in concrete stress at center of prestress due to initial time-dependent losses and superimposed dead load. Deck weight is not included for this design. Creep coefficient at final due to loading at erection
Concrete shrinkage between transfer and final
Concrete shrinkage between erection and final

Kdf

1

1



n

pi

Aps Ac



1



Acepc2 Ic





1

0.7bif

0.812

Age-adjusted transformed section coefficient remains unchanged

fpSD bdfEpKdf 4.196ksi

Loss due to beam shrinkage

fpCD npifcgp bif bid Kdf npfcdbdfKdf 16.588ksi

Loss due to creep

fpR2 fpR1 1.272ksi

Loss due to relaxation

fpSS 0

Loss due to deck shrinkage

fpdf fpSD fpCD fpR2 fpSS 22.056ksi

Prestress Loss Summary fpES 15.273ksi fpLT fpid fpdf 34.28ksi fpTotal fpES fpLT 49.553ksi

fpES fpj

7.5 %

fpLT fpj

16.9 %

fpTotal fpj

24.5 %

fpe fpj fpTotal 152.9ksi

CheckFinalPrestress if fpe d fpe.max"OK" "No Good" "OK"

fp.est 25% Final effective prestress

A-185

11. CONCRETE STRESSES

Concrete Stresses at release, during handling and at final service are computed and compared to approximated values for each stage.

Concrete Stresses at Release

When calculating the stresses at release use the overall beam length due to the beam being supported at each end in the casting bed after prestress forces are transformed.

Define locations for which stresses are to be calculated:

xr

Lg 0


min

Lt

Lend



Lg Lg

max

Lt

Lend



Lg Lg

T 0.1 0.2 0.3 hd 0.5


ir 1 lastxr

Functions for computing beam stresses:

ftop.r(x)

min

x Lt

1



Pi



1 Ati



ybti

ypx(x)



Stti





Mgr(x) Stti

fbot.r(x)

min

x Lt

1



Pi



1 Ati



ybti

ypx(x)
Sbti



Mgr(x) Sbti

Top fiber stress at release Bottom fiber stress at release

4

ftop.r( x) ksi 3

fbot.r( x)
ksi 2
fc.all.rel
ksi 1
ft.all.rel
ksi

0

0

Stresses in Concrete at Release (Half Beam)

Stress (ksi)

1

0

5

10

15

20

25

30

35

40

45

50

x

ft

Distance along Beam (ft)

A-186

11. CONCRETE STRESSES (cont'd) Compare beam stresses to allowable stresses.
ft.all.rel 0.2ksi

Allowable tension at release

fc.all.rel 3.84ksi

Allowable compression at release

TopRelir ftop.r xrir

TopRelT ( 0.000 0.028 0.042 0.044 0.122 0.146 0.117 0.138 )ksi

CheckTopRel if max(TopRel) d fc.all.rel min(TopRel) t ft.all.rel "OK" "No Good" "OK"

BotRelir fbot.r xrir

BotRelT ( 0.000 2.322 2.918 2.736 2.572 2.521 2.583 2.538 )ksi

CheckBotRel if max(BotRel) d fc.all.rel min(BotRel) t ft.all.rel "OK" "No Good" "OK"

Concrete Stresses During Lifting and Transportation

Lifting and transportation stresses can govern over final stresses due to different support locations, dynamic effects that dead load can cause during movement, bending stresses during lifting and superelevation of the roadway in shipping. End diaphragms on both ends are assumed. For prestressing effects, calculate the effective prestressed force losses between transfer and building.

a h 4.125ft

Maximum distance to lift point from bearing line

a' a Lend 6.125ft

Distance to lift point from end of beam

Pdia max WiaWsa 14.7kip

Pm

Pj1


fpES fpid



fpj



1017.5 kip

Approximate abutment weight Effective prestress during lifting and shipping

Define locations for which stresses are to be calculated:

xe

Lg 0


min

Lt

Lend



Lg Lg

max

Lt

Lend



Lg Lg

a' Lg

T hd 0.5


ie 1 lastxe

Compute moment in the girder during lifting with supports at the lift points.

Mlift(x)




wg



wbar 2

x2





Pdia

x

if

x d a'


Mgr(x) Mgr(a')

wg



wbar 2

(a')2





Pdia

a'

otherwise

A-187

11. CONCRETE STRESSES (cont'd) Functions for computing beam stresses:

ftop.lift(x)

min

x Lt

1



Pm



1 Atf



ybtf

ypx(x)



Sttf





Mlift(x) Sttf

ftop.DIM.inc(x)

min

x Lt

1



Pm



1 Atf



ybtf

ypx(x)



Sttf





Mlift(x) (1 Sttf



DIM)

ftop.DIM.dec(x)

min

x Lt

1



Pm



1 Atf



ybtf

ypx(x)



Sttf





Mlift(x) (1 Sttf



DIM)

Top fiber stress during lifting
Top fiber stress during lifting, impact increasing dead load
Top fiber stress during lifting, impact decreasing dead load

TopLift1ie TopLift2ie TopLift3ie

ftop.lift xeie ftop.DIM.inc xeie ftop.DIM.dec xeie

TopLift1T ( 0.000 0.107 0.140 0.231 0.104 0.082 )ksi TopLift2T ( 0.000 0.113 0.148 0.252 0.014 0.044 )ksi TopLift3T ( 0.000 0.101 0.133 0.210 0.223 0.209 )ksi

fbot.lift(x)

min

x Lt

1



Pm



1 Atf



ybtf

ypx(x)



Sbtf





Mlift(x) Sbtf

fbot.DIM.inc(x)

min

x Lt

1



Pm



1 Atf



ybtf

ypx(x)



Sbtf





Mlift(x) (1 Sbtf



DIM)

fbot.DIM.dec(x)

min

x Lt

1



Pm



1 Atf



ybtf

ypx(x)



Sbtf





Mlift(x) (1 Sbtf



DIM)

Bottom fiber stress during lifting
Bottom fiber stress during lifting, impact increasing dead load
Bottom fiber stress during lifting, impact decreasing dead load

BotLift1ie BotLift2ie BotLift3ie

fbot.lift xeie fbot.DIM.inc xeie fbot.DIM.dec xeie

BotLift1T ( 0.000 2.360 2.965 3.156 2.888 2.842 )ksi BotLift2T ( 0.000 2.372 2.980 3.201 2.638 2.574 )ksi BotLift3T ( 0.000 2.348 2.949 3.112 3.139 3.109 )ksi

Allowable stresses during handling:
fcm fc.erec fc 7.2ksi
fc.all.erec 0.6fcm 4.32ksi
ft.all.erec ft.erec fcm 0.429ksi

Assumed concrete strength when handling operations begin Allowable compression during lifting and shipping Allowable tension during lifting and shipping

A-188

11. CONCRETE STRESSES (cont'd) Stresses in Concrete During Lifting (Half Beam)

Stress (ksi)

ftop.lift( x) ksi

ftop.DIM.inc(x) 4 ksi

ftop.DIM.dec( x) ksi

fbot.lift( x) ksi

fbot.DIM.inc ( x)

ksi

2

fbot.DIM.dec( x) ksi

fc.all.erec ksi

ft.all.erec
ksi 0
0

0

5

10

15

20

25

30

35

40

45

50

x

ft

Distance along Beam (ft)

Compare beam stresses to allowable stresses.

TopLiftMaxie max TopLift1ie TopLift2ie TopLift3ie

TopLiftMaxT ( 0 0.101 0.133 0.21 0.014 0.044 )ksi

TopLiftMinie min TopLift1ie TopLift2ie TopLift3ie

TopLiftMinT ( 0 0.113 0.148 0.252 0.223 0.209 )ks

CheckTopLift if max(TopLiftMax) d fc.all.erec min(TopLiftMin) t ft.all.erec "OK" "No Good" "OK"

BotLiftMaxie max BotLift1ie BotLift2ie BotLift3ie

BotLiftMaxT ( 0 2.372 2.98 3.201 3.139 3.109 )ksi

BotLiftMinie min BotLift1ie BotLift2ie BotLift3ie

BotLiftMinT ( 0 2.348 2.949 3.112 2.638 2.574 )ksi

CheckBotLift if max(BotLiftMax) d fc.all.erec min(BotLiftMin) t ft.all.erec "OK" "No Good" "OK"

A-189

11. CONCRETE STRESSES (cont'd)

Concrete Stresses at Final

Stresses are calculated using design span length. The top flange compression and bottom flange under tension are computed at Service I and Service III states.

fc.all.ser1 0.4fc 3.2ksi fc.all.ser2 0.6fc 4.8ksi

Allowable compression due to effective prestress and dead load (Table 5.9.4.2.1-1)
Allowable compression due to effective prestress, permanent load, and transient loads, as well as stresses during shipping and handling (Table 5.9.4.2.1-1)

ft.all.ser 0ksi

Allowable tension (computed previously)

Pe fpeAps 889.2kip

Effective prestress after all losses

Compute stresses at midspan and compare to allowable values.

ftop.ser1(x)

Lend min
Lt

x

1




Pe



1 Atf



ybtf

ypx(x)



Sttf





Mg

x Lend Stti

Mbar(x) Mfws(x) Mj(x) Sttf

ftop.ser2(x)

Lend min
Lt

x

1




Pe



1 Atf



ybtf

ypx(x)



Sttf





Mg

x Lend Stti

Mbar(x) Mfws(x) Mj(x) Mll(x) Sttf

fbot.ser(x)

Lend min
Lt

x

1




Pe



1 Atf



ybtf

ypx(x)



Sbtf





Mg

x Lend Sbti

Mbar(x) Mfws(x) Mj(x) 0.8Mll(x) Sbtf

Stresses in Concrete at Service (Half Beam) 6

ftop.ser1( x) ksi
ftop.ser2( x) ksi 4

Stress (ksi)

fbot.ser( x) ksi
ft.all.ser ksi 2
fc.all.ser1 ksi
fc.all.ser2 ksi 0

0

5

10

15

20

25

30

35

40

45

50

x

ft

Distance along Beam (ft)

A-190

11. CONCRETE STRESSES (cont'd)

Compare beam stresses to allowable stresses.

xs

L Lt L

0.1

0.15

0.2

0.25

0.3

0.35

hd

0.45

0.5 T

is 1 lastxs

TopSer1is ftop.ser1 xsis TopSer2is ftop.ser2 xsis

TopSer1T TopSer2T

( 0.064 0.216 0.304 0.374 0.425 0.459 0.474 0.471 0.471 0.474 )ksi ( 0.164 0.508 0.716 0.887 1.021 1.119 1.184 1.218 1.236 1.240 )ksi

CheckCompSerI if max(TopSer1) d fc.all.ser1 max(TopSer2) d fc.all.ser2 "OK" "No Good" "OK"

BotSeris fbot.ser xsis

BotSerT ( 2.028 1.381 0.993 0.675 0.426 0.246 0.131 0.075 0.044 0.036 )ksi

CheckTenSerIII if min(BotSer) t ft.all.ser"OK" "No Good" "OK"

12. FLEXURAL STRENGTH

Confirm flexural resistance at Strength Limit State. Calculate Factored moment at midspan during Strength I load combination. Compare this to factored resistance in AASHTO LRFD 5.7.3.

MDC(x) Mg(x) Mbar(x) Mj(x)

Self weight of components

MDW(x) Mfws(x)

Weight of future wearing surface

MLL(x) Mll(x)

Live load

MStrI(x) 1.25MDC(x) 1.5MDW(x) 1.75MLL(x)

Factored design moment

For minimum reinforcement check, per 5.7.3.3.2

fcpe

Pe



1 Ag



ycgp
Sbg

3.551ksi

Mcr fr.cm fcpe Sbg 3541kipft

Mu(x) max MStrI(x) min 1.33MStrI(x) 1.2Mcr

Concrete compression at extreme fiber due to effective prestress Cracking moment (5.7.3.3.2-1)
Design moment

A-191

12. FLEXURAL STRENGTH (cont'd)

Compute factored flexural resistance.

1

max0.650.85 0.05 fc 4



ksi

k

21.04



fpy

0.28



fpu

dp(x) h ypx x Lend

0.65 dp(X)

44.921 in

hf d7 8in

btaper

b6 b5 2

16 in

htaper d5 2in

a(x) c(x)

Apsfpu

0.85fcbf



k 1



Aps



fpu dp(x)



a(x)

1

a(X) 2.524in c(X) 3.883in

CheckTC

if dcp((XX))

d



.003 .003 .005



"OK"

"NG"

"OK"

Stress block factor (5.7.2.2)
Tendon type factor (5.7.3.1.1-2) Distance from compression fiber to prestress centroid Structural flange thickness Average width of taper at bottom of flange Depth of taper at bottom of flange Depth of equivalent stress block for rectangular section
Neutral axis location
Tension-controlled section check (midspan)

f

min1.0max0.750.583 0.25 dp(X) 1





c(X)

1.00

Resistance factor for prestressed concrete (5.5.4.2)

fps

fpu1



k

c(X) dp(X)



263.5ksi

Average stress in the prestressing steel (5.7.3.1.1-1)

Ld

1.6 ksi





fps



2 3



fpe



dps

10.767 ft

Bonded strand devlepment length (5.11.4.2-1)

fpx(x)

fpe x Lend
Lt

if x d Lt Lend

Stress in prestressing steel along the length for bonded strand (5.11.4.2)

fpe

x

Lend Ld Lt

Lt

fps



fpe

if Lt Lend x d Ld Lend

fps otherwise

Mr(x)

fApsfpx(x)dp(x)



a(x) 2



Flexure resistance along the length

A-192

12. FLEXURAL STRENGTH (cont'd)

xmom

L 0.01

Lt Lend L

Ld Lend L

hd

0.5 T

Mrximom Mr xmomimom

Muximom Mu xmomimom

imom 1 last xmom

DCmom

Mux Mrx

max DCmom 0.798

CheckMom if max DCmom d 1.0"OK" "No Good"

"OK"

Demand-Capacity ratio for moment Flexure resistance check

Design Moment and Flexure Resistance (Half Beam)

Moment (kipft)

MStrI( x) kip ft

1.2 Mcr kip ft

4000

1.33 MStrI( x) kip ft

Mu( x) kip ft

2000

Mr( x) kip ft

0

0

5

10

15

20

25

30

35

40

45

50

x

ft

Distance along Beam (ft)

A-193

13. SHEAR STRENGTH

Shear Resistance

Use Strength I load combination to calculate factored shear at the critical shear section and at tenth points along the span. Compare it to factored resistance in AASHTO LRFD 5.8.

VDC(x) Vg(x) Vbar(x) Vj(x)

Self weight of components

VDW(x) Vfws(x)

Weight of future wearing surface

VLL(x) Vll(x)

Live load

Vu(x) 1.25VDC(x) 1.5VDW(x) 1.75VLL(x)

Factored design shear

v 0.90

Resistance factor for shear in normal weight concrete (AASHTO LRFD 5.5.4.2)

dend h ypx Lend 36.711in

Depth to steel centroid at bearing

dv min 0.9dend0.72h 33.039in

Effective shear depth lower limit at end

Vp(x)

Peslopecgp

x

Lend Lt

if x d Lt Lend

Peslopecgp if Lt Lend x d hdL

0 otherwise

bv b3 6in

vu(x)

Vu(x) vVp(x) vbvdv

Mushr(x) max MStrI(x) Vu(x) Vp(x) dv

fpo 0.7fpu 189ksi

Vertical component of effective prestress force
Web thickness Shear stress on concrete (5.8.2.9-1) Factored moment for shear Stress in prestressing steel due to locked-in strain after casting concrete

s(x)



Mu(x)

max0.410 3 dv



Vu(x) Vp(x) EpAps



Aps

fpo



Steel strain at the centroid of the prestressing

steel

(x)

4.8

1 750s(x)

(x) 29 3500s(x) deg

Shear resistance parameter Principal compressive stress angle

Vc(x)

0.0316ksi(x)

fc ksi



bv

dv

Concrete contribution to total shear resistance

A-194

13. SHEAR STRENGTH (cont'd)

90deg

Angle of inclination of transverse reinforcement

Av ( 1.02 0.62 0.62 0.62 0.31 )Tin2

sv ( 3 6 6 12 12 )Tin

Transverse reinforcement area and spacing provided

xv ( 0 0.25h 1.5h 0.3L 0.5L 0.6L )T

xvT ( 0 1.031 6.187 24 40 48 )ft

Avs(x) for i 1 last Av

out m Avi svi

if xvi d x d xvi1

.

out

Vs(x) Avs(x)fydv(cot((x)) cot())sin()

Steel contribution to total shear resistance

Vr(x) v Vc(x) Vs(x) Vp(x)

Factored shear resistance

xshr

for i 1 100

outi

m

i

0.5L 100

out

ishr 1 last xshr

Vuxishr Vu xshrishr

Vrxishr Vr xshrishr

DCshr

Vux Vrx

max DCshr 0.822

CheckShear if max DCshr d 1.0"OK" "No Good" "OK" Shear resistance check

Shear (kips)

Vu(x) 400 kip
Vr(x) 200 kip
0 0

Design Shear and Resistance (Half Beam)

5

10

15

20

25

30

35

40

45

50

x

ft

Distance along Beam (ft)

A-195

13. SHEAR STRENGTH (cont'd)

Longitudinal Reinforcement

Al.req(x)

a1 m

MStrI(x)

ffpx(x)dp(x)



a(x) 2



a2

m

Vu(x)



v



0.5Vs(x)



Vp( x) cot( ( x) )


fpx(x)

a3 m

Mushr(x) dvf




Vu(x) v



Vp(x)

0.5Vs(x)cot((x))


fpx(x)

min(a1a2) if x d dv 5in

min(a1a3) otherwise

Longitudinal reinforcement required for shear (5.8.3.5)

As.add 0.40in2

Ld.add 18.67ft

Additional longitudinal steel and developed length from end of beam

Al.prov(x)

if x Ld.add LendAs.add0

ApNs

x

Lend Ld

if x d Ld Lend

ApNs

if

Ld



Lend



x

d

yh.brg 0.5h slopecgp



0.5Nh 2



1 (2in)cot

slopecgp

Ap Nh Ns otherwise

Steel Area (in2)

6 Al.req( x)
in2 4
Al.prov( x) 2
in2
0 0

Longitudinal Reinforcement Required and Provided (Half Beam)

5

10

15

20

25

30

35

40

45

50

x

ft

Distance along Beam (ft)

Al.reqishr Al.req xshrishr

Al.provishr Al.prov xshrishr

DClong

Al.req Al.prov

max DClong 1.268

CheckLong if max DClong d 1.0"OK" "No Good" "No Good"

Longitudinal reinforcement check

A-196

14. SPLITTING RESISTANCE Splitting Resistance Checking splitting by zone of transverse reinforcement. Defined in Shear Strength section.

As

Av1xv2 sv1

4.208in2

fs 20ksi

Pr fsAs 84.2kip

Pr.min 0.04Pj 47.1kip

CheckSplit if Pr t Pr.min"OK" "No Good" "OK"

Limiting stress in steel for crack control (5.10.10.1) Splitting resistance provided (5.10.10.1-1) Minimum splitting resistance required Splitting resistance check

15. CAMBER AND DEFLECTIONS Calculate Deflections due to different weights, joints, and future wearings.

ps

Pi





ycgp

Lg2



ybg



yp.brg



hdL



Lend

2

EciIxg 8

6



2.246in Deflection due to prestress at release

gr

5 wgLg4 384 EciIxg

1.006in

Deflection due to self-weight at release

bar

5 wbarLg4 384 EcIxg

0.286in

Deflection due to barrier weight

j

5 wjL4 if (BeamLoc = 0 1 0.5) 384 EcIxg

0.014in

2

Deflection due to longitudinal joint

fws

5



wfwsL4 if BeamLoc

=

S 0 1



Wb

384 EcIxg

S

0.088in

Deflection due to future wearing surface

tbar 20

Age at which barrier is assumed to be cast

T ti 7 14 21 28 60 120 240 T

Concrete ages at which camber is computed

A-197

15. CAMBER AND DEFLECTIONS (cont'd)
cr1(t) t titi gr ps

cr2(t) t titi tbar titi gr ps t tbartbar bar

cr3(t) t titi td titi gr ps t tbartbar td tbartbar bar t tdtd j

cr(t) Defl(t)

cr1(t) if t d tbar
cr1 tbar cr2(t) if tbar t d td cr1 tbar cr2 td cr3(t) if t ! td
gr ps cr1(t) if t d tbar gr ps cr1 tbar bar cr2(t) if tbar t d td gr ps cr1 tbar bar cr2 td j cr3(t) if t ! td

C for j 1 last(T)
outj m Defl Tj
out

CT ( 1.24 1.471 1.668 1.522 1.595 1.793 1.968 2.094 2.262 )in

Deflection (in)

3
cr( t) in 2
Defl( t) 1
in

60-Day Deflection at Midspan

0

0

20

40

60

t

Age of Concrete (days)

Deflection (in)

3
cr( t) in 2
Defl( t) 1
in
0 0

Long-term Deflection at Midspan

500

1000

t

Age of Concrete (days)

1500

2000

A-198

16. NEGATIVE MOMENT FLEXURAL STRENGTH
Calculate factored moment that must be resisted across the interior pier and find required steel to be developed in the top flange.

Negative Live Load Moment
Compute the negative moment over the interior support due to the design live load load, in accordance with AASHTO LRFD 3.6.1.3.1.

Live Load Truck and Truck Train Moment Calculations

min Mtruck 1037kipft

min Mtrain 2038kipft

Mneg.lane

wlaneL2 2

2048kipft

Maximum negative moment due to a single truck
Maximum negative moment due to two trucks in a single lane
Negative moment due to lane load on adjacent spans

Mneg.truck Mneg.lane (1 IM)min Mtruck 3427kipft

Live load negative moment for single truck

Mneg.train 0.9Mneg.lane (1 IM)min Mtrain 4282kipft

Live load negative moment for two trucks in a single lane

MHL93.neg min Mneg.truck Mneg.train 4282kipft

Design negative live load moment, per design lane

Mll.neg.i MHL93.neggmint 2720kipft Mll.neg.e MHL93.neggmext 2832kipft
MLL.neg if BeamLoc = 1 Mll.neg.eMll.neg.i 2832kipft

Design negative live load moment at interior beam
Design negative live load moment at exterior beam
Design negative live load moment

Factored Negative Design Moment

Dead load applied to the continuity section at interior supports is limited to the future overlay.

MDW.neg

wfwsL2 2

635kipft

Mu.neg.StrI 1.5MDW.neg 1.75MLL.neg 5908kipft

Superimposed dead load resisted by continuity section
Strength Limit State

Mu.neg.StrI 1.0MDW.neg 1.0MLL.neg 3467kipft

Service Limit State

A-199

16. NEGATIVE MOMENT FLEXURAL STRENGTH (cont'd)

Reinforcing Steel Requirement in the Top Flange for Strength

f 0.90

bc b1 26in
dnms h tsac 0.5 tflange tsac

44.5 in

Reduction factor for strength in tensioncontrolled reinforced concrete (5.5.4.2)
Width of compression block at bottom flange
Distance to centroid of negative moment steel, taken at mid-depth of top flange

Ru

Mu.neg.StrI

f



bcd

2
nms

0.898ksi

m

fy

8.824

0.85fc

req

1

1



m

1



2

m

Ru



fy

0.0161

Anms.req reqbcdnms 18.638in2

As.long.t 2.0in2

As.long.b 2.0in2

Abar 0.44in2

Anms.t

2 3

Anms.req



As.long.t

nbar.t

Anms.t

ceil



Abar

24

10.425 in2

Anms.b

1 3

Anms.req



As.long.b

nbar.b

Anms.b

ceil



Abar

10

4.213in2

sbar.top

S Wj 6in nbar.t 1

3.62 in

As.nms nbar.t nbar.b Abar As.long.t As.long.b

18.96in2

a As.nmsfy 6.434in 0.85fcbc

Mr.neg

fAs.nmsfydnms



a 2



3522kipft

DCneg.mom

Mu.neg.StrI Mr.neg

0.984

CheckNegMom if DCneg.mom d 1.0"OK" "No Good"

"OK"

Factored load, in terms of stress in concrete at depth of steel, for computing steel requirement Steel-to-concrete strength ratio
Required negative moment steel ratio
Required negative moment steel in top flange Full-length longitudinal reinforcement to be made continuous across joint Additional negative moment reinforcing bar area Additional reinforcement area required in the top mat (2/3 of total) Additional bars required in the top mat
Additional reinforcement area required in the bottom mat Additional bars required in the top mat
Spacing of bars in top mat
Total reinforcing steel provided over pier
Depth of compression block
Factored flexural resistance at interior pier
Negative flexure resistance check

A-200

File Name: Prestressed Concrete Girder-60ft.xmcd

DECKED PRECAST PRESTRESSED CONCRETE GIRDER DESIGN FOR ABC

Unit Definition:

kcf { kipft 3

This example is for the design of a superstructure system that can be used for rapid bridge replacement in an Accelerated Bridge Construction (ABC) application. The following calculations are intended to provide the designer guidance in developing a similar design with regard to design considerationS characteristic of this type of construction, and they shall not be considered fully exhaustive.
Overall Width, W

Barrier Width, Wb

Joint Width, Wj

Roadway Width, Wr Slope, CS

S Wj 2


Beam Spacing, S TYPICAL SECTION THROUGH SPAN

Lend Bridge Geometry:

Design Span Length, L Girder Length, Lg

GIRDER ELEVATION

L 60ft

W 63ft

Smax 8ft

Ng

W Wj

ceil



Smax

8

S W Wj 7.938ft Ng

Lend 2ft Wb 1.5ft Wj 0.5ft

skew 0deg

Minimum number of girders in cross-section

Girder spacing

A-201

ORDER OF CALCULATIONS

1. Introduction 2. Design Philosophy 3. Design Criteria 4. Beam Section 5. Material Properties 6. Permanent Loads 7. Precast Lifting Weight 8. Live Load 9. Prestress Properties 10. Prestress Losses 11. Concrete Stresses 12. Flexural Strength 13. Shear Strength 14. Splitting Resistance 15. Camber and Deflections 16. Negative Moment Flexural Strength

1.

INTRODUCTION

The bridge that is designed in this example consists of precast prestressed concrete girders with a top flange equal to the beam spacing, so the top flange will be the riding surface of the designed bridge. The purpose for these girders is to rapidly construct the bridge by providing a precast deck on the girders, which eliminates cast-in-place decks in the field and improves safety.

The concepts used in this example have been taken from on-going research, which focuses on the benefits of decked precast beams and promoting widespread acceptance from transportation and construction industries. The cross-section is adapted from the optimized girder sections recommended by NCHRP Project No. 12-69, Design and Construction Guidelines for Long-Span Decked Precast, Prestressed Concrete Girder Bridges. The girder design has not taken into account the option to re-deck due to the final re-decked girder, without additional prestressed, having a shorter life span. Use of stainless steal rebar and the application of a future membrane can get ride of the need to replace the deck. This case is included in "re-deckability".

The bridge used in this example is a general design of a typical bridge in Georgia. The calculations can be modified for single-span and multiple-span bridges due to the beam design moments are not reduced for continuity at intermediate supports (continuity details are not shown in this example). The cross-section consists of a four-lane roadway with normal crown, with standard shoulder lengths and barrier walls. The precast prestressed concrete girder has been uniformly designed to simplify bearing details. The girder flanges are 9'' at the tips, imitating a 8'' slab with a '' allowable wear and another '' for smoothness and profile adjustments.

This example is intended to illustrate design aspect specific to precast prestressed concrete girders used for ABC application. Girders with uncommon cross-sections, high self-weight, or unconventional load application create major concerns and more detailed calculations must be done.

A-202

2.

DESIGN PHILOSOPHY

The geometry of the section is based on GDOT standards and general bridges across the state of Georgia. Depth variations are dependent on the construction company but must maintain the shapes of the top flange and the bottom bulb.

Concrete strengths can vary but are mostly between 6 ksi and 10 ksi. For the purpose of these calculations the concrete with a 28-day minimum compressive strength of 8 ksi is used. Due to its casting sequence this beam is unable to take advantage of composite sequences along with tension at the bottom of the beam at the service limit state being limited. This is further discussed in section 4 along with end region stresses being critical. Therefore the minimum concrete strength at release must be 80 percent of the 28-day compressive strength, which increases the allowable stresses at the top and bottom of the section. The prestressed steel can also be optimized to minimize stresses at the end region.

The prestressed steel is arranged in a draped, or harped, pattern to maximize the midspan effectiveness while it minimizes the failure at the end of the beam where is concrete is easily overstressed due to the lack of dead load acting on the beam. The strand group is optimized at the midspan by bundling the strands between hold-points, maximizing the stiffness of the strand group. The number and deflection angles are depended on the type of single strands you are using for the girder. In longer span cases the concrete at the end of the girder will be too large and will debond. Without harped strands it is unlikely to reduce stresses to the allowable limit, since harped strands are required this method of stress relief will be used without debonding for long spans.

3.

DESIGN CRITERIA

Criteria has been selected to govern the design of these concrete girders while following provisions set by AASHTO, GDOT design specifications, as well as criteria of past projects and current research related to ABC and decked precast sections. A summary of the limiting design values are categorized as section constraints, prestress limits, and concrete limits.

Section Constraints:

Wpc.max 200kip
Smax 8ft Prestress Limits:

Upper limit on the weight of the entire precast element, based on common lifting and transport capabilities without significantly increasing time and/or cost due to unconventional equipment or permits
Upper limit on girder spacing and, therefore, girder flange width (defined on first page)

Fhd.single 4kip

Maximum hold-down force for a single strand

Fhd.group 48kip

Maximum hold-down force for the group of harped strands

Stress limits in the prestressing steel immediately prior to prestress and at the service limit state after all losses are as prescribed by AASHTO LRFD.

A-203

3.

DESIGN CRITERIA (cont'd)

Concrete Limits:

Allowable concrete stresses meet standards set by AASHTO LRFD with one exception that at Service III Limit State, allowable bottom fiber tension when camber leveling forces are to be neglected, regardless of exposure, are to be 0-ksi. Minimum strength of concrete at release is 80 percent of the 28-day minimum compressive strength (f-ksi).

ft.all.ser 0ksi

Allowable bottom fiber tension at the Service III Limit State, when camber leveling forces are to be neglected, regardless of exposure

As previously mentioned, release concrete strength is specified as 80 percent of the minimum 28-day compressive strength to maximize allowable stresses in the end region of beam at release.

fc.rel(f ) 0.80f

Minimum strength of concrete at release

Due to various lifting and transportation conditions, stresses in the concrete need to be considered. A "no cracking" approach is used for allowable tension due to reduced lateral stability after cracking. Assuming the girders will be lifted before the 28-day minimum strength is attained, the strength of concrete during lifting and transportation is assumed to be 90 percent of the 28-day minimum compressive strength. A dynamic dead load allowance of 30 percent is used for compression during handling. A factor of safety (FS) of 1.5 is used against cracking during handling.

DIM 30%

Dynamic dead load allowance

fc.erec(f ) 0.90f

FSc 1.5

ft.erec(f )

0.24 f ksi FSc

Assumed attained concrete strength during lifting and transportation Factor of safety against cracking during lifting transportation Allowable tension in concrete during lifting and transportation to avoid cracking

A-204

4.

BEAM SECTION

Use trapezoidal areas to define the cross-section. The flange width is defined as the beam spacing less the width of the longitudinal closure joint to reflect pre-erection conditions. Live load can be conservatively applied to this section, as well.

h 45in

Beam section depth

tflange 9in tsac 1in

Flange thickness at tip

Total sacrificial depth for grinding and wear

y

b1 26in b2 26in b3 6in b4 6in b5 10in b6 42in b7 89.25in

b2 26in b3 6in b4 6in b5 10in b6 42in b7 S Wj b8 S Wj

d3 h tsac d

Gross Section Properties

d1 6in d2 4.5in
d4 2in d5 2in d6 0in d7 tflange tsac
d3 21.5in

b n+1

bn

b n-1 bn-2

d n-2

b3 b2
b1

d2
d1 x

TYPICALGIRDERSECTIONCOMPR ISED OFnTRAPEZOIDALR EGIONS

dn dn-1

bf 89.25in Ag 1139in2 Ixg 241240in4
ytg 13.544in Stg 17811.7in3 Iyg 487677in4

ybg 30.456in Sbg 7920.9in3

Precast girder flange width Cross-sectional area (does not include sacrifical thickness) Moment of inertia (does not include sacrificial thickness) Top and bottom fiber distances from neutal axis (positive up) Top and bottom section moduli Weak-axis moment of inertia

GIRDER SECTION PLOT (N.T.S.) 47

40.875

34.75

28.625

22.5

16.375

10.25

4.125

2

50 40 30 20 10 0

10 20 30 40

50

A-205

5.

MATERIAL PROPERTIES

These properties are standard (US units) values with equations that can be found in AASHTO LRFD Bridge Design Specifications.

Concrete: fc 8ksi
fci fc.rel fc

6.4 ksi

c .150kcf

K1 1.0

Eci

33000

K1



c kcf

1.5

fciksi

4850 ksi

Ec

33000K1



c kcf



1.5

fcksi

5422 ksi

Minimum 28-day compressive strength of concrete Minimum strength of concrete at release Unit weight of concrete Correction factor for standard aggregate (5.4.2.4) Modulus of elasticity at release (5.4.2.4-1)
Modulus of elasticity (5.4.2.4-1)

fr.cm 0.37 fcksi 1.047ksi fr.cd 0.24 fcksi 0.679ksi H 70

Modulus of rupture for cracking moment (5.4.2.6) Modulus of rupture for camber and deflection (5.4.2.6) Relative humidity (5.4.2.3)

Prestressing Steel:

fpu 270ksi

fpy 0.9fpu 243ksi

fpbt.max 0.75fpu 202.5ksi

fpe.max 0.80fpy 194.4ksi

Ep 28500ksi

dps 0.5in Ap 0.153in2

Nps.max 40

npi

Ep Eci

5.9

np

Ep Ec

5.3

Mild Steel:

Ultimate tensile strength Yield strength, low-relaxation strand (Table 5.4.4.1-1) Maximum stress in steel immediately prior to transfer Maximum stress in steel after all losses Modulus of elasticity (5.4.4.2) Strand diameter Strand area Maximum number of strands in section Modular ratio at release
Modular ratio

A-206

fy 60ksi Es 29000ksi

Specified minimum yield strength Modulus of elasticity (5.4.3.2)

A-207

6.

PERMANENT LOADS

Permanent loads or dead loads that must be considered are self-weight, diaphragms, barriers, and future wearing surface. The barrier can be cast to the beam before it is taken on sight or attached to the bridge after the joints have reached sufficient strength. Distribution of the barriers weight should be established once you decide when it would be attached to the bridge. For this example the barrier has been cast on the exterior girder in the casting yard, before shipping but after release of prestresses. Due to this the dead load is increased on the exterior girders but it eliminates the time-consuming task that would have been completed in the field.

BeamLoc 1

Location of beam within the cross-section (0 - Interior, 1 - Exterior)

Load at Release: c.DL .155kcf
Ag.DL Ag tsac S Wj 1228.25in2

Concrete density used for weight calculations Area used for weight calculations, including sacrificial thickness

wg Ag.DLc.DL 1.322klf

Uniform load due to self-weight, including sacrificial thickness

Lg L 2Lend 64ft

Mgr(x)

wgx 2

Lg



x

Vgr(x)

wg



Lg 2



x

Span length at release Moment due to beam self-weight (supported at ends) Shear due to beam self-weight (supported at ends)

Load at Erection:

Mg(x)

wgx (L x) 2

Vg(x)

wg



L 2



x

Moment due to beam self-weight Shear due to beam self-weight

wbar 0.430klf

Uniform load due to barrier weight, exterior beams only

wbar if BeamLoc = 1 wbar0 0.43klf Redfine to 0 if interior beam (BeamLoc = 0)

Mbar(x)

wbarx (L x) 2

Vbar(x)

wbar



L 2



x

Moment due to beam self-weight Shear due to beam self-weight

A-208

6.

PERMANENT LOADS (cont'd)

Load at Service:

pfws 25psf

wfws pfwsS 0.198klf

Mfws(x)

wfwsx (L x) 2

Vfws(x)

wfws



L 2



x

wj Wjd7c.DL 0.052klf

Mj(x)

wjx (L x) 2

Vj(x)

wj



L 2



x

Assumed weight of future wearing surface Uniform load due to future wearing surface Moment due to future wearing surface Shear due to future wearing surface
Uniform load due to weight of longitudinal closure joint Moment due to longitudinal closure joint Shear due to longitudinal closure joint

A-209

7.

PRECAST LIFTING WEIGHT

For Accelerated Bridge Construction the beams are casted in a factory and transported to the job site. When they arrive at the site they must be lifted and put into place. When designing we have to consider the weight of each slab to insure safety and design for possible cracking.

Precast Superstructure
Wg wg wbar Lg 112.1kip

Substructure Precast with Superstructure

Lcorb 1ft

Bcorb bf

bf 89.25in

Dcorb 1.5ft Vcorb LcorbBcorbDcorb

11.16ft3

Precast girder, including barrier if necessary
Length of approach slab corbel Width of corbel cast with girder Average depth of corbel Volume of corbel

Lia 2.167ft

Length of integral abutment

Lgia 1.167ft

Length of girder embedded in integral abutment

Bia S Wj 7.438ft

Width of integral abutment cast with girder

Dia h 4in 49in
Via Vcorb LiaBiaDia Ag tflangebf Lgia

74.25ft3

Depth of integral abutment Volume of integral abutment cast with girder

Wia Viac 11kip

Weight of integral abutment cast with girder

Lsa 2.167ft

Length of semi-integral abutment

Lgsa 4in

Length of girder embedded in semi-integral abutment

Bsa S Wj 7.438ft

Width of semi-integral abutment cast with girder

Dsa h 16in 61in
Vsa Vcorb LsaBsaDsa Ag tflangebf Lgsa

Depth of semi-integral abutment 92.31ft3 Volume of semi-integral abutment cast with girder

Wsa Vsac 14kip

Weight of semi-integral abutment cast with girder

A-210

Semi-Integral Abutment Backwall

Integral Abutment Backwall

A-211

8.

LIVE LOAD

When considering Live Loads you must refer to the vertical load section HL-93 in the AASHTO manual. If the project you are working on requires the bridge to support construction loads at any stage, these loads must be considered separately and applied. The longitudinal joints are designed for full moment connections so the beams will act as a unit when sufficiently connected. The distribution factors are then computed for cross-section type "j" (defined in AASHTO 4.6.2.2). When calculating the stiffness parameter, the constant- depth region at the top flange is treated like the slab and the remaining area of the beam will be considered a non-composite beam.

Definitions:

Ibb

=

Abb

=

ybb

=

ts

=

moment of inertia of section below the top flange area of beam section below the top flange distance of top fiber below the top flange from neutral axis thickness of slab not including sacrificial thickness

Distribution Factors for Moment: From Table 4.6.2.2.2b-1 for moment in interior girders,

Ibb 63137in4

Abb 425in2

eg

h





tsac



ts 2



ybb

25.578 in

Kg 1.0Ibb Abbeg2 341179in4

Moment of inertia of section below the top flange Area of beam section below the top flange Distance between c.g.'s of beam and flange Longitudinal stiffness parameter (Eqn. 4.6.2.2.1-1)

Verify this girder design is within the range of applicability for Table 4.6.2.2.2b-1.
CheckMint if (S d 16ft)(S t 3.5ft)ts t 4.5in ts d 12.0in (L t 20ft)(L d 240ft) "OK" "No Good" CheckMint if (CheckMint = "OK" )Ng t 4 Kg t 10000in4Kg d 7000000in4 "OK" "No Good"
CheckMint "OK"

gmint1

0.06





S 14

ft



0.4



S L



0.3



Kg 0.1 Lts3

0.491

gmint2

0.075





S 9.5ft



0.6

S L



0.2

Kg 0.1 Lts3

0.669

gmint max gmint1gmint2 0.669

Single loaded lane Two or more loaded lanes Distribution factor for moment at interior beams

A-212

8.

LIVE LOAD (cont'd)

From Table 4.6.2.2.2d-1 for moment in exterior girders,

de

S 2



Wb

29.625 in

Distance from centerline of exterior beam to edge of curb or barrier

CheckMext if de t 1ft de d 5.5ft Ng t 4 "OK" "No Good" "OK"

For a single loaded lane, use the Lever Rule.

gmext1

S 0.5bf Wb 5ft S

0.65

em

0.77 de 9.1ft

1.041

gmext2 emgmint 0.697

gmext max gmext1gmext2 0.697

Single loaded lane Correction factor for moment (Table 4.6.2.2.2d-1) Two or more loaded lanes Distribution factor for moment at exterior beams

Distribution Factors for Shear: From Table 4.6.2.2.3a-1 for shear in interior girders,
Verify this girder design is within the range of applicability for Table 4.6.2.2.3a-1.
CheckVint if (S d 16ft)(S t 3.5ft)ts t 4.5in ts d 12.0in (L t 20ft)(L d 240ft) "OK" "No Good" CheckVint if (CheckMint = "OK" )Ng t 4 "OK" "No Good"
CheckVint "OK"

gvint1

0.36





S 25ft



0.678

gvint2

0.2





S 12ft







S 35ft



2.0

0.81

gvint max gvint1 gvint2 0.81

Single loaded lane Two or more loaded lanes Distribution factor for shear at interior beams

A-213

8.

LIVE LOAD (cont'd)

From Table 4.6.2.2.3b-1 for shear in exterior girders,

For a single loaded lane, use the Lever Rule.

CheckVext if de t 1ft de d 5.5ft Ng t 4 "OK" "No Good" "OK"

g1

S 0.5bf Wb 5ft S

0.65

ev

0.6 de 10ft

0.847

g2 evgvint 0.686

gvext max g1g2 0.686

Single loaded lane (same as for moment) Correction factor for shear (Table 4.6.2.2.3b-1) Two or more loaded lanes Distribution factor for shear at exterior beams

From Table 4.6.2.2.3c-1 for skewed bridges,

skew 0deg
CheckSkew if ( d 60deg)(3.5ft d S d 16ft)(20ft d L d 240ft) Ng t 4 "OK" "No Good" "OK"

cskew

1.0



0.20

Lts3 Kg



0.3

tan(

)

1.00

Correction factor for skew

A-214

8.

LIVE LOAD (cont'd)

Design Live Load Moment at Midspan:

wlane 0.64klf

Design lane load

Ptruck 32kip

Design truck axle load

IM 33%

Dynamic load allowance (truck only)

Mlane(x)

wlanex (L x) 2

(x) xL x2 L

Design lane load moment Influence coefficient for truck moment calculation

Mtruck(x)

Ptruck(x)max9x(L

x) 14ft(3x 4x(L x)



L)

9(

L x) 84 4(L x)

ft

Design truck moment

MHL93(x) Mlane(x) (1 IM)Mtruck(x)

HL93 design live load moment per lane

Mll.i(x) MHL93(x)gmint

Design live load moment at interior beam

Mll.e(x) MHL93(x)gmext
Mll(x) if BeamLoc = 1 Mll.e(x) Mll.i(x)

Design live load moment at exterior beam Design live load moment

Design Live Load Shear:

Vlane(x)

wlane



L 2



x

Vtruck(x)

Ptruck

9L



9x 4L

84ft



VHL93(x) Vlane(x) (1 IM)Vtruck(x)

Vll.i(x) VHL93(x)gvint

Vll.e(x) VHL93(x)gvext
Vll(x) if BeamLoc = 1 Vll.e(x) Vll.i(x)

Design lane load shear Design truck shear HL93 design live load shear Design live load shear at interior beam Design live load shear at exterior beam Design live load shear

A-215

9.

PRESTRESS PROPERTIES

Due to tension at the surface limit state be reduced to account for camber leveling forces, the prestress force required at the midspan is expected to be excessive at the ends when released. Not measuring the reduction of prestress moments. Estimate prestress losses at the midspan to find trial prestress forces, that will occur in the bottom tension fibers, that are less than allowable. Compute immediate losses in the prestressed steel and check released stresses at the end of the beam. Once you satisfy end stresses, estimate total loss of prestress. As long as these losses are not drastically different from the assumed stresses, the prestress layout should be acceptable. Concrete stress at all limit states are in Section 9.

yp.est 5in ycgp.est ybg yp.est 25.46in fp.est 25%

Assumed distance from bottom of beam to centroid of prestress at midspan Eccentricity of prestress from neutral axis, based on assumed location Estimate of total prestress losses at the service limit state

Compute bottom fiber service stresses at midspan using gross section properties.

X L 2
Mdl.ser Mg(X) Mfws(X) Mj(X) Mbar(X) 901kipft

Distance from support Total dead load moment

fb.serIII

Mdl.ser 0.8Mll(X) Sbg

fpj fpbt.max 202.5ksi

2.507ksi

Total bottom fiber service stress Prestress jacking force

fpe.est fpj 1 fp.est 151.9ksi

Estimate of effective prestress force

Aps.est

fb.serIII ft.all.ser





Ag

1

fpe.est Agycgp.est



Sbg

Nps.est

Aps.est

ceil



Ap

27

4.035in2

Estimated minimum area of prestressing steel Estimated number of strands required

Nps 38

Number of strands used ( Nps.max 40 )

The number above is used for the layout strand pattern and to compute the actual location of the strand group. After this is done the required area is computed again. If the estimated location is accurate the number of strands should be equal to the number of strands that we calculated above. The number of strands that was estimated was based on our assumed prestressed losses and gross section properties, which may not accurately reflect the final number of strands required for the design. These stresses for concrete are evaluated in Section 10. The geometry is assuming a vertical spacing of 2" between straight spans, as well as 2" for harped strands at the end of the beam. Harped strands are bundled at the midspan where the centroid is 5" from the bottom.

A-216

9.

PRESTRESS PROPERTIES (cont'd)

Nh 2 if Nps d 12 4 if 12 Nps d 24 6 if 24 Nps d 30
6 Nps 30 if Nps ! 30

Nh.add 16

Nh

min

Nh



Nh.add

16

2



floor

Nps 4

yh

1in (2in)1 0.5Nh 1



2

yhb 5in

Ns Nps Nh

Nh 14

Assumes all flange rows are filled prior to filling rows in web above the flange, which maximized efficiency. Use override below to shift strands from flange to web if needed to satisfy end stresses.

Nh 16

Additional harped strands in web (strands to be moved from flange to web)
16 strands or half of total strands maximum harped in web

yh 10in Ns 22

Centroid of harped strands from bottom, equally spaced Centroid of harped strands from bottom, bundled
Number of straight strands in flange

ys 1in 2in if Ns d 10

ys 4.273in Centroid of straight strands from bottom

(4in)Ns 20in Ns

if 10 Ns d 20

(6in)Ns 60in Ns

if 20 Ns d 24

3.5in otherwise

yp

Nsys Nhyhb Ns Nh

4.579in

Centroid of prestress from bottom at midspan

ycgp ybg yp 25.88in

Aps.req

fb.serIII ft.all.ser





Ag

fpe.est 1 Agycgp



Sbg

3.983in2

Eccentricity of prestress from neutral axis Estimated minimum area of prestressing steel

Nps.req

Aps.req

ceil

27

Ap

Estimated number of strands required

CheckNps if Nps d Nps.max Nps.req d Nps "OK" "No Good" "OK"

Aps.h NhAp 2.448in2 Aps.s NsAp 3.366in2 Aps Aps.h Aps.s 5.814in2

Area of prestress in web (harped) Area of prestress in flange (straight) Total area of prestress

A-217

9.

PRESTRESS PROPERTIES (cont'd)

Compute transformed section properties based on prestress layout.
Transformed Section Properties

Initial Transformed Section (release):

Final Transformed Section (service):

Ati 1167.4in2 Ixti 259764in4 ytti 14.172in ycgpi 25.249in ybti 29.828in

Stti 18329in3 Scgpi 10288in3 Sbti 8709in3

Atf 1163.7in2 Ixtf 257457in4 yttf 14.094in ycgpf 25.327in ybtf 29.906in

Sttf 18267in3 Scgpf 10165in3 Sbtf 8609in3

Determine initial prestress force after instantaneous loss due to elastic shortening. Use transformed properties to compute stress in the concrete at the level of prestress.

Pj fpjAps 1177.3kip

fcgpi

Pj



1 Ati



ycgpi
Scgpi



Mgr

Lg 2



Scgpi

3.108ksi

Jacking force in prestress, prior to losses
Stress in concrete at the level of prestress after instantaneous losses

fpES npifcgpi 18.266ksi

Prestress loss due to elastic shortening (5.9.5.2.3a-1)

fpi fpj fpES 184.234ksi

Initial prestress after instantaneous losses

Pi fpiAps 1071.1kip

Initial prestress force

Determine deflection of harped strands required to satisfy allowable stresses at the end of the beam at release.

fc.all.rel 0.6fci 3.84ksi
ft.all.rel max 0.0948 fciksi0.2ksi 0.200ksi

Lt 60dps 2.5ft

ycgp.t ycgp.b




ft.all.rel



Mgr Lt Stti



Pi





1 Ati





Stti




fc.all.rel



Mgr Lt Sbti



Pi





1 Ati





Sbti

20.262 in 24.899 in

Allowable compression before losses (5.9.4.1.1) Allowable tension before losses (Table 5.9.4.1.2-1) Transfer length (AASHTO 5.11.4.1) Prestress eccentricity required for tension
Prestress eccentricity required for compression

A-218

9.

PRESTRESS PROPERTIES (cont'd)

ycgp.req max ycgp.t ycgp.b 20.262in

Required prestress eccentricity at end of beam

yh.brg.req

ycgp.req ybti Ns Nh ysNs Nh

ytop.min 18in

16.843 in

hd 0.4

Minimum distance to harped prestress centroid from bottom of beam at centerline of bearing
Minimum distance between uppermost strand and top of beam
Hold-down point, fraction of the design span length

slopemax

if

dps

=

0.6in 1 12

1 8



0.125

yh.brg

h



ytop.min





0.5Nh 2



1 (2in)

20 in

yh.brg min yh.brgyhb slopemaxhdL 20in

Maximum slope of an individual strand to limit hold-down force to 4 kips/strand
Set centroid of harped strands as high as possible to minimize release and handling stresses
Verify that slope requirement is satisfied at uppermost strand

CheckEndPrestress if yh.brg t yh.brg.req"OK" "Verify release stresses." "OK"

yp.brg

Nsys Nhyh.brg Ns Nh

10.895 in

Centroid of prestress from bottom at bearing

slopecgp

yp.brg yp hdL

0.022

Slope of prestress centroid within the harping length

ypx(x)

yp slopecgp Lend hdL x if x d Lend hdL
yp otherwise

Distance to center of prestress from the bottom of the beam at any position

A-219

10. PRESTRESS LOSSES

Prestressed losses can be evaluated like regular concrete, in short-term and long-term losses. When the beam is a pretension girder there are instantaneous losses when the beam is shortened upon release of the prestress forces. Time-dependent losses happen when the beam is under creep and shrinkage of the beam concrete, creep and shrinkage o the deck concrete, and the relaxation of prestressed steel. These long term effects are separated into two stages that represent significant events in bridge construction. The first stage is the time between transfer of the prestress forces and placement of the decked beam and the second is the period of time between placement of the deck and the final service load. For decked beams the computation of long-term losses is slightly simplified due to the cross-section not changing between the two stages and the shrinkage term of the deck concrete is eliminated since the deck and beam being cast together. No losses or gains in the steel associated with deck placement after transfer.

AASHTO methods for estimating time-dependent losses: Approximate Estimate (5.9.5.3) Refined Estimate (5.9.5.4)

The Approximate method is based on systems with composite decks and is based on the following assumptions: timing of load application, the cross-section in which the load is applied, and the ratio of dead and live loads to the total load. The conditions for the beams to be fabricated, formed and loaded depend on conditions assumed in the development of the approximate method. The refined method is used to estimate time-dependent losses in the prestressed steel.

Equations 5.9.5.4 are time-dependent and calculate the age-adjustment factors that effect losses using gross section properties.

ti 1 tb 20 td 30 tf 20000

Time (days) between casting and release of prestress Time (days) to barrier casting (exterior girder only) Time (days) to erection of precast section, closure joint pour Time (days) to end of service life

Terms and equations used in the loss calculations:

KL 45

VS Ag 3.883in Peri

ks

max1.45



0.13

VS in

1.0

1.00

khc 1.56 0.008H 1.00

Prestressing steel factor for low-relaxation strands (C5.9.5.4.2c) Volume-to-surface ratio of the precast section
Factor for volume-to-surface ratio (5.4.2.3.2-2)
Humidity factor for creep (5.4.2.3.2-3)

khs 2.00 0.014H 1.02

kf

5 1 fci

ksi

0.676

Humidity factor for shrinkage (5.4.2.3.3-2) Factor for effect of concrete strength (5.4.2.3.2-4)

A-220

10. PRESTRESS LOSSES (cont'd)

ktd(t)

t 61 4 fci t
ksi

t tinit 1.9kskhckfktd(t) tinit 0.118

sh(t) kskhskfktd(t) 0.4810 3

Time development factor (5.4.2.3.2-5)
Creep coefficient (5.4.2.3.2-1) Concrete shrinkage strain (5.4.2.3.3-1)

Time from Transfer to Erection:

epg yp ybg 25.877in

Eccentricity of prestress force with respect to the neutral axis of the gross non-composite beam, positive below the beam neutral axis

fcgp

Pi



1 Ag



epg2 Ixg



Mg

L 2

Ixg



yp



ybg

3.148ksi

Stress in the concrete at the center prestress immediately after transfer

fpt max fpi0.55fpy 184.234ksi

Stress in strands immediately after transfer (5.9.5.4.2c-1)

bid tdti 0.589 bif tf ti 1.282 bid sh td ti 1.490 u 10 4

Creep coefficient at erection due to loading at transfer Creep coefficient at final due to loading at transfer Concrete shrinkage between transfer and erection

Kid

1

1



npi

Aps Ag





1



Agepg2 Ixg





1



0.7bif

0.809

Age-adjusted transformed section coefficient (5.9.5.4.2a-2)

fpSR bidEpKid 3.433ksi

Loss due to beam shrinkage (5.9.5.4.2a-1)

fpCR npifcgpbidKid 8.807ksi

fpR1



fpt



log

KL log

24td 24ti





fpt

fpy



0.551




3

fpSR fpt

fpCR

Kid

1.142ksi

Loss due to creep (5.9.5.4.2b-1)
Loss due to relaxation (C5.9.5.4.2c-1

fpid fpSR fpCR fpR1 13.382ksi

A-221

10. PRESTRESS LOSSES (cont'd)

Time from Erection to Final: epc epg 25.877in

Ac Ag

Ic Ixg

fcd

Mfws

L 2





Mj

L 2





fpid

Scgpf

np

2.413ksi

bdf tf td 0.858

bif sh tf ti 3.302 u 10 4

bdf bif bid 1.813 u 10 4

Eccentricity of prestress force does not change Section properties remain unchanged
Change in concrete stress at center of prestress due to initial time-dependent losses and superimposed dead load. Deck weight is not included for this design. Creep coefficient at final due to loading at erection
Concrete shrinkage between transfer and final
Concrete shrinkage between erection and final

Kdf

1

1



n

pi

Aps Ac



1



Acepc2 Ic





1

0.7bif

0.809

Age-adjusted transformed section coefficient remains unchanged

fpSD bdfEpKdf 4.177ksi

Loss due to beam shrinkage

fpCD npifcgp bif bid Kdf npfcdbdfKdf 19.157ksi

Loss due to creep

fpR2 fpR1 1.142ksi

Loss due to relaxation

fpSS 0

Loss due to deck shrinkage

fpdf fpSD fpCD fpR2 fpSS 24.476ksi

Prestress Loss Summary fpES 18.266ksi fpLT fpid fpdf 37.858ksi fpTotal fpES fpLT 56.124ksi

fpES 9% fpj

fpLT fpj

18.7 %

fpTotal fpj

27.7 %

fpe fpj fpTotal 146.4ksi

CheckFinalPrestress if fpe d fpe.max"OK" "No Good" "OK"

fp.est 25% Final effective prestress

A-222

11. CONCRETE STRESSES

Concrete Stresses at release, during handling and at final service are computed and compared to approximated values for each stage.

Concrete Stresses at Release

When calculating the stresses at release use the overall beam length due to the beam being supported at each end in the casting bed after prestress forces are transformed.

Define locations for which stresses are to be calculated:

xr

Lg 0


min

Lt

Lend



Lg Lg

max

Lt

Lend



Lg Lg

T 0.1 0.2 0.3 hd 0.5


ir 1 lastxr

Functions for computing beam stresses:

ftop.r(x)

min

x Lt

1



Pi



1 Ati



ybti

ypx(x)



Stti





Mgr(x) Stti

fbot.r(x)

min

x Lt

1



Pi



1 Ati



ybti

ypx(x)
Sbti



Mgr(x) Sbti

Top fiber stress at release Bottom fiber stress at release

4

ftop.r( x) ksi 3

fbot.r( x)
ksi 2
fc.all.rel
ksi 1
ft.all.rel
ksi

0

0

Stresses in Concrete at Release (Half Beam)

Stress (ksi)

1

0

4

8

12

16

20

24

28

32

36

40

x

ft

Distance along Beam (ft)

A-223

11. CONCRETE STRESSES (cont'd) Compare beam stresses to allowable stresses.
ft.all.rel 0.2ksi

Allowable tension at release

fc.all.rel 3.84ksi

Allowable compression at release

TopRelir ftop.r xrir

TopRelT ( 0.000 0.097 0.130 0.097 0.071 0.081 0.126 0.115 )ksi

CheckTopRel if max(TopRel) d fc.all.rel min(TopRel) t ft.all.rel "OK" "No Good" "OK"

BotRelir fbot.r xrir

BotRelT ( 0.000 2.484 3.122 3.053 2.999 3.019 3.115 3.090 )ksi

CheckBotRel if max(BotRel) d fc.all.rel min(BotRel) t ft.all.rel "OK" "No Good" "OK"

Concrete Stresses During Lifting and Transportation

Lifting and transportation stresses can govern over final stresses due to different support locations, dynamic effects that dead load can cause during movement, bending stresses during lifting and superelevation of the roadway in shipping. End diaphragms on both ends are assumed. For prestressing effects, calculate the effective prestressed force losses between transfer and building.

a h 3.75ft

Maximum distance to lift point from bearing line

a' a Lend 5.75ft

Distance to lift point from end of beam

Pdia max WiaWsa 13.8kip

Pm

Pj1


fpES fpid



fpj



993.3kip

Approximate abutment weight Effective prestress during lifting and shipping

Define locations for which stresses are to be calculated:

xe

Lg 0


min

Lt

Lend



Lg Lg

max

Lt

Lend



Lg Lg

a' Lg

T hd 0.5


ie 1 lastxe

Compute moment in the girder during lifting with supports at the lift points.

Mlift(x)




wg



wbar 2

x2





Pdia

x

if

x d a'


Mgr(x) Mgr(a')

wg



wbar 2

(a')2





Pdia

a'

otherwise

A-224

11. CONCRETE STRESSES (cont'd) Functions for computing beam stresses:

ftop.lift(x)

min

x Lt

1



Pm



1 Atf



ybtf

ypx(x)



Sttf





Mlift(x) Sttf

ftop.DIM.inc(x)

min

x Lt

1



Pm



1 Atf



ybtf

ypx(x)



Sttf





Mlift(x) (1 Sttf



DIM)

ftop.DIM.dec(x)

min

x Lt

1



Pm



1 Atf



ybtf

ypx(x)



Sttf





Mlift(x) (1 Sttf



DIM)

Top fiber stress during lifting
Top fiber stress during lifting, impact increasing dead load
Top fiber stress during lifting, impact decreasing dead load

TopLift1ie TopLift2ie TopLift3ie

ftop.lift xeie ftop.DIM.inc xeie ftop.DIM.dec xeie

TopLift1T ( 0.000 0.165 0.214 0.305 0.308 0.296 )ksi TopLift2T ( 0.000 0.171 0.222 0.327 0.245 0.227 )ksi TopLift3T ( 0.000 0.159 0.206 0.284 0.371 0.364 )ksi

fbot.lift(x)

min

x Lt

1



Pm



1 Atf



ybtf

ypx(x)



Sbtf





Mlift(x) Sbtf

fbot.DIM.inc(x)

min

x Lt

1



Pm



1 Atf



ybtf

ypx(x)



Sbtf





Mlift(x) (1 Sbtf



DIM)

fbot.DIM.dec(x)

min

x Lt

1



Pm



1 Atf



ybtf

ypx(x)



Sbtf





Mlift(x) (1 Sbtf



DIM)

Bottom fiber stress during lifting
Bottom fiber stress during lifting, impact increasing dead load
Bottom fiber stress during lifting, impact decreasing dead load

BotLift1ie BotLift2ie BotLift3ie

fbot.lift xeie fbot.DIM.inc xeie fbot.DIM.dec xeie

BotLift1T ( 0.000 2.481 3.118 3.312 3.318 3.292 )ksi BotLift2T ( 0.000 2.494 3.135 3.358 3.184 3.147 )ksi BotLift3T ( 0.000 2.468 3.101 3.267 3.452 3.437 )ksi

Allowable stresses during handling:
fcm fc.erec fc 7.2ksi
fc.all.erec 0.6fcm 4.32ksi
ft.all.erec ft.erec fcm 0.429ksi

Assumed concrete strength when handling operations begin Allowable compression during lifting and shipping Allowable tension during lifting and shipping

A-225

11. CONCRETE STRESSES (cont'd) Stresses in Concrete During Lifting (Half Beam)

Stress (ksi)

ftop.lift( x) ksi

ftop.DIM.inc(x) 4 ksi

ftop.DIM.dec( x) ksi

fbot.lift( x) ksi

fbot.DIM.inc ( x)

ksi

2

fbot.DIM.dec( x) ksi

fc.all.erec ksi

ft.all.erec
ksi 0
0

0

4

8

12

16

20

24

28

32

36

40

x

ft

Distance along Beam (ft)

Compare beam stresses to allowable stresses.

TopLiftMaxie max TopLift1ie TopLift2ie TopLift3ie

TopLiftMaxT ( 0 0.159 0.206 0.284 0.245 0.227 )ks

TopLiftMinie min TopLift1ie TopLift2ie TopLift3ie

TopLiftMinT ( 0 0.171 0.222 0.327 0.371 0.364 )ks

CheckTopLift if max(TopLiftMax) d fc.all.erec min(TopLiftMin) t ft.all.erec "OK" "No Good" "OK"

BotLiftMaxie max BotLift1ie BotLift2ie BotLift3ie

BotLiftMaxT ( 0 2.494 3.135 3.358 3.452 3.437 )ksi

BotLiftMinie min BotLift1ie BotLift2ie BotLift3ie

BotLiftMinT ( 0 2.468 3.101 3.267 3.184 3.147 )ksi

CheckBotLift if max(BotLiftMax) d fc.all.erec min(BotLiftMin) t ft.all.erec "OK" "No Good" "OK"

A-226

11. CONCRETE STRESSES (cont'd)

Concrete Stresses at Final

Stresses are calculated using design span length. The top flange compression and bottom flange under tension are computed at Service I and Service III states.

fc.all.ser1 0.4fc 3.2ksi fc.all.ser2 0.6fc 4.8ksi

Allowable compression due to effective prestress and dead load (Table 5.9.4.2.1-1)
Allowable compression due to effective prestress, permanent load, and transient loads, as well as stresses during shipping and handling (Table 5.9.4.2.1-1)

ft.all.ser 0ksi

Allowable tension (computed previously)

Pe fpeAps 851.0kip

Effective prestress after all losses

Compute stresses at midspan and compare to allowable values.

ftop.ser1(x)

Lend min
Lt

x

1




Pe



1 Atf



ybtf

ypx(x)



Sttf





Mg

x Lend Stti

Mbar(x) Mfws(x) Mj(x) Sttf

ftop.ser2(x)

Lend min
Lt

x

1




Pe



1 Atf



ybtf

ypx(x)



Sttf





Mg

x Lend Stti

Mbar(x) Mfws(x) Mj(x) Mll(x) Sttf

fbot.ser(x)

Lend min
Lt

x

1




Pe



1 Atf



ybtf

ypx(x)



Sbtf





Mg

x Lend Sbti

Mbar(x) Mfws(x) Mj(x) 0.8Mll(x) Sbtf

Stresses in Concrete at Service (Half Beam) 6

ftop.ser1( x) ksi
ftop.ser2( x) ksi 4

Stress (ksi)

fbot.ser( x) ksi
ft.all.ser ksi 2
fc.all.ser1 ksi
fc.all.ser2 ksi 0

0

4

8

12

16

20

24

28

32

36

40

x

ft

Distance along Beam (ft)

A-227

11. CONCRETE STRESSES (cont'd)

Compare beam stresses to allowable stresses.

xs

L Lt L

0.1

0.15

0.2

0.25

0.3

0.35

hd

0.45

0.5 T

is 1 lastxs

TopSer1is ftop.ser1 xsis TopSer2is ftop.ser2 xsis

TopSer1T TopSer2T

( 0.020 0.049 0.096 0.130 0.153 0.165 0.164 0.151 0.139 0.140 )ksi ( 0.089 0.292 0.437 0.554 0.643 0.705 0.743 0.759 0.761 0.759 )ksi

CheckCompSerI if max(TopSer1) d fc.all.ser1 max(TopSer2) d fc.all.ser2 "OK" "No Good" "OK"

BotSeris fbot.ser xsis

BotSerT ( 2.143 1.769 1.505 1.292 1.131 1.022 0.959 0.936 0.939 0.941 )ksi

CheckTenSerIII if min(BotSer) t ft.all.ser"OK" "No Good" "OK"

12. FLEXURAL STRENGTH

Confirm flexural resistance at Strength Limit State. Calculate Factored moment at midspan during Strength I load combination. Compare this to factored resistance in AASHTO LRFD 5.7.3.

MDC(x) Mg(x) Mbar(x) Mj(x)

Self weight of components

MDW(x) Mfws(x)

Weight of future wearing surface

MLL(x) Mll(x)

Live load

MStrI(x) 1.25MDC(x) 1.5MDW(x) 1.75MLL(x)

Factored design moment

For minimum reinforcement check, per 5.7.3.3.2

fcpe

Pe



1 Ag



ycgp
Sbg

3.527ksi

Mcr fr.cm fcpe Sbg 3019kipft

Mu(x) max MStrI(x) min 1.33MStrI(x) 1.2Mcr

Concrete compression at extreme fiber due to effective prestress Cracking moment (5.7.3.3.2-1)
Design moment

A-228

12. FLEXURAL STRENGTH (cont'd)

Compute factored flexural resistance.

1

max0.650.85 0.05 fc 4



ksi

k

21.04



fpy

0.28



fpu

dp(x) h ypx x Lend

0.65 dp(X)

40.421 in

hf d7 8in

btaper

b6 b5 2

16 in

htaper d5 2in

a(x) c(x)

Apsfpu

0.85fcbf



k 1



Aps



fpu dp(x)



a(x)

1

a(X) 2.517in c(X) 3.873in

CheckTC

if dcp((XX))

d



.003 .003 .005



"OK"

"NG"

"OK"

Stress block factor (5.7.2.2)
Tendon type factor (5.7.3.1.1-2) Distance from compression fiber to prestress centroid Structural flange thickness Average width of taper at bottom of flange Depth of taper at bottom of flange Depth of equivalent stress block for rectangular section
Neutral axis location
Tension-controlled section check (midspan)

f

min1.0max0.750.583 0.25 dp(X) 1





c(X)

1.00

Resistance factor for prestressed concrete (5.5.4.2)

fps

fpu1



k

c(X) dp(X)



262.8ksi

Average stress in the prestressing steel (5.7.3.1.1-1)

Ld

1.6 ksi





fps



2 3



fpe



dps

11.012 ft

Bonded strand devlepment length (5.11.4.2-1)

fpx(x)

fpe x Lend
Lt

if x d Lt Lend

Stress in prestressing steel along the length for bonded strand (5.11.4.2)

fpe

x

Lend Ld Lt

Lt

fps



fpe

if Lt Lend x d Ld Lend

fps otherwise

Mr(x)

fApsfpx(x)dp(x)



a(x) 2



Flexure resistance along the length

A-229

12. FLEXURAL STRENGTH (cont'd)

xmom

L 0.01

Lt Lend L

Ld Lend L

hd

0.5 T

Mrximom Mr xmomimom

Muximom Mu xmomimom

imom 1 last xmom

DCmom

Mux Mrx

max DCmom 0.727

CheckMom if max DCmom d 1.0"OK" "No Good"

"OK"

Demand-Capacity ratio for moment Flexure resistance check

Design Moment and Flexure Resistance (Half Beam)

Moment (kipft)

MStrI( x) kip ft
1.2 Mcr kip ft

4000

1.33 MStrI( x) kip ft

Mu( x) kip ft

2000

Mr( x) kip ft

0

0

4

8

12

16

20

24

28

32

36

40

x

ft

Distance along Beam (ft)

A-230

13. SHEAR STRENGTH

Shear Resistance

Use Strength I load combination to calculate factored shear at the critical shear section and at tenth points along the span. Compare it to factored resistance in AASHTO LRFD 5.8.

VDC(x) Vg(x) Vbar(x) Vj(x)

Self weight of components

VDW(x) Vfws(x)

Weight of future wearing surface

VLL(x) Vll(x)

Live load

Vu(x) 1.25VDC(x) 1.5VDW(x) 1.75VLL(x)

Factored design shear

v 0.90

Resistance factor for shear in normal weight concrete (AASHTO LRFD 5.5.4.2)

dend h ypx Lend 34.105in

Depth to steel centroid at bearing

dv min 0.9dend0.72h 30.695in

Effective shear depth lower limit at end

Vp(x)

Peslopecgp

x

Lend Lt

if x d Lt Lend

Peslopecgp if Lt Lend x d hdL

0 otherwise

bv b3 6in

vu(x)

Vu(x) vVp(x) vbvdv

Mushr(x) max MStrI(x) Vu(x) Vp(x) dv

fpo 0.7fpu 189ksi

Vertical component of effective prestress force
Web thickness Shear stress on concrete (5.8.2.9-1) Factored moment for shear Stress in prestressing steel due to locked-in strain after casting concrete

s(x)



Mu(x)

max0.410 3 dv



Vu(x) Vp(x) EpAps



Aps

fpo



Steel strain at the centroid of the prestressing

steel

(x)

4.8

1 750s(x)

(x) 29 3500s(x) deg

Shear resistance parameter Principal compressive stress angle

Vc(x)

0.0316ksi(x)

fc ksi



bv

dv

Concrete contribution to total shear resistance

A-231

13. SHEAR STRENGTH (cont'd)

90deg

Angle of inclination of transverse reinforcement

Av ( 1.02 0.62 0.62 0.62 0.31 )Tin2

sv ( 3 6 6 12 12 )Tin

Transverse reinforcement area and spacing provided

xv ( 0 0.25h 1.5h 0.3L 0.5L 0.6L )T

xvT ( 0 0.938 5.625 18 30 36 )ft

Avs(x) for i 1 last Av

out m Avi svi

if xvi d x d xvi1

.

out

Vs(x) Avs(x)fydv(cot((x)) cot())sin()

Steel contribution to total shear resistance

Vr(x) v Vc(x) Vs(x) Vp(x)

Factored shear resistance

xshr

for i 1 100

outi

m

i

0.5L 100

out

ishr 1 last xshr

Vuxishr Vu xshrishr

Vrxishr Vr xshrishr

DCshr

Vux Vrx

max DCshr 0.574

CheckShear if max DCshr d 1.0"OK" "No Good" "OK" Shear resistance check

Shear (kips)

Design Shear and Resistance (Half Beam)

400 Vu( x)
kip 300

Vr(x) 200 kip 100

0

0

4

8

12

16

20

24

28

32

36

40

x

ft

Distance along Beam (ft)

A-232

13. SHEAR STRENGTH (cont'd)

Longitudinal Reinforcement

Al.req(x)

a1 m

MStrI(x)

ffpx(x)dp(x)



a(x) 2



a2

m

Vu(x)



v



0.5Vs(x)



Vp( x) cot( ( x) )


fpx(x)

a3 m

Mushr(x) dvf




Vu(x) v



Vp(x)

0.5Vs(x)cot((x))


fpx(x)

min(a1a2) if x d dv 5in

min(a1a3) otherwise

Longitudinal reinforcement required for shear (5.8.3.5)

As.add 0.40in2

Ld.add 18.67ft

Additional longitudinal steel and developed length from end of beam

Al.prov(x)

if x Ld.add LendAs.add0

ApNs

x

Lend Ld

if x d Ld Lend

ApNs

if

Ld



Lend



x

d

yh.brg 0.5h slopecgp



0.5Nh 2



1 (2in)cot

slopecgp

Ap Nh Ns otherwise

Steel Area (in2)

6 Al.req( x)
in2 4
Al.prov( x) 2
in2
0 0

Longitudinal Reinforcement Required and Provided (Half Beam)

4

8

12

16

20

24

28

32

36

40

x

ft

Distance along Beam (ft)

Al.reqishr Al.req xshrishr

Al.provishr Al.prov xshrishr

DClong

Al.req Al.prov

max DClong 0.844

CheckLong if max DClong d 1.0"OK" "No Good" "OK"

Longitudinal reinforcement check

A-233

14. SPLITTING RESISTANCE Splitting Resistance Checking splitting by zone of transverse reinforcement. Defined in Shear Strength section.

As

Av1xv2 sv1

3.825in2

fs 20ksi

Pr fsAs 76.5kip

Pr.min 0.04Pj 47.1kip

CheckSplit if Pr t Pr.min"OK" "No Good" "OK"

Limiting stress in steel for crack control (5.10.10.1) Splitting resistance provided (5.10.10.1-1) Minimum splitting resistance required Splitting resistance check

15. CAMBER AND DEFLECTIONS Calculate Deflections due to different weights, joints, and future wearings.

ps

Pi





ycgp

Lg2



ybg



yp.brg



hdL



Lend

2

EciIxg 8

6



1.456in Deflection due to prestress at release

gr

5 wgLg4 384 EciIxg

0.427in

Deflection due to self-weight at release

bar

5 wbarLg4 384 EcIxg

0.124in

Deflection due to barrier weight

j

5 wjL4 if (BeamLoc = 0 1 0.5) 384 EcIxg

0.006in

2

Deflection due to longitudinal joint

fws

5



wfwsL4 if BeamLoc

=

S 0 1



Wb

384 EcIxg

S

0.036in

Deflection due to future wearing surface

tbar 20

Age at which barrier is assumed to be cast

T ti 7 14 21 28 60 120 240 T

Concrete ages at which camber is computed

A-234

15. CAMBER AND DEFLECTIONS (cont'd)
cr1(t) t titi gr ps

cr2(t) t titi tbar titi gr ps t tbartbar bar

cr3(t) t titi td titi gr ps t tbartbar td tbartbar bar t tdtd j

cr(t) Defl(t)

cr1(t) if t d tbar
cr1 tbar cr2(t) if tbar t d td cr1 tbar cr2 td cr3(t) if t ! td
gr ps cr1(t) if t d tbar gr ps cr1 tbar bar cr2(t) if tbar t d td gr ps cr1 tbar bar cr2 td j cr3(t) if t ! td

C for j 1 last(T)
outj m Defl Tj
out

CT ( 1.03 1.221 1.385 1.38 1.457 1.664 1.832 1.95 2.105 )in

Deflection (in)

3
cr( t) in 2
Defl( t) 1
in

60-Day Deflection at Midspan

0

0

20

40

60

t

Age of Concrete (days)

Deflection (in)

3
cr( t) in 2
Defl( t) 1
in
0 0

Long-term Deflection at Midspan

500

1000

t

Age of Concrete (days)

1500

2000

A-235

16. NEGATIVE MOMENT FLEXURAL STRENGTH
Calculate factored moment that must be resisted across the interior pier and find required steel to be developed in the top flange.

Negative Live Load Moment
Compute the negative moment over the interior support due to the design live load load, in accordance with AASHTO LRFD 3.6.1.3.1.

Live Load Truck and Truck Train Moment Calculations

min Mtruck 738kipft

min Mtrain 1186kipft

Mneg.lane

wlaneL2 2

1152kipft

Maximum negative moment due to a single truck
Maximum negative moment due to two trucks in a single lane
Negative moment due to lane load on adjacent spans

Mneg.truck Mneg.lane (1 IM)min Mtruck 2134kipft

Live load negative moment for single truck

Mneg.train 0.9Mneg.lane (1 IM)min Mtrain 2456kipft

Live load negative moment for two trucks in a single lane

MHL93.neg min Mneg.truck Mneg.train 2456kipft

Design negative live load moment, per design lane

Mll.neg.i MHL93.neggmint 1644kipft Mll.neg.e MHL93.neggmext 1712kipft
MLL.neg if BeamLoc = 1 Mll.neg.eMll.neg.i 1712kipft

Design negative live load moment at interior beam
Design negative live load moment at exterior beam
Design negative live load moment

Factored Negative Design Moment

Dead load applied to the continuity section at interior supports is limited to the future overlay.

MDW.neg

wfwsL2 2

357kipft

Mu.neg.StrI 1.5MDW.neg 1.75MLL.neg 3532kipft

Superimposed dead load resisted by continuity section
Strength Limit State

Mu.neg.StrI 1.0MDW.neg 1.0MLL.neg 2069kipft

Service Limit State

A-236

16. NEGATIVE MOMENT FLEXURAL STRENGTH (cont'd)

Reinforcing Steel Requirement in the Top Flange for Strength

f 0.90

bc b1 26in
dnms h tsac 0.5 tflange tsac

40 in

Reduction factor for strength in tensioncontrolled reinforced concrete (5.5.4.2)
Width of compression block at bottom flange
Distance to centroid of negative moment steel, taken at mid-depth of top flange

Ru

Mu.neg.StrI

f



bcd

2
nms

0.663ksi

m

fy

8.824

0.85fc

req

1

1



m

1



2

m

Ru



fy

0.0117

Anms.req reqbcdnms 12.12in2

As.long.t 2.0in2

As.long.b 2.0in2

Abar 0.44in2

Anms.t

2 3

Anms.req



As.long.t

nbar.t

Anms.t

ceil



Abar

14

6.08 in2

Anms.b

1 3

Anms.req



As.long.b

nbar.b

Anms.b

ceil



Abar

5

2.04 in2

sbar.top

S Wj 6in nbar.t 1

6.404in

As.nms nbar.t nbar.b Abar As.long.t As.long.b

12.36in2

a As.nmsfy 4.195in 0.85fcbc

Mr.neg

fAs.nmsfydnms



a 2



2108kipft

DCneg.mom

Mu.neg.StrI Mr.neg

0.982

CheckNegMom if DCneg.mom d 1.0"OK" "No Good"

"OK"

Factored load, in terms of stress in concrete at depth of steel, for computing steel requirement Steel-to-concrete strength ratio
Required negative moment steel ratio
Required negative moment steel in top flange Full-length longitudinal reinforcement to be made continuous across joint Additional negative moment reinforcing bar area Additional reinforcement area required in the top mat (2/3 of total) Additional bars required in the top mat
Additional reinforcement area required in the bottom mat Additional bars required in the top mat
Spacing of bars in top mat
Total reinforcing steel provided over pier
Depth of compression block
Factored flexural resistance at interior pier
Negative flexure resistance check

A-237

File Name: Prestressed Concrete Girder-40ft.xmcd

DECKED PRECAST PRESTRESSED CONCRETE GIRDER DESIGN FOR ABC

Unit Definition:

kcf { kipft 3

This example is for the design of a superstructure system that can be used for rapid bridge replacement in an Accelerated Bridge Construction (ABC) application. The following calculations are intended to provide the designer guidance in developing a similar design with regard to design considerationS characteristic of this type of construction, and they shall not be considered fully exhaustive.
Overall Width, W

Barrier Width, Wb

Joint Width, Wj

Roadway Width, Wr Slope, CS

S Wj 2


Beam Spacing, S TYPICAL SECTION THROUGH SPAN

Lend Bridge Geometry:

Design Span Length, L Girder Length, Lg

GIRDER ELEVATION

L 40ft

W 63ft

Smax 8ft

Ng

W Wj

ceil



Smax

8

S W Wj 7.938ft Ng

Lend 2ft Wb 1.5ft Wj 0.5ft

skew 0deg

Minimum number of girders in cross-section

Girder spacing

A-238

ORDER OF CALCULATIONS

1. Introduction 2. Design Philosophy 3. Design Criteria 4. Beam Section 5. Material Properties 6. Permanent Loads 7. Precast Lifting Weight 8. Live Load 9. Prestress Properties 10. Prestress Losses 11. Concrete Stresses 12. Flexural Strength 13. Shear Strength 14. Splitting Resistance 15. Camber and Deflections 16. Negative Moment Flexural Strength

1.

INTRODUCTION

The bridge that is designed in this example consists of precast prestressed concrete girders with a top flange equal to the beam spacing, so the top flange will be the riding surface of the designed bridge. The purpose for these girders is to rapidly construct the bridge by providing a precast deck on the girders, which eliminates cast-in-place decks in the field and improves safety.

The concepts used in this example have been taken from on-going research, which focuses on the benefits of decked precast beams and promoting widespread acceptance from transportation and construction industries. The cross-section is adapted from the optimized girder sections recommended by NCHRP Project No. 12-69, Design and Construction Guidelines for Long-Span Decked Precast, Prestressed Concrete Girder Bridges. The girder design has not taken into account the option to re-deck due to the final re-decked girder, without additional prestressed, having a shorter life span. Use of stainless steal rebar and the application of a future membrane can get ride of the need to replace the deck. This case is included in "re-deckability".

The bridge used in this example is a general design of a typical bridge in Georgia. The calculations can be modified for single-span and multiple-span bridges due to the beam design moments are not reduced for continuity at intermediate supports (continuity details are not shown in this example). The cross-section consists of a four-lane roadway with normal crown, with standard shoulder lengths and barrier walls. The precast prestressed concrete girder has been uniformly designed to simplify bearing details. The girder flanges are 9'' at the tips, imitating a 8'' slab with a '' allowable wear and another '' for smoothness and profile adjustments.

This example is intended to illustrate design aspect specific to precast prestressed concrete girders used for ABC application. Girders with uncommon cross-sections, high self-weight, or unconventional load application create major concerns and more detailed calculations must be done.

A-239

2.

DESIGN PHILOSOPHY

The geometry of the section is based on GDOT standards and general bridges across the state of Georgia. Depth variations are dependent on the construction company but must maintain the shapes of the top flange and the bottom bulb.

Concrete strengths can vary but are mostly between 6 ksi and 10 ksi. For the purpose of these calculations the concrete with a 28-day minimum compressive strength of 8 ksi is used. Due to its casting sequence this beam is unable to take advantage of composite sequences along with tension at the bottom of the beam at the service limit state being limited. This is further discussed in section 4 along with end region stresses being critical. Therefore the minimum concrete strength at release must be 80 percent of the 28-day compressive strength, which increases the allowable stresses at the top and bottom of the section. The prestressed steel can also be optimized to minimize stresses at the end region.

The prestressed steel is arranged in a draped, or harped, pattern to maximize the midspan effectiveness while it minimizes the failure at the end of the beam where is concrete is easily overstressed due to the lack of dead load acting on the beam. The strand group is optimized at the midspan by bundling the strands between hold-points, maximizing the stiffness of the strand group. The number and deflection angles are depended on the type of single strands you are using for the girder. In longer span cases the concrete at the end of the girder will be too large and will debond. Without harped strands it is unlikely to reduce stresses to the allowable limit, since harped strands are required this method of stress relief will be used without debonding for long spans.

3.

DESIGN CRITERIA

Criteria has been selected to govern the design of these concrete girders while following provisions set by AASHTO, GDOT design specifications, as well as criteria of past projects and current research related to ABC and decked precast sections. A summary of the limiting design values are categorized as section constraints, prestress limits, and concrete limits.

Section Constraints:

Wpc.max 200kip
Smax 8ft Prestress Limits:

Upper limit on the weight of the entire precast element, based on common lifting and transport capabilities without significantly increasing time and/or cost due to unconventional equipment or permits
Upper limit on girder spacing and, therefore, girder flange width (defined on first page)

Fhd.single 4kip

Maximum hold-down force for a single strand

Fhd.group 48kip

Maximum hold-down force for the group of harped strands

Stress limits in the prestressing steel immediately prior to prestress and at the service limit state after all losses are as prescribed by AASHTO LRFD.

A-240

3.

DESIGN CRITERIA (cont'd)

Concrete Limits:

Allowable concrete stresses meet standards set by AASHTO LRFD with one exception that at Service III Limit State, allowable bottom fiber tension when camber leveling forces are to be neglected, regardless of exposure, are to be 0-ksi. Minimum strength of concrete at release is 80 percent of the 28-day minimum compressive strength (f-ksi).

ft.all.ser 0ksi

Allowable bottom fiber tension at the Service III Limit State, when camber leveling forces are to be neglected, regardless of exposure

As previously mentioned, release concrete strength is specified as 80 percent of the minimum 28-day compressive strength to maximize allowable stresses in the end region of beam at release.

fc.rel(f ) 0.80f

Minimum strength of concrete at release

Due to various lifting and transportation conditions, stresses in the concrete need to be considered. A "no cracking" approach is used for allowable tension due to reduced lateral stability after cracking. Assuming the girders will be lifted before the 28-day minimum strength is attained, the strength of concrete during lifting and transportation is assumed to be 90 percent of the 28-day minimum compressive strength. A dynamic dead load allowance of 30 percent is used for compression during handling. A factor of safety (FS) of 1.5 is used against cracking during handling.

DIM 30%

Dynamic dead load allowance

fc.erec(f ) 0.90f

FSc 1.5

ft.erec(f )

0.24 f ksi FSc

Assumed attained concrete strength during lifting and transportation Factor of safety against cracking during lifting transportation Allowable tension in concrete during lifting and transportation to avoid cracking

A-241

4.

BEAM SECTION

Use trapezoidal areas to define the cross-section. The flange width is defined as the beam spacing less the width of the longitudinal closure joint to reflect pre-erection conditions. Live load can be conservatively applied to this section, as well.

h 40.5in

Beam section depth

tflange 9in tsac 1in

Flange thickness at tip

Total sacrificial depth for grinding and wear

y

b1 26in b2 26in b3 6in b4 6in b5 10in b6 42in b7 89.25in

b2 26in b3 6in b4 6in b5 10in b6 42in b7 S Wj b8 S Wj

d3 h tsac d

Gross Section Properties

d1 6in d2 4.5in
d4 2in d5 2in d6 0in d7 tflange tsac
d3 17in

b n+1

bn

b n-1 bn-2

d n-2

b3 b2
b1

d2
d1 x

TYPICALGIRDERSECTIONCOMPR ISED OFnTRAPEZOIDALR EGIONS

dn dn-1

bf 89.25in Ag 1112in2 Ixg 182071in4
ytg 12.191in Stg 14934.5in3 Iyg 487596in4

ybg 27.309in Sbg 6667.1in3

Precast girder flange width Cross-sectional area (does not include sacrifical thickness) Moment of inertia (does not include sacrificial thickness) Top and bottom fiber distances from neutal axis (positive up) Top and bottom section moduli Weak-axis moment of inertia

GIRDER SECTION PLOT (N.T.S.) 42.5

36.938

31.375

25.813

20.25

14.688

9.125

3.563

2

50 40 30 20 10 0

10 20 30 40

50

A-242

5.

MATERIAL PROPERTIES

These properties are standard (US units) values with equations that can be found in AASHTO LRFD Bridge Design Specifications.

Concrete: fc 8ksi
fci fc.rel fc

6.4 ksi

c .150kcf

K1 1.0

Eci

33000

K1



c kcf

1.5

fciksi

4850 ksi

Ec

33000K1



c kcf



1.5

fcksi

5422 ksi

Minimum 28-day compressive strength of concrete Minimum strength of concrete at release Unit weight of concrete Correction factor for standard aggregate (5.4.2.4) Modulus of elasticity at release (5.4.2.4-1)
Modulus of elasticity (5.4.2.4-1)

fr.cm 0.37 fcksi 1.047ksi fr.cd 0.24 fcksi 0.679ksi H 70

Modulus of rupture for cracking moment (5.4.2.6) Modulus of rupture for camber and deflection (5.4.2.6) Relative humidity (5.4.2.3)

Prestressing Steel:

fpu 270ksi

fpy 0.9fpu 243ksi

fpbt.max 0.75fpu 202.5ksi

fpe.max 0.80fpy 194.4ksi

Ep 28500ksi

dps 0.5in Ap 0.153in2

Nps.max 40

npi

Ep Eci

5.9

np

Ep Ec

5.3

Mild Steel:

Ultimate tensile strength Yield strength, low-relaxation strand (Table 5.4.4.1-1) Maximum stress in steel immediately prior to transfer Maximum stress in steel after all losses Modulus of elasticity (5.4.4.2) Strand diameter Strand area Maximum number of strands in section Modular ratio at release
Modular ratio

A-243

fy 60ksi Es 29000ksi

Specified minimum yield strength Modulus of elasticity (5.4.3.2)

A-244

6.

PERMANENT LOADS

Permanent loads or dead loads that must be considered are self-weight, diaphragms, barriers, and future wearing surface. The barrier can be cast to the beam before it is taken on sight or attached to the bridge after the joints have reached sufficient strength. Distribution of the barriers weight should be established once you decide when it would be attached to the bridge. For this example the barrier has been cast on the exterior girder in the casting yard, before shipping but after release of prestresses. Due to this the dead load is increased on the exterior girders but it eliminates the time-consuming task that would have been completed in the field.

BeamLoc 1

Location of beam within the cross-section (0 - Interior, 1 - Exterior)

Load at Release: c.DL .155kcf
Ag.DL Ag tsac S Wj 1201.25in2

Concrete density used for weight calculations Area used for weight calculations, including sacrificial thickness

wg Ag.DLc.DL 1.293klf

Uniform load due to self-weight, including sacrificial thickness

Lg L 2Lend 44ft

Mgr(x)

wgx 2

Lg



x

Vgr(x)

wg



Lg 2



x

Span length at release Moment due to beam self-weight (supported at ends) Shear due to beam self-weight (supported at ends)

Load at Erection:

Mg(x)

wgx (L x) 2

Vg(x)

wg



L 2



x

Moment due to beam self-weight Shear due to beam self-weight

wbar 0.430klf

Uniform load due to barrier weight, exterior beams only

wbar if BeamLoc = 1 wbar0 0.43klf Redfine to 0 if interior beam (BeamLoc = 0)

Mbar(x)

wbarx (L x) 2

Vbar(x)

wbar



L 2



x

Moment due to beam self-weight Shear due to beam self-weight

A-245

6.

PERMANENT LOADS (cont'd)

Load at Service:

pfws 25psf

wfws pfwsS 0.198klf

Mfws(x)

wfwsx (L x) 2

Vfws(x)

wfws



L 2



x

wj Wjd7c.DL 0.052klf

Mj(x)

wjx (L x) 2

Vj(x)

wj



L 2



x

Assumed weight of future wearing surface Uniform load due to future wearing surface Moment due to future wearing surface Shear due to future wearing surface
Uniform load due to weight of longitudinal closure joint Moment due to longitudinal closure joint Shear due to longitudinal closure joint

A-246

7.

PRECAST LIFTING WEIGHT

For Accelerated Bridge Construction the beams are casted in a factory and transported to the job site. When they arrive at the site they must be lifted and put into place. When designing we have to consider the weight of each slab to insure safety and design for possible cracking.

Precast Superstructure
Wg wg wbar Lg 75.8kip

Substructure Precast with Superstructure

Lcorb 1ft

Bcorb bf

bf 89.25in

Dcorb 1.5ft Vcorb LcorbBcorbDcorb

11.16ft3

Precast girder, including barrier if necessary
Length of approach slab corbel Width of corbel cast with girder Average depth of corbel Volume of corbel

Lia 2.167ft

Length of integral abutment

Lgia 1.167ft

Length of girder embedded in integral abutment

Bia S Wj 7.438ft

Width of integral abutment cast with girder

Dia h 4in 44.5in
Via Vcorb LiaBiaDia Ag tflangebf Lgia

68.42ft3

Depth of integral abutment Volume of integral abutment cast with girder

Wia Viac 10kip

Weight of integral abutment cast with girder

Lsa 2.167ft

Length of semi-integral abutment

Lgsa 4in

Length of girder embedded in semi-integral abutment

Bsa S Wj 7.438ft

Width of semi-integral abutment cast with girder

Dsa h 16in 56.5in
Vsa Vcorb LsaBsaDsa Ag tflangebf Lgsa

Depth of semi-integral abutment 86.33ft3 Volume of semi-integral abutment cast with girder

Wsa Vsac 13kip

Weight of semi-integral abutment cast with girder

A-247

Semi-Integral Abutment Backwall

Integral Abutment Backwall

A-248

8.

LIVE LOAD

When considering Live Loads you must refer to the vertical load section HL-93 in the AASHTO manual. If the project you are working on requires the bridge to support construction loads at any stage, these loads must be considered separately and applied. The longitudinal joints are designed for full moment connections so the beams will act as a unit when sufficiently connected. The distribution factors are then computed for cross-section type "j" (defined in AASHTO 4.6.2.2). When calculating the stiffness parameter, the constant- depth region at the top flange is treated like the slab and the remaining area of the beam will be considered a non-composite beam.

Definitions:

Ibb

=

Abb

=

ybb

=

ts

=

moment of inertia of section below the top flange area of beam section below the top flange distance of top fiber below the top flange from neutral axis thickness of slab not including sacrificial thickness

Distribution Factors for Moment: From Table 4.6.2.2.2b-1 for moment in interior girders,

Ibb 44410in4

Abb 398in2

eg

h





tsac



ts 2



ybb

22.886 in

Kg 1.0Ibb Abbeg2 252876in4

Moment of inertia of section below the top flange Area of beam section below the top flange Distance between c.g.'s of beam and flange Longitudinal stiffness parameter (Eqn. 4.6.2.2.1-1)

Verify this girder design is within the range of applicability for Table 4.6.2.2.2b-1.
CheckMint if (S d 16ft)(S t 3.5ft)ts t 4.5in ts d 12.0in (L t 20ft)(L d 240ft) "OK" "No Good" CheckMint if (CheckMint = "OK" )Ng t 4 Kg t 10000in4Kg d 7000000in4 "OK" "No Good"
CheckMint "OK"

gmint1

0.06





S 14

ft



0.4



S L



0.3



Kg 0.1 Lts3

0.552

gmint2

0.075





S 9.5ft



0.6

S L



0.2

Kg 0.1 Lts3

0.727

gmint max gmint1gmint2 0.727

Single loaded lane Two or more loaded lanes Distribution factor for moment at interior beams

A-249

8.

LIVE LOAD (cont'd)

From Table 4.6.2.2.2d-1 for moment in exterior girders,

de

S 2



Wb

29.625 in

Distance from centerline of exterior beam to edge of curb or barrier

CheckMext if de t 1ft de d 5.5ft Ng t 4 "OK" "No Good" "OK"

For a single loaded lane, use the Lever Rule.

gmext1

S 0.5bf Wb 5ft S

0.65

em

0.77 de 9.1ft

1.041

gmext2 emgmint 0.757

gmext max gmext1gmext2 0.757

Single loaded lane Correction factor for moment (Table 4.6.2.2.2d-1) Two or more loaded lanes Distribution factor for moment at exterior beams

Distribution Factors for Shear: From Table 4.6.2.2.3a-1 for shear in interior girders,
Verify this girder design is within the range of applicability for Table 4.6.2.2.3a-1.
CheckVint if (S d 16ft)(S t 3.5ft)ts t 4.5in ts d 12.0in (L t 20ft)(L d 240ft) "OK" "No Good" CheckVint if (CheckMint = "OK" )Ng t 4 "OK" "No Good"
CheckVint "OK"

gvint1

0.36





S 25ft



0.678

gvint2

0.2





S 12ft







S 35ft



2.0

0.81

gvint max gvint1 gvint2 0.81

Single loaded lane Two or more loaded lanes Distribution factor for shear at interior beams

A-250

8.

LIVE LOAD (cont'd)

From Table 4.6.2.2.3b-1 for shear in exterior girders,

For a single loaded lane, use the Lever Rule.

CheckVext if de t 1ft de d 5.5ft Ng t 4 "OK" "No Good" "OK"

g1

S 0.5bf Wb 5ft S

0.65

ev

0.6 de 10ft

0.847

g2 evgvint 0.686

gvext max g1g2 0.686

Single loaded lane (same as for moment) Correction factor for shear (Table 4.6.2.2.3b-1) Two or more loaded lanes Distribution factor for shear at exterior beams

From Table 4.6.2.2.3c-1 for skewed bridges,

skew 0deg
CheckSkew if ( d 60deg)(3.5ft d S d 16ft)(20ft d L d 240ft) Ng t 4 "OK" "No Good" "OK"

cskew

1.0



0.20

Lts3 Kg



0.3

tan(

)

1.00

Correction factor for skew

A-251

8.

LIVE LOAD (cont'd)

Design Live Load Moment at Midspan:

wlane 0.64klf

Design lane load

Ptruck 32kip

Design truck axle load

IM 33%

Dynamic load allowance (truck only)

Mlane(x)

wlanex (L x) 2

(x) xL x2 L

Design lane load moment Influence coefficient for truck moment calculation

Mtruck(x)

Ptruck(x)max9x(L

x) 14ft(3x 4x(L x)



L)

9(

L x) 84 4(L x)

ft

Design truck moment

MHL93(x) Mlane(x) (1 IM)Mtruck(x)

HL93 design live load moment per lane

Mll.i(x) MHL93(x)gmint

Design live load moment at interior beam

Mll.e(x) MHL93(x)gmext
Mll(x) if BeamLoc = 1 Mll.e(x) Mll.i(x)

Design live load moment at exterior beam Design live load moment

Design Live Load Shear:

Vlane(x)

wlane



L 2



x

Vtruck(x)

Ptruck

9L



9x 4L

84ft



VHL93(x) Vlane(x) (1 IM)Vtruck(x)

Vll.i(x) VHL93(x)gvint

Vll.e(x) VHL93(x)gvext
Vll(x) if BeamLoc = 1 Vll.e(x) Vll.i(x)

Design lane load shear Design truck shear HL93 design live load shear Design live load shear at interior beam Design live load shear at exterior beam Design live load shear

A-252

9.

PRESTRESS PROPERTIES

Due to tension at the surface limit state be reduced to account for camber leveling forces, the prestress force required at the midspan is expected to be excessive at the ends when released. Not measuring the reduction of prestress moments. Estimate prestress losses at the midspan to find trial prestress forces, that will occur in the bottom tension fibers, that are less than allowable. Compute immediate losses in the prestressed steel and check released stresses at the end of the beam. Once you satisfy end stresses, estimate total loss of prestress. As long as these losses are not drastically different from the assumed stresses, the prestress layout should be acceptable. Concrete stress at all limit states are in Section 9.

yp.est 5in ycgp.est ybg yp.est 22.31in fp.est 25%

Assumed distance from bottom of beam to centroid of prestress at midspan Eccentricity of prestress from neutral axis, based on assumed location Estimate of total prestress losses at the service limit state

Compute bottom fiber service stresses at midspan using gross section properties.

X L 2
Mdl.ser Mg(X) Mfws(X) Mj(X) Mbar(X) 395kipft

Distance from support Total dead load moment

fb.serIII

Mdl.ser 0.8Mll(X) Sbg

fpj fpbt.max 202.5ksi

1.487ksi

Total bottom fiber service stress Prestress jacking force

fpe.est fpj 1 fp.est 151.9ksi

Estimate of effective prestress force

Aps.est

fb.serIII ft.all.ser





Ag

1

fpe.est Agycgp.est



Sbg

Nps.est

Aps.est

ceil



Ap

16

2.307in2

Estimated minimum area of prestressing steel Estimated number of strands required

Nps 38

Number of strands used ( Nps.max 40 )

The number above is used for the layout strand pattern and to compute the actual location of the strand group. After this is done the required area is computed again. If the estimated location is accurate the number of strands should be equal to the number of strands that we calculated above. The number of strands that was estimated was based on our assumed prestressed losses and gross section properties, which may not accurately reflect the final number of strands required for the design. These stresses for concrete are evaluated in Section 10. The geometry is assuming a vertical spacing of 2" between straight spans, as well as 2" for harped strands at the end of the beam. Harped strands are bundled at the midspan where the centroid is 5" from the bottom.

A-253

9.

PRESTRESS PROPERTIES (cont'd)

Nh 2 if Nps d 12 4 if 12 Nps d 24 6 if 24 Nps d 30
6 Nps 30 if Nps ! 30

Nh.add 16

Nh

min

Nh



Nh.add

16

2



floor

Nps 4

yh

1in (2in)1 0.5Nh 1



2

yhb 5in

Ns Nps Nh

Nh 14

Assumes all flange rows are filled prior to filling rows in web above the flange, which maximized efficiency. Use override below to shift strands from flange to web if needed to satisfy end stresses.

Nh 16

Additional harped strands in web (strands to be moved from flange to web)
16 strands or half of total strands maximum harped in web

yh 10in Ns 22

Centroid of harped strands from bottom, equally spaced Centroid of harped strands from bottom, bundled
Number of straight strands in flange

ys 1in 2in if Ns d 10

ys 4.273in Centroid of straight strands from bottom

(4in)Ns 20in Ns

if 10 Ns d 20

(6in)Ns 60in Ns

if 20 Ns d 24

3.5in otherwise

yp

Nsys Nhyhb Ns Nh

4.579in

Centroid of prestress from bottom at midspan

ycgp ybg yp 22.73in

Aps.req

fb.serIII ft.all.ser





Ag

fpe.est 1 Agycgp



Sbg

2.273in2

Eccentricity of prestress from neutral axis Estimated minimum area of prestressing steel

Nps.req

Aps.req

ceil

15

Ap

Estimated number of strands required

CheckNps if Nps d Nps.max Nps.req d Nps "OK" "No Good" "OK"

Aps.h NhAp 2.448in2 Aps.s NsAp 3.366in2 Aps Aps.h Aps.s 5.814in2

Area of prestress in web (harped) Area of prestress in flange (straight) Total area of prestress

A-254

9.

PRESTRESS PROPERTIES (cont'd)

Compute transformed section properties based on prestress layout.
Transformed Section Properties

Initial Transformed Section (release):

Final Transformed Section (service):

Ati 1140.4in2 Ixti 196354in4 ytti 12.756in ycgpi 22.165in ybti 26.744in

Stti 15393in3 Scgpi 8859in3 Sbti 7342in3

Atf 1136.7in2 Ixtf 194576in4 yttf 12.686in ycgpf 22.235in ybtf 26.814in

Sttf 15338in3 Scgpf 8751in3 Sbtf 7257in3

Determine initial prestress force after instantaneous loss due to elastic shortening. Use transformed properties to compute stress in the concrete at the level of prestress.

Pj fpjAps 1177.3kip

fcgpi

Pj



1 Ati



ycgpi
Scgpi



Mgr

Lg 2



Scgpi

3.554ksi

Jacking force in prestress, prior to losses
Stress in concrete at the level of prestress after instantaneous losses

fpES npifcgpi 20.886ksi

Prestress loss due to elastic shortening (5.9.5.2.3a-1)

fpi fpj fpES 181.614ksi

Initial prestress after instantaneous losses

Pi fpiAps 1055.9kip

Initial prestress force

Determine deflection of harped strands required to satisfy allowable stresses at the end of the beam at release.

fc.all.rel 0.6fci 3.84ksi
ft.all.rel max 0.0948 fciksi0.2ksi 0.200ksi

Lt 60dps 2.5ft

ycgp.t ycgp.b




ft.all.rel



Mgr Lt Stti



Pi





1 Ati





Stti




fc.all.rel



Mgr Lt Sbti



Pi





1 Ati





Sbti

17.176 in 21.025 in

Allowable compression before losses (5.9.4.1.1) Allowable tension before losses (Table 5.9.4.1.2-1) Transfer length (AASHTO 5.11.4.1) Prestress eccentricity required for tension
Prestress eccentricity required for compression

A-255

9.

PRESTRESS PROPERTIES (cont'd)

ycgp.req max ycgp.t ycgp.b 17.176in

Required prestress eccentricity at end of beam

yh.brg.req

ycgp.req ybti Ns Nh ysNs Nh

ytop.min 18in

16.848 in

hd 0.4

Minimum distance to harped prestress centroid from bottom of beam at centerline of bearing
Minimum distance between uppermost strand and top of beam
Hold-down point, fraction of the design span length

slopemax

if

dps

=

0.6in 1 12

1 8



0.125

yh.brg

h



ytop.min





0.5Nh 2



1 (2in)

15.5 in

yh.brg min yh.brgyhb slopemaxhdL 15.5in

Maximum slope of an individual strand to limit hold-down force to 4 kips/strand
Set centroid of harped strands as high as possible to minimize release and handling stresses
Verify that slope requirement is satisfied at uppermost strand

CheckEndPrestress if yh.brg t yh.brg.req"OK" "Verify release stresses." "Verify release stresses."

yp.brg

Nsys Nhyh.brg Ns Nh

9 in

Centroid of prestress from bottom at bearing

slopecgp

yp.brg yp hdL

0.023

Slope of prestress centroid within the harping length

ypx(x)

yp slopecgp Lend hdL x if x d Lend hdL
yp otherwise

Distance to center of prestress from the bottom of the beam at any position

A-256

10. PRESTRESS LOSSES

Prestressed losses can be evaluated like regular concrete, in short-term and long-term losses. When the beam is a pretension girder there are instantaneous losses when the beam is shortened upon release of the prestress forces. Time-dependent losses happen when the beam is under creep and shrinkage of the beam concrete, creep and shrinkage o the deck concrete, and the relaxation of prestressed steel. These long term effects are separated into two stages that represent significant events in bridge construction. The first stage is the time between transfer of the prestress forces and placement of the decked beam and the second is the period of time between placement of the deck and the final service load. For decked beams the computation of long-term losses is slightly simplified due to the cross-section not changing between the two stages and the shrinkage term of the deck concrete is eliminated since the deck and beam being cast together. No losses or gains in the steel associated with deck placement after transfer.

AASHTO methods for estimating time-dependent losses: Approximate Estimate (5.9.5.3) Refined Estimate (5.9.5.4)

The Approximate method is based on systems with composite decks and is based on the following assumptions: timing of load application, the cross-section in which the load is applied, and the ratio of dead and live loads to the total load. The conditions for the beams to be fabricated, formed and loaded depend on conditions assumed in the development of the approximate method. The refined method is used to estimate time-dependent losses in the prestressed steel.

Equations 5.9.5.4 are time-dependent and calculate the age-adjustment factors that effect losses using gross section properties.

ti 1 tb 20 td 30 tf 20000

Time (days) between casting and release of prestress Time (days) to barrier casting (exterior girder only) Time (days) to erection of precast section, closure joint pour Time (days) to end of service life

Terms and equations used in the loss calculations:

KL 45

VS Ag 3.911in Peri

ks

max1.45



0.13

VS in

1.0

1.00

khc 1.56 0.008H 1.00

Prestressing steel factor for low-relaxation strands (C5.9.5.4.2c) Volume-to-surface ratio of the precast section
Factor for volume-to-surface ratio (5.4.2.3.2-2)
Humidity factor for creep (5.4.2.3.2-3)

khs 2.00 0.014H 1.02

kf

5 1 fci

ksi

0.676

Humidity factor for shrinkage (5.4.2.3.3-2) Factor for effect of concrete strength (5.4.2.3.2-4)

A-257

10. PRESTRESS LOSSES (cont'd)

ktd(t)

t 61 4 fci t
ksi

t tinit 1.9kskhckfktd(t) tinit 0.118

sh(t) kskhskfktd(t) 0.4810 3

Time development factor (5.4.2.3.2-5)
Creep coefficient (5.4.2.3.2-1) Concrete shrinkage strain (5.4.2.3.3-1)

Time from Transfer to Erection:

epg yp ybg 22.73in

Eccentricity of prestress force with respect to the neutral axis of the gross non-composite beam, positive below the beam neutral axis

fcgp

Pi



1 Ag



epg2 Ixg



Mg

L 2

Ixg



yp



ybg

3.558ksi

Stress in the concrete at the center prestress immediately after transfer

fpt max fpi0.55fpy 181.614ksi

Stress in strands immediately after transfer (5.9.5.4.2c-1)

bid tdti 0.589 bif tf ti 1.282 bid sh td ti 1.490 u 10 4

Creep coefficient at erection due to loading at transfer Creep coefficient at final due to loading at transfer Concrete shrinkage between transfer and erection

Kid

1

1



npi

Aps Ag





1



Agepg2 Ixg





1



0.7bif

0.805

Age-adjusted transformed section coefficient (5.9.5.4.2a-2)

fpSR bidEpKid 3.418ksi

Loss due to beam shrinkage (5.9.5.4.2a-1)

fpCR npifcgpbidKid 9.913ksi

fpR1



fpt



log

KL log

24td 24ti





fpt

fpy



0.551




3

fpSR fpt

fpCR

Kid

1.035ksi

Loss due to creep (5.9.5.4.2b-1)
Loss due to relaxation (C5.9.5.4.2c-1

fpid fpSR fpCR fpR1 14.366ksi

A-258

10. PRESTRESS LOSSES (cont'd)

Time from Erection to Final: epc epg 22.73in

Ac Ag

Ic Ixg

fcd

Mfws

L 2





Mj

L 2





fpid

Scgpf

np

2.665ksi

bdf tf td 0.858

bif sh tf ti 3.302 u 10 4

bdf bif bid 1.813 u 10 4

Eccentricity of prestress force does not change Section properties remain unchanged
Change in concrete stress at center of prestress due to initial time-dependent losses and superimposed dead load. Deck weight is not included for this design. Creep coefficient at final due to loading at erection
Concrete shrinkage between transfer and final
Concrete shrinkage between erection and final

Kdf

1

1



n

pi

Aps Ac



1



Acepc2 Ic





1

0.7bif

0.805

Age-adjusted transformed section coefficient remains unchanged

fpSD bdfEpKdf 4.159ksi

Loss due to beam shrinkage

fpCD npifcgp bif bid Kdf npfcdbdfKdf 21.331ksi

Loss due to creep

fpR2 fpR1 1.035ksi

Loss due to relaxation

fpSS 0

Loss due to deck shrinkage

fpdf fpSD fpCD fpR2 fpSS 26.525ksi

Prestress Loss Summary fpES 20.886ksi fpLT fpid fpdf 40.891ksi fpTotal fpES fpLT 61.777ksi

fpES fpj

10.3 %

fpLT fpj

20.2 %

fpTotal fpj

30.5 %

fpe fpj fpTotal 140.7ksi

CheckFinalPrestress if fpe d fpe.max"OK" "No Good" "OK"

fp.est 25% Final effective prestress

A-259

11. CONCRETE STRESSES

Concrete Stresses at release, during handling and at final service are computed and compared to approximated values for each stage.

Concrete Stresses at Release

When calculating the stresses at release use the overall beam length due to the beam being supported at each end in the casting bed after prestress forces are transformed.

Define locations for which stresses are to be calculated:

xr

Lg 0


min

Lt

Lend



Lg Lg

max

Lt

Lend



Lg Lg

T 0.1 0.2 0.3 hd 0.5


ir 1 lastxr

Functions for computing beam stresses:

ftop.r(x)

min

x Lt

1



Pi



1 Ati



ybti

ypx(x)



Stti





Mgr(x) Stti

fbot.r(x)

min

x Lt

1



Pi



1 Ati



ybti

ypx(x)
Sbti



Mgr(x) Sbti

Top fiber stress at release Bottom fiber stress at release

4

ftop.r( x) ksi 3

fbot.r( x)
ksi 2
fc.all.rel
ksi 1
ft.all.rel
ksi

0

0

Stresses in Concrete at Release (Half Beam)

Stress (ksi)

1

0

3

6

9

12

15

18

21

24

27

30

x

ft

Distance along Beam (ft)

A-260

11. CONCRETE STRESSES (cont'd) Compare beam stresses to allowable stresses.
ft.all.rel 0.2ksi

Allowable tension at release

fc.all.rel 3.84ksi

Allowable compression at release

TopRelir ftop.r xrir

TopRelT ( 0.000 0.191 0.248 0.249 0.264 0.299 0.353 0.351 )ksi

CheckTopRel if max(TopRel) d fc.all.rel min(TopRel) t ft.all.rel "OK" "No Good" "No Good"

BotRelir fbot.r xrir

BotRelT ( 0.000 2.693 3.388 3.389 3.421 3.493 3.607 3.602 )ksi

CheckBotRel if max(BotRel) d fc.all.rel min(BotRel) t ft.all.rel "OK" "No Good" "OK"

Concrete Stresses During Lifting and Transportation

Lifting and transportation stresses can govern over final stresses due to different support locations, dynamic effects that dead load can cause during movement, bending stresses during lifting and superelevation of the roadway in shipping. End diaphragms on both ends are assumed. For prestressing effects, calculate the effective prestressed force losses between transfer and building.

a h 3.375ft

Maximum distance to lift point from bearing line

a' a Lend 5.375ft

Distance to lift point from end of beam

Pdia max WiaWsa 12.9kip

Pm

Pj1


fpES fpid



fpj



972.4kip

Approximate abutment weight Effective prestress during lifting and shipping

Define locations for which stresses are to be calculated:

xe

Lg 0


min

Lt

Lend



Lg Lg

max

Lt

Lend



Lg Lg

a' Lg

T hd 0.5


ie 1 lastxe

Compute moment in the girder during lifting with supports at the lift points.

Mlift(x)




wg



wbar 2

x2





Pdia

x

if

x d a'


Mgr(x) Mgr(a')

wg



wbar 2

(a')2





Pdia

a'

otherwise

A-261

11. CONCRETE STRESSES (cont'd) Functions for computing beam stresses:

ftop.lift(x)

min

x Lt

1



Pm



1 Atf



ybtf

ypx(x)



Sttf





Mlift(x) Sttf

ftop.DIM.inc(x)

min

x Lt

1



Pm



1 Atf



ybtf

ypx(x)



Sttf





Mlift(x) (1 Sttf



DIM)

ftop.DIM.dec(x)

min

x Lt

1



Pm



1 Atf



ybtf

ypx(x)



Sttf





Mlift(x) (1 Sttf



DIM)

Top fiber stress during lifting
Top fiber stress during lifting, impact increasing dead load
Top fiber stress during lifting, impact decreasing dead load

TopLift1ie TopLift2ie TopLift3ie

ftop.lift xeie ftop.DIM.inc xeie ftop.DIM.dec xeie

TopLift1T ( 0.000 0.242 0.312 0.407 0.491 0.488 )ksi TopLift2T ( 0.000 0.249 0.321 0.429 0.474 0.469 )ksi TopLift3T ( 0.000 0.235 0.303 0.385 0.508 0.508 )ksi

fbot.lift(x)

min

x Lt

1



Pm



1 Atf



ybtf

ypx(x)



Sbtf





Mlift(x) Sbtf

fbot.DIM.inc(x)

min

x Lt

1



Pm



1 Atf



ybtf

ypx(x)



Sbtf





Mlift(x) (1 Sbtf



DIM)

fbot.DIM.dec(x)

min

x Lt

1



Pm



1 Atf



ybtf

ypx(x)



Sbtf





Mlift(x) (1 Sbtf



DIM)

Bottom fiber stress during lifting
Bottom fiber stress during lifting, impact increasing dead load
Bottom fiber stress during lifting, impact decreasing dead load

BotLift1ie BotLift2ie BotLift3ie

fbot.lift xeie fbot.DIM.inc xeie fbot.DIM.dec xeie

BotLift1T ( 0.000 2.643 3.323 3.524 3.702 3.696 )ksi BotLift2T ( 0.000 2.657 3.342 3.571 3.666 3.654 )ksi BotLift3T ( 0.000 2.628 3.305 3.477 3.737 3.737 )ksi

Allowable stresses during handling:
fcm fc.erec fc 7.2ksi
fc.all.erec 0.6fcm 4.32ksi
ft.all.erec ft.erec fcm 0.429ksi

Assumed concrete strength when handling operations begin Allowable compression during lifting and shipping Allowable tension during lifting and shipping

A-262

11. CONCRETE STRESSES (cont'd) Stresses in Concrete During Lifting (Half Beam)

Stress (ksi)

ftop.lift( x) ksi

ftop.DIM.inc(x) 4 ksi

ftop.DIM.dec( x) ksi

fbot.lift( x) ksi

fbot.DIM.inc ( x)

ksi

2

fbot.DIM.dec( x) ksi

fc.all.erec ksi

ft.all.erec
ksi 0
0

0

3

6

9

12

15

18

21

24

27

30

x

ft

Distance along Beam (ft)

Compare beam stresses to allowable stresses.

TopLiftMaxie max TopLift1ie TopLift2ie TopLift3ie

TopLiftMaxT ( 0 0.235 0.303 0.385 0.474 0.469 )ks

TopLiftMinie min TopLift1ie TopLift2ie TopLift3ie

TopLiftMinT ( 0 0.249 0.321 0.429 0.508 0.508 )ks

CheckTopLift if max(TopLiftMax) d fc.all.erec min(TopLiftMin) t ft.all.erec "OK" "No Good" "No Goo

BotLiftMaxie max BotLift1ie BotLift2ie BotLift3ie

BotLiftMaxT ( 0 2.657 3.342 3.571 3.737 3.737 )ksi

BotLiftMinie min BotLift1ie BotLift2ie BotLift3ie

BotLiftMinT ( 0 2.628 3.305 3.477 3.666 3.654 )ksi

CheckBotLift if max(BotLiftMax) d fc.all.erec min(BotLiftMin) t ft.all.erec "OK" "No Good" "OK"

A-263

11. CONCRETE STRESSES (cont'd)

Concrete Stresses at Final

Stresses are calculated using design span length. The top flange compression and bottom flange under tension are computed at Service I and Service III states.

fc.all.ser1 0.4fc 3.2ksi fc.all.ser2 0.6fc 4.8ksi

Allowable compression due to effective prestress and dead load (Table 5.9.4.2.1-1)
Allowable compression due to effective prestress, permanent load, and transient loads, as well as stresses during shipping and handling (Table 5.9.4.2.1-1)

ft.all.ser 0ksi

Allowable tension (computed previously)

Pe fpeAps 818.2kip

Effective prestress after all losses

Compute stresses at midspan and compare to allowable values.

ftop.ser1(x)

Lend min
Lt

x

1




Pe



1 Atf



ybtf

ypx(x)



Sttf





Mg

x Lend Stti

Mbar(x) Mfws(x) Mj(x) Sttf

ftop.ser2(x)

Lend min
Lt

x

1




Pe



1 Atf



ybtf

ypx(x)



Sttf





Mg

x Lend Stti

Mbar(x) Mfws(x) Mj(x) Mll(x) Sttf

fbot.ser(x)

Lend min
Lt

x

1




Pe



1 Atf



ybtf

ypx(x)



Sbtf





Mg

x Lend Sbti

Mbar(x) Mfws(x) Mj(x) 0.8Mll(x) Sbtf

Stresses in Concrete at Service (Half Beam) 6

ftop.ser1( x) ksi
ftop.ser2( x) ksi 4

Stress (ksi)

fbot.ser( x) ksi
ft.all.ser ksi 2
fc.all.ser1 ksi
fc.all.ser2 ksi 0

0

3

6

9

12

15

18

21

24

27

30

x

ft

Distance along Beam (ft)

A-264

11. CONCRETE STRESSES (cont'd)

Compare beam stresses to allowable stresses.

xs

L Lt L

0.1

0.15

0.2

0.25

0.3

0.35

hd

0.45

0.5 T

is 1 lastxs

TopSer1is ftop.ser1 xsis TopSer2is ftop.ser2 xsis

TopSer1T TopSer2T

( 0.132 0.119 0.106 0.100 0.099 0.105 0.117 0.135 0.159 0 ( 0.015 0.060 0.142 0.206 0.250 0.276 0.287 0.288 0.270 0.262 )ksi

CheckCompSerI if max(TopSer1) d fc.all.ser1 max(TopSer2) d fc.all.ser2 "OK" "No Good" "OK"

BotSeris fbot.ser xsis

BotSerT ( 2.324 2.192 2.048 1.938 1.862 1.822 1.809 1.815 1.856 1.870 )ksi

CheckTenSerIII if min(BotSer) t ft.all.ser"OK" "No Good" "OK"

12. FLEXURAL STRENGTH

Confirm flexural resistance at Strength Limit State. Calculate Factored moment at midspan during Strength I load combination. Compare this to factored resistance in AASHTO LRFD 5.7.3.

MDC(x) Mg(x) Mbar(x) Mj(x)

Self weight of components

MDW(x) Mfws(x)

Weight of future wearing surface

MLL(x) Mll(x)

Live load

MStrI(x) 1.25MDC(x) 1.5MDW(x) 1.75MLL(x)

Factored design moment

For minimum reinforcement check, per 5.7.3.3.2

fcpe

Pe



1 Ag



ycgp
Sbg

3.525ksi

Mcr fr.cm fcpe Sbg 2540kipft

Mu(x) max MStrI(x) min 1.33MStrI(x) 1.2Mcr

Concrete compression at extreme fiber due to effective prestress Cracking moment (5.7.3.3.2-1)
Design moment

A-265

12. FLEXURAL STRENGTH (cont'd)

Compute factored flexural resistance.

1

max0.650.85 0.05 fc 4



ksi

k

21.04



fpy

0.28



fpu

dp(x) h ypx x Lend

0.65 dp(X)

35.921 in

hf d7 8in

btaper

b6 b5 2

16 in

htaper d5 2in

a(x) c(x)

Apsfpu

0.85fcbf



k 1



Aps



fpu dp(x)



a(x)

1

a(X) 2.509in c(X) 3.86in

CheckTC

if dcp((XX))

d



.003 .003 .005



"OK"

"NG"

"OK"

Stress block factor (5.7.2.2)
Tendon type factor (5.7.3.1.1-2) Distance from compression fiber to prestress centroid Structural flange thickness Average width of taper at bottom of flange Depth of taper at bottom of flange Depth of equivalent stress block for rectangular section
Neutral axis location
Tension-controlled section check (midspan)

f

min1.0max0.750.583 0.25 dp(X) 1





c(X)

1.00

Resistance factor for prestressed concrete (5.5.4.2)

fps

fpu1



k

c(X) dp(X)



261.9ksi

Average stress in the prestressing steel (5.7.3.1.1-1)

Ld

1.6 ksi





fps



2 3



fpe



dps

11.204 ft

Bonded strand devlepment length (5.11.4.2-1)

fpx(x)

fpe x Lend
Lt

if x d Lt Lend

Stress in prestressing steel along the length for bonded strand (5.11.4.2)

fpe

x

Lend Ld Lt

Lt

fps



fpe

if Lt Lend x d Ld Lend

fps otherwise

Mr(x)

fApsfpx(x)dp(x)



a(x) 2



Flexure resistance along the length

A-266

12. FLEXURAL STRENGTH (cont'd)

xmom

L 0.01

Lt Lend L

Ld Lend L

hd

0.5 T

Mrximom Mr xmomimom

Muximom Mu xmomimom

imom 1 last xmom

DCmom

Mux Mrx

max DCmom 0.438

CheckMom if max DCmom d 1.0"OK" "No Good"

"OK"

Demand-Capacity ratio for moment Flexure resistance check

Design Moment and Flexure Resistance (Half Beam)

Moment (kipft)

MStrI( x) kip ft

4000

1.2 Mcr

kip ft

3000

1.33 MStrI( x)

kip ft

Mu( x)

2000

kip ft

Mr( x) kip ft

1000

0

0

3

6

9

12

15

18

21

24

27

30

x

ft

Distance along Beam (ft)

A-267

13. SHEAR STRENGTH

Shear Resistance

Use Strength I load combination to calculate factored shear at the critical shear section and at tenth points along the span. Compare it to factored resistance in AASHTO LRFD 5.8.

VDC(x) Vg(x) Vbar(x) Vj(x)

Self weight of components

VDW(x) Vfws(x)

Weight of future wearing surface

VLL(x) Vll(x)

Live load

Vu(x) 1.25VDC(x) 1.5VDW(x) 1.75VLL(x)

Factored design shear

v 0.90

Resistance factor for shear in normal weight concrete (AASHTO LRFD 5.5.4.2)

dend h ypx Lend 31.5in

Depth to steel centroid at bearing

dv min 0.9dend0.72h 28.35in

Effective shear depth lower limit at end

Vp(x)

Peslopecgp

x

Lend Lt

if x d Lt Lend

Peslopecgp if Lt Lend x d hdL

0 otherwise

bv b3 6in

vu(x)

Vu(x) vVp(x) vbvdv

Mushr(x) max MStrI(x) Vu(x) Vp(x) dv

fpo 0.7fpu 189ksi

Vertical component of effective prestress force
Web thickness Shear stress on concrete (5.8.2.9-1) Factored moment for shear Stress in prestressing steel due to locked-in strain after casting concrete

s(x)



Mu(x)

max0.410 3 dv



Vu(x) Vp(x) EpAps



Aps

fpo



Steel strain at the centroid of the prestressing

steel

(x)

4.8

1 750s(x)

(x) 29 3500s(x) deg

Shear resistance parameter Principal compressive stress angle

Vc(x)

0.0316ksi(x)

fc ksi



bv

dv

Concrete contribution to total shear resistance

A-268

13. SHEAR STRENGTH (cont'd)

90deg

Angle of inclination of transverse reinforcement

Av ( 1.02 0.62 0.62 0.62 0.31 )Tin2

sv ( 3 6 6 12 12 )Tin

Transverse reinforcement area and spacing provided

xv ( 0 0.25h 1.5h 0.3L 0.5L 0.6L )T

xvT ( 0 0.844 5.063 12 20 24 )ft

Avs(x) for i 1 last Av

out m Avi svi

if xvi d x d xvi1

.

out

Vs(x) Avs(x)fydv(cot((x)) cot())sin()

Steel contribution to total shear resistance

Vr(x) v Vc(x) Vs(x) Vp(x)

Factored shear resistance

xshr

for i 1 100

outi

m

i

0.5L 100

out

ishr 1 last xshr

Vuxishr Vu xshrishr

Vrxishr Vr xshrishr

DCshr

Vux Vrx

max DCshr 0.357

CheckShear if max DCshr d 1.0"OK" "No Good" "OK" Shear resistance check

Shear (kips)

400 Vu( x)
300 kip
Vr(x) 200
kip 100

Design Shear and Resistance (Half Beam)

0

0

3

6

9

12

15

18

21

24

27

30

x

ft

Distance along Beam (ft)

A-269

13. SHEAR STRENGTH (cont'd)

Longitudinal Reinforcement

Al.req(x)

a1 m

MStrI(x)

ffpx(x)dp(x)



a(x) 2



a2

m

Vu(x)



v



0.5Vs(x)



Vp( x) cot( ( x) )


fpx(x)

a3 m

Mushr(x) dvf




Vu(x) v



Vp(x)

0.5Vs(x)cot((x))


fpx(x)

min(a1a2) if x d dv 5in

min(a1a3) otherwise

Longitudinal reinforcement required for shear (5.8.3.5)

As.add 0.40in2

Ld.add 18.67ft

Additional longitudinal steel and developed length from end of beam

Al.prov(x)

if x Ld.add LendAs.add0

ApNs

x

Lend Ld

if x d Ld Lend

ApNs

if

Ld



Lend



x

d

yh.brg 0.5h slopecgp



0.5Nh 2



1 (2in)cot

slopecgp

Ap Nh Ns otherwise

Steel Area (in2)

6 Al.req( x)
in2 4
Al.prov( x) 2
in2
0 0

Longitudinal Reinforcement Required and Provided (Half Beam)

3

6

9

12

15

18

21

24

27

30

x

ft

Distance along Beam (ft)

Al.reqishr Al.req xshrishr

Al.provishr Al.prov xshrishr

DClong

Al.req Al.prov

max DClong 0.395

CheckLong if max DClong d 1.0"OK" "No Good" "OK"

Longitudinal reinforcement check

A-270

14. SPLITTING RESISTANCE Splitting Resistance Checking splitting by zone of transverse reinforcement. Defined in Shear Strength section.

As

Av1xv2 sv1

3.443in2

fs 20ksi

Pr fsAs 68.9kip

Pr.min 0.04Pj 47.1kip

CheckSplit if Pr t Pr.min"OK" "No Good" "OK"

Limiting stress in steel for crack control (5.10.10.1) Splitting resistance provided (5.10.10.1-1) Minimum splitting resistance required Splitting resistance check

15. CAMBER AND DEFLECTIONS Calculate Deflections due to different weights, joints, and future wearings.

ps

Pi





ycgp

Lg2



ybg



yp.brg



hdL



Lend

2

EciIxg 8

6



0.777in Deflection due to prestress at release

gr

5 wgLg4 384 EciIxg

0.123in

Deflection due to self-weight at release

bar

5 wbarLg4 384 EcIxg

0.037in

Deflection due to barrier weight

j

5 wjL4 if (BeamLoc = 0 1 0.5) 384 EcIxg

0.002in

2

Deflection due to longitudinal joint

fws

5



wfwsL4 if BeamLoc

=

S 0 1



Wb

384 EcIxg

S

0.009in

Deflection due to future wearing surface

tbar 20

Age at which barrier is assumed to be cast

T ti 7 14 21 28 60 120 240 T

Concrete ages at which camber is computed

A-271

15. CAMBER AND DEFLECTIONS (cont'd)
cr1(t) t titi gr ps

cr2(t) t titi tbar titi gr ps t tbartbar bar

cr3(t) t titi td titi gr ps t tbartbar td tbartbar bar t tdtd j

cr(t) Defl(t)

cr1(t) if t d tbar
cr1 tbar cr2(t) if tbar t d td cr1 tbar cr2 td cr3(t) if t ! td
gr ps cr1(t) if t d tbar gr ps cr1 tbar bar cr2(t) if tbar t d td gr ps cr1 tbar bar cr2 td j cr3(t) if t ! td

C for j 1 last(T)
outj m Defl Tj
out

CT ( 0.653 0.775 0.879 0.919 0.974 1.121 1.236 1.316 1.42 )in

Deflection (in)

2
cr(t) 1.5 in 1
Defl( t)
in 0.5

60-Day Deflection at Midspan

0

0

20

40

60

t

Age of Concrete (days)

Deflection (in)

2
cr(t) 1.5 in 1
Defl( t) in 0.5
0 0

Long-term Deflection at Midspan

500

1000

t

Age of Concrete (days)

1500

2000

A-272

16. NEGATIVE MOMENT FLEXURAL STRENGTH
Calculate factored moment that must be resisted across the interior pier and find required steel to be developed in the top flange.

Negative Live Load Moment
Compute the negative moment over the interior support due to the design live load load, in accordance with AASHTO LRFD 3.6.1.3.1.

Live Load Truck and Truck Train Moment Calculations

min Mtruck 530kipft

min Mtrain 450kipft

Mneg.lane

wlaneL2 2

512kipft

Maximum negative moment due to a single truck
Maximum negative moment due to two trucks in a single lane
Negative moment due to lane load on adjacent spans

Mneg.truck Mneg.lane (1 IM)min Mtruck 1217kipft

Live load negative moment for single truck

Mneg.train 0.9Mneg.lane (1 IM)min Mtrain 999kipft

Live load negative moment for two trucks in a single lane

MHL93.neg min Mneg.truck Mneg.train 1217kipft

Design negative live load moment, per design lane

Mll.neg.i MHL93.neggmint 884kipft Mll.neg.e MHL93.neggmext 921kipft
MLL.neg if BeamLoc = 1 Mll.neg.eMll.neg.i 921kipft

Design negative live load moment at interior beam
Design negative live load moment at exterior beam
Design negative live load moment

Factored Negative Design Moment

Dead load applied to the continuity section at interior supports is limited to the future overlay.

MDW.neg

wfwsL2 2

159kipft

Mu.neg.StrI 1.5MDW.neg 1.75MLL.neg 1850kipft

Superimposed dead load resisted by continuity section
Strength Limit State

Mu.neg.StrI 1.0MDW.neg 1.0MLL.neg 1080kipft

Service Limit State

A-273

16. NEGATIVE MOMENT FLEXURAL STRENGTH (cont'd)

Reinforcing Steel Requirement in the Top Flange for Strength

f 0.90

bc b1 26in
dnms h tsac 0.5 tflange tsac

35.5 in

Reduction factor for strength in tensioncontrolled reinforced concrete (5.5.4.2)
Width of compression block at bottom flange
Distance to centroid of negative moment steel, taken at mid-depth of top flange

Ru

Mu.neg.StrI

f



bcd

2
nms

0.439ksi

m

fy

8.824

0.85fc

req

1

1



m

1



2

m

Ru



fy

0.0076

Anms.req reqbcdnms 6.992in2

As.long.t 2.0in2

As.long.b 2.0in2

Abar 0.44in2

Anms.t

2 3

Anms.req



As.long.t

nbar.t

Anms.t

ceil



Abar

7

2.661in2

Anms.b

1 3

Anms.req



As.long.b

nbar.b

Anms.b

ceil



Abar

1

0.331in2

sbar.top

S Wj 6in nbar.t 1

13.875 in

As.nms nbar.t nbar.b Abar As.long.t As.long.b

7.52 in2

a As.nmsfy 2.552in 0.85fcbc

Mr.neg

fAs.nmsfydnms



a 2



1158kipft

DCneg.mom

Mu.neg.StrI Mr.neg

0.932

CheckNegMom if DCneg.mom d 1.0"OK" "No Good"

"OK"

Factored load, in terms of stress in concrete at depth of steel, for computing steel requirement Steel-to-concrete strength ratio
Required negative moment steel ratio
Required negative moment steel in top flange Full-length longitudinal reinforcement to be made continuous across joint Additional negative moment reinforcing bar area Additional reinforcement area required in the top mat (2/3 of total) Additional bars required in the top mat
Additional reinforcement area required in the bottom mat Additional bars required in the top mat
Spacing of bars in top mat
Total reinforcing steel provided over pier
Depth of compression block
Factored flexural resistance at interior pier
Negative flexure resistance check

A-274

APPENDIX C ABC CONSTRUCTION PRACTICE
FLOWCHARTS
A-275

APPENDIX C - ABC CONSTRUCTION PRACTICE FLOWCHARTS A-276

APPENDIX D RISK ANALYSIS EXAMPLES AND
INTERACTIVE FLOWCHART
A-277

APPENDIX D - RISK ANALYSIS EXAMPLES AND INTERACTIVE FLOWCHART
Example Problem 1:
As part of project involving the reconstruction of a portion of a state owned roadway, officials from Floyd County are considering replacing the three (3) 42" multi-barrel corrugated steel pipe culverts with larger size culverts. Rather than manually delineating the watershed, they use the USGS StreamStats application which reveals that the drainage area is 0.21miles2 (134 acres), 3.5% of which is impervious (see Figure 1).

Figure 1. Output from USGS StreamStats Application

Using the USGS regression equations shown in Table 1 for a 50 year return period within Region 1, the
peak flow is calculated to be: Qp = 661(DA)0.600 = 661 (.21)0.600 = 259. 14 ft3/s

Computing the waterway area for V = 3 ft/s and 5 ft/s yields:

V = 3 ft/s:

.

/

/

V = 5 ft/s:

.

/

/

86.38 51.83

Based on the area information shown in Table 5, a single corrugated pipe culvert would have a size of 126" (for V = 3 ft/s) or 102" (for V = 5 ft/s). Using the more conservative size (126"), Table 7 indicates that the county could replace the existing culverts with three (3) 78" or four (4) 66" multi-barrel culverts.

A-278

Example Problem 2:
County officials from the same county (Floyd) are examining another state roadway project in which a single 4' x 4' concrete box culvert might have to be replaced. The location of the culvert is in an urbanized area with a total area of 0.125 miles2 (80 acres). A site investigation reveals that the area is predominately flat, with 30% (24 acres) single family residential, 25% (20 acres) apartment homes, 35% (28 acres) lawns (clay soil), and the remaining 10% (8 acres) woodlands and forests.

Applying the Rational Method, the runoff coefficients for a 50 year return period are:

Single family residential:

(0.30 * 1.2) = 0.36

Apartment homes:

(0.50 * 1.2) = 0.60

Lawns (clay soil):

(0.17 * 1.2) = 0.20

Woodlands and forests: (0.10 * 1.2) = 0.12

The weighted runoff coefficient is computed as follows:

0.36 24

0.60 20 0.20 28 80

0.12 8 0.34

Since the project location is near the City of Rome, the rainfall intensity data can be taken directly from Table 4:
I = 3.12 in/hr

Using the runoff coefficient, rainfall intensity, and area information, the peak flow is computed as:

Qp = CIA = (0.34) *(3.12 in/hr)*(80 acres) = 84.86 ft3/s

Computing the waterway area for V = 3 ft/s and 5 ft/s yields:

V = 3 ft/s: V = 5 ft/s:

.

/

/

.

/

/

28.29 16.97

Based on the area information shown in Table 6, a single box culvert would have a size of 6' x 5' (for V = 3 ft/s) or 6' x 3' (for V = 5 ft/s). Using the more conservative size, the county could replace the existing 4' x 4' culvert with a 6' x 5' culvert.

A-279

Risk Analysis Flowchart: A-280

APPENDIX E CONCEPTUAL COST ESTIMATES
EXAMPLES
A-281

APPENDIX E - CONCEPTUAL COST ESTIMATES EXAMPLES

Case study 1 summary - Interstate Bridge Replacement over Local Road in Urban Environment (FHWAEvery Day Counts)

Construction Type
Prefabricated

Labor ($,%, Hrs) $1,889,726
35.38% 10,4449.281
Hours

Material ($,%)
$1,887,855 35.35%

Subcontractors ($,%) $789,209 14.78%

Equipment ($,%, Hrs)
$679,331 12.72% 3,261.644 Hours

Other ($,%) $94,564 1.77%

Total ($)
$5,340,685

Conventional

$2,119,985 38.82%
21,670.339 Hours

$1,210,878 17.60%

$0.00 0%

$418,030 6.08%
2,561.883 Hours

$3,129,659 $6,878,552 45.50%

Details for the breakdown of direct cost components, quantity takeoffs and total cost/units are shown in exhibits E1 and E2. Users may refer also to the notes provided to each case study for additional information regarding durations and pricing.
Case study 2 summary - Route 10 over Passaic River Superstructure Replacement estimate report. This particular example was obtained from an experienced contractor. The cost estimate report is a detailed report of break down costs obtained by construction items assigned individually and their total units for total cost calculations on the bridge replacement job. Therefore, the job estimate report is presented as a guidance for cost estimators and it is presented in exhibit E3 of this appendix.
The responses of the special survey are attached to this Appendix E, as exhibit E4. They can be used as further guidance to potential users and to complement the decision-making matrix with inclusive items affecting directly the conceptual cost estimates. They were a total of eighteen responses collected and they are all attached to this report.
The followings are the special survey questions on conceptual cost estimates factors and cost components deployed to all state DOTs:
1) Based on your experience with ABC, are prefabricated bridges more costly than conventional bridges? 2) Have you ever used another contracting method besides Design-Bid-Build for ABC? If yes, under what circumstances? 3) What ABC elements have been more costly than conventional bridge construction? 4) Have any of your contractors had cost concerns when using ABC? 5) Did federal and/or state requirements affect the overall ABC cost/duration of the project? If yes, how? 6) What, if any, environmental factors/policies affected your ABC projects? How did these affect the overall cost?

A-282

Cost Estimating Spreadsheet Report
Prefabricated Alt. CS 1
Every Day Counts Case Study 1

Project name
Labor rate table Equipment rate table
Notes

Prefabricated Alt. CS 1 Fla.
Labor 2011
Equip 2011
1. Pricing is 2011 $. 2. Construction Schedule of 12 mos. 3. Rates reflect majority of work performed days with the exception of actual installation of bridges. 4. 2 Bridges. 5. Labor Cost/Unit - This reflects the cost of Labor to put one unit of measure of work in place. This is comprised of a typical crew with associated productivity required to perform the activity. Labor is priced up to include base rate, fringes, taxes, insurance, etc. 6. Material Cost/Unit - This cost represents the final installed cost for all the materials associated with the item of work. 7. Sub Contract Cost/Unit - this represents the Sub Contract all in Cost to put one unit of work in place. This cost includes all costs necessary to reflect a total installed cost (includes Labor, equipment and material). 8. Equipment Cost/Unit - This represents the cost of Construction Equipment necessary to put one unit of work in place. This cost includes equipment ownership and maintenance and operational costs. 9. Other Cost/Unit - This cost represents all other costs necessary to perform the item of work and not covered by the abovementioned costs. 10. Total cost/unit - This is the summation of all unit costs to arrive at a total cost per unit to put one item of work in place. 11. Total Amount - Total cost to put the quantity of units specified in place.

Page 1

A-283

Cost Estimating Spreadsheet Report
Prefabricated Alt. CS 1

Page 2

Spreadsheet Level

Takeoff Quantity

AdddditiitoionnalaCl Cosot sAtdAdidtidointaiol nCaolstCSoPsMt TS'Ps MT's

** unassssigignneded* *

011-5544--2233.0.000TTemempoproarayrSycSafcfoalfdfoinldginAgndAPnldatPfolramtfsorms

011-5544--2233.7.700SScacfafoflfdoilndging

Scaffolding, steel tubular,

300.00 csf

heavy duty shoring for elev

slab forms, floor area,

rent/month of complete

system, to 14'-8" H

Scaffolding

Temporary Scaffolding

And Platforms

0202-4-433-0-000..0000 SStruuccttuurreeMMoovviningg 022-4433--1133.1.133BBrirdidgegeReRloecloactiaotnion Remove Existing Bridges Out & Install New Bridges SPMT Remove Existing Bridges Out & Install New Bridges SPMT 2nd Bridge Bridge Relocation Structure Moving

1.00 totl 1.00 totl

322-1122--1166.0.000AAspshpahltaPlt aPvainvging

322-1122--1166.1.133PPlalnatn-Mt-MixixAsApshpahltaPltaPvianvging

Allow for additional Paving

1,000.00 ton

etc.

Plant-Mix Asphalt Paving

Asphalt Paving

322-3344--0000.0.000FFabarbirciactaetdedBrBidrgidegses 322-3344--1100.1.100BBrirdidgegse,sH, iHghigwhawyay Temporary Concrete Temporary Concrete Remove Bridges, Highway Fabricated Bridges

100.00 cy 100.00 cy

344-7711--1133.0.000VVeheihcliceleBaBrarirerries rs 344-7711--1133.1.177SeSceucruitryitVyeVheichleicBlearBraierrrsiers Jersey Barriers

64.00 ea

Labor Cost/Unit

Material Cost/Unit

Sub Cost/Unit

Equip Cost/Unit

Other Cost/Unit Total Cost/Unit

Total Amount

-

51.42

-

-

-

51.42

15,425

15,425 15,425

-

-

526,139.46

-

-

-

263,069.73

-

526,139.46 263,069.73

6.23

62.18

-

3.46

-

71.86

270.95

198.50

-

19.01

-

488.46

-

149.47

149.47

79.32

119.58

-

31.50

-

230.40

526,139
263,070 789,209 789,209
71,861 71,861 71,861
48,846 14,947 63,793 63,793
14,745

A-284

Cost Estimating Spreadsheet Report
Prefabricated Alt. CS 1

Page 3

Spreadsheet Level

Takeoff Quantity

344-7711--1133.1.177SSeceucruitryitVyeVheichleicBlearBraierrrsiers

Jersey Barriers Pier

200.00 ea

Expansion

Detour

2.00 Day

Security Vehicle Barriers

Vehicle Barriers

* unassigned *

Additional Cost

Additional Cost

SPMT's

Geenneerraal lCConodnidtiiotniosnGsenGeernaleCraolnCdiotinondsitions

** unassssigignneded* *

011-3311--0000.0.000PProrjoejcetcMt ManaangaegmeemnteAnntdACnodoCrdoinoardtiionnation

011-3311--1133.2.200FFieieldldPPeresrosnonnenl el

Field Personnel, clerk,

42.00 week

average

Field engineer, average

47.00 week

Field Personnel, project

47.00 week

manager, average

Field Personnel,

42.00 week

superintendent, average

Field Personnel

Project Management And

Coordination

011-3322--3333.0.000PPhohtootgorgarpahpichiDc oDcoumcuemnteatniotantion

011-3322--3333.5.500PPhohtootgorgarpahpshs

Construction Photographs

42.00 set

Photographs

Photographic

Documentation

0011-4-455--0000.00 QQuuaalliittyyCCoonntrtrool l 0011-4-455--2233..550 Teesstitningg Field Testing Testing Quality Control

2.00 prjc

011-5522--1133.0.000FFieiledldOOffifcfiecseAsnAdnSdheSdhseds 011-5522--1133.2.200OOfffifcieceAnAdnSdtoSrtaogreagSepaScepace

Labor Cost/Unit

Material Cost/Unit

Sub Cost/Unit

Equip Cost/Unit

Other Cost/Unit Total Cost/Unit

Total Amount

79.32 -

119.58 -

-

31.50

-

230.40

46,080

-

-

3,826.47

3,826.47

7,653

68,478

68,478

1,008,766

1,008,766

436.46
1,345.24 2,212.18
2,032.81

-

-

-

-

436.46

18,331

-

-

-

-

1,345.24

63,226

-

-

-

-

2,212.18

103,972

-

-

-

-

2,032.81

85,378

270,908 270,908

-

567.99

-

-

-

567.99

23,856

23,856

23,856

-

-

-

-

35,981.96

35,981.96

71,964

71,964

71,964

A-285

Cost Estimating Spreadsheet Report
Prefabricated Alt. CS 1

Page 4

Spreadsheet Level

Takeoff Quantity

011-5522--1133.2.200OOfffifcieceAnAdnSdtoSrtaogreagSepaScepace

Office Trailer, furnished,

12.00 ea

rent per month, 32' x 8',

excl. hookups

Storage Boxes, rent per

24.00 ea

month, 20' x 8'

Office And Storage Space

011-5522--1133.4.400FFieiledldOOffifcfieceExEpxepnseense Field Office Expense, office equipment rental, average Field Office Expense, office supplies, average Field Office Expense, telephone bill; avg. bill/month, incl. long dist. Field Office Expense, field office lights & HVAC Field Office Expense Field Offices And Sheds

12.00 mo 12.00 mo 12.00 mo
12.00 mo

011-5566--2266.0.000TTemempoproarayrFyeFnecinncging 011-5566--2266.5.500TTemempoproarayrFyeFnecinncging Temporary Fencing, chain link, 6' high, 11 ga Temporary Fencing Temporary Fencing

2,000.00 lf

011-5588--0000.0.000PProrjoejcetcItdIednetinfitcifaictiaotnion 011-5588--1133.5.500SSigingsns Project Signs Signs Project Identification

50.00 sf

011-7711--2233.0.000FFieiledldEEngnigneineerienrging 011-7711--2233.1.133CConosntsrutrcuticotnioLnaLyaouytout Survey Crew Construction Layout Field Engineering * unassigned *
General Conditions General Conditions

30.00 day

Labor Cost/Unit

Material Cost/Unit

Sub Cost/Unit

Equip Cost/Unit

Other Cost/Unit Total Cost/Unit

Total Amount

-

288.18

-

-

-

288.18

3,458

-

87.89

-

179.37

-

113.60

-

251.11

-

-

-

87.89

2,109

5,568

-

-

-

179.37

2,152

-

-

-

113.60

1,363

-

-

-

251.11

3,013

-

131.53

-

-

-

131.53

1,578

8,107 13,675

3.17

8.37

-

-

-

11.54

23,077
23,077 23,077

-

21.40

-

-

-

21.40

1,070

1,070

1,070

1,898.46

-

-

90.63

-

1,989.09

59,673 59,673 59,673 464,223
464,223

A-286

Cost Estimating Spreadsheet Report
Prefabricated Alt. CS 1

Page 5

Spreadsheet Level

Takeoff Quantity

PePrmermanaennent tWWaalllss Permmaanneennt Wt Walalslls
4000--22--1100CCoonncrcerteeteClCaslassIsI II 030-33-03-00-00.0.000CCaasst-In-PlaceeCCoonnccreretete 030-33-300-5-533.4.400 CCooncreetteeIInnPPlalaccee Approach Slab Concrete In Place Cast-In-Place Concrete 400-2-10 Concrete Class II

84.40 cy

4155--11--99RReeininfoforcricnigngStSeetleel

033-2211--0055.0.000RReienifnofrocrincginSgteSetleAecl cAecsscoersiessories

033-2211--1100.6.600RReienifnofrocrincginIgnIPnlaPclaece

Reinforcing Steel Approach

21,112.00 lb

Slabs

Reinforcing In Place

Reinforcing Steel

Accessories

415-1-9 Reinforcing Steel

** uunassssigignneded* * 033-3377--1133.0.000ShSohtocrtcetreete 033-3377--1133.6.600SShohtocrtcetreet(eW(eWt-Meti-xM) ix) Shotcrete Shotcrete (Wet-Mix) Shotcrete

5,456.00 sf

311-3322--3366.0.000SoSiol iNl aNialiinligng 311-3322--3366.1.166GGroroutuetdedSoSiloNilaNilainilging Gouted soil nailing,drill hole,install # 8 nail,grout,diffclt,grade 75,20 min setup per hole&80'/hr drilling Grouted Soil Nailing Soil Nailing * unassigned *
Permanent Walls Permanent Walls

220.00 ea

SSuubbsstrtuructcutruer-eE-nEdnSdubSsutrbuscttruurce-tEunred-BEenndtsBents
40400-04--45-5CCononccrreettee CCllaasssIIVV ((SSuubbstsrtuructcutruer)e) 030-33-03-00-00.0.000CCaasst-In-PlaceeCCoonnccreretete

Labor Cost/Unit

Material Cost/Unit

Sub Cost/Unit

Equip Cost/Unit

Other Cost/Unit Total Cost/Unit

Total Amount

142.64

173.39

0.37

0.06

26.04

3.68

255.14

639.74

-

20.87

-

0.08

-

14.76

-

243.13

-

336.90

28,434 28,434 28,434 28,434

-

0.51

10,676
10,676 10,676
10,676

-

44.49

-

1,138.01

242,711 242,711 242,711
250,361

250,361 250,361 493,072
532,182

A-287

Cost Estimating Spreadsheet Report
Prefabricated Alt. CS 1

Page 6

Spreadsheet Level

Takeoff Quantity

033-3300--5533.4.400CConocnrcertetIen IPnlaPcleace Concrete Class IV Concrete In Place Cast-In-Place Concrete 400-4-5 Concrete Class IV (Substructure)

78.20 cy

4155--11--55RReeininfoforcricnigngStSeetleSeul bSsutrbuscttruurceture

033-2211--0055.0.000RReienifnofrocrincginSgteSetleAecl cAecsscoersiessories

033-2211--1100.6.600RReienifnofrocrincginIgnIPnlaPclaece

Reinforcing Steel

10,550.00 lb

Reinforcing In Place

Reinforcing Steel

Accessories

415-1-5 Reinforcing Steel

Substructure

4555--113333--22SShheeeteptipleilWe Walla(lTl e(Tmepmorpaorrya)ry) 311-4411--1166.0.000ShSeheet ePtilPinilging 311-4411--1166.1.100SSheheet ePtilPinilginSgysSteymstse ms Sheet piling, steel, Temporary Sheet Piling Systems Sheet Piling 455-133-2 Sheetpile Wall (Temporary)

3,680.00 sf

4555--114433--33TTeestsPt iPleilses

311-6622--0000.0.000DDrirvivenenPiPleilses

311-6622--1133.2.233PPrersetsretrsessedseCdonCcornetcerePtielesPiles

Prestressed Concrete

380.00 vlf

Piles, Test Piles

Prestressed Concrete

Piles

Driven Piles

455-143-3 Test Piles

4555--3344--33CCoonncrcerteetePiPlinilginPgrePsrteresstsreedssed

311-6622--0000.0.000DDrirvivenenPiPleilses

311-6622--1133.2.233PPrersetsretrsessedseCdonCcornetcerePtielesPiles

Prestressed Concrete Piles

640.00 vlf

Prestressed Concrete

Piles

Labor Cost/Unit

Material Cost/Unit

Sub Cost/Unit

Equip Cost/Unit

Other Cost/Unit Total Cost/Unit

Total Amount

285.29

197.30

-

41.73

-

524.32

41,002 41,002 41,002 41,002

0.49

0.50

-

0.11

-

1.09

11,508 11,508 11,508
11,508

4.83

14.29

-

4.33

-

23.45

86,293
86,293 86,293 86,293

29.69

37.67

10.80

37.67

-

18.54

-

6.74

-

85.90

32,641
32,641
32,641 32,641

-

55.21

35,331 35,331

A-288

Cost Estimating Spreadsheet Report
Prefabricated Alt. CS 1

Page 7

Spreadsheet Level

Takeoff Quantity

Driven Piles 455-34-3 Concrete Piling Prestressed

Substructure-End

Substructure-End

Bents

SubSsutbrsutrcutcutruer-eP-Pieierrss Suubbsstrtuructcutruer-Pe-iePrisers

40400-40-42-525CCononccreretete CCllaassss VV SSuuppeersrtsrturcutcutruere

030-33-03-00-00.0.000CCaasst-In-PlaceeCCoonnccreretete

030-33-030-5-533.4.400 CCooncreeteeIInnPPlalaccee

Concrete Class V

94.60 cy

Concrete In Place

Cast-In-Place Concrete 400-4-25 Concrete Class

V Superstructure

40400-04--45-5CCononccrreettee CCllaasssIIVV ((SSuubbstsrtuructcutruer)e) 030-33-03-00-00.0.000CCaasst-In-PlaceeCCoonnccreretete 030-33-300-5-533.4.400 CCooncreetteeIInnPPlalaccee Concrete Class IV Concrete In Place Cast-In-Place Concrete 400-4-5 Concrete Class IV (Substructure)

39.20 cy

4155--11--55RReeininfoforcricnigngStSeetleSeul bSsutrbuscttruurceture

033-2211--0055.0.000RReienifnofrocrincginSgteSetleAecl cAecsscoersiessories

033-2211--1100.6.600RReienifnofrocrincginIgnIPnlaPclaece

Reinforcing Steel

20,042.00 lb

Reinforcing In Place

Reinforcing Steel

Accessories

415-1-5 Reinforcing Steel

Substructure

4555--114433--55TTeestsPt iPleilses

311-6622--0000.0.000DDrirvivenenPiPleilses

311-6622--1133.2.233PPrersetsretrsessedseCdonCcornetcerePtielesPiles

Prestressed concrete piles,

210.00 vlf

24" square, Test Pile

Prestressed Concrete

Piles

Labor Cost/Unit

Material Cost/Unit

Sub Cost/Unit

Equip Cost/Unit

Other Cost/Unit Total Cost/Unit

Total Amount
35,331 35,331

206,775

228.23

179.37

-

33.38

-

440.98

41,717 41,717 41,717 41,717

285.29

197.30

-

41.73

-

524.32

20,553 20,553 20,553 20,553

0.49

0.50

-

0.11

-

1.09

21,861 21,861 21,861
21,861

29.69

65.77

-

18.54

-

114.00

23,940 23,940

A-289

Cost Estimating Spreadsheet Report
Prefabricated Alt. CS 1

Page 8

Spreadsheet Level
Driven Piles 455-143-5 Test Piles

Takeoff Quantity

4555--3344--55CCoonncrcerteetePiPlinilginPgrePsrteresstsreedssed

311-6622--0000.0.000DDrirvivenenPiPleilses

311-6622--1133.2.233PPrersetsretrsessedseCdonCcornetcerePtielesPiles

Prestressed concrete piles,

1,800.00 vlf

24" square,

Prestressed Concrete

Piles

Driven Piles

455-34-5 Concrete Piling

Prestressed

Substructure-Piers

Substructure-Piers

SSuuppeerrsstrturcutcutruerSeuSpeurpsterrusctruurecture
11101-03-3SStrturucctuturreeRReemmovvaallooffEExxisistitning g 020-24-411-1-166..0000 SStruccttuurreeDDeemmooliltiitoionn 022-4411--1166.3.333BBrirdidgegeDDemeomliotiloitnion Bridge demolition Bridge Demolition Structure Demolition 110-3 Structure Removal of Existing

21,048.00 sf

40400-10-41747CComomppoossiittee NeoopprreenneePPadasds 050-50-055-2-233.0.000 MMeetal Fasstteennininggss 055-0055--2233.8.800VVibirbartaiotinon&&BBeaerainrigngPaPdasds Bearing Pads Vibration & Bearing Pads Metal Fastenings 400-147 Composite Neoprene Pads

10.60 cf

4000--22--44CCoonncrcerteeteClCalsassIsI II 030-33-03-00-00.0.000CCaasst-In-PlaceeCCoonnccreretete 030-33-300-5-533.4.400 CCooncreetteeIInnPPlalaccee Concrete Class II Concrete In Place Cast-In-Place Concrete

866.20 cy

Labor Cost/Unit

Material Cost/Unit

Sub Cost/Unit

Equip Cost/Unit

Other Cost/Unit Total Cost/Unit

Total Amount
23,940 23,940

10.80

65.77

-

6.74

-

83.31

149,951

149,951

149,951 149,951

258,022

12.72

-

-

8.26

-

20.98

441,610

441,610

441,610

441,610

78.49

717.46

-

-

-

795.95

8,437

8,437

8,437

8,437

142.65

173.39

-

20.87

-

336.90

291,820 291,820 291,820

A-290

Cost Estimating Spreadsheet Report
Prefabricated Alt. CS 1

Page 9

Spreadsheet Level

Takeoff Quantity

400-2-4 Concrete Class II

40400-50-52-525CCononccrreetteeCCllaassssVVSSuupperesrtsrturcutcutruere

030-33-03-00-00.0.000CCaasst-In-PlaceeCCoonnccreretete

030-33-300-5-533.4.400 CCooncreetteeIInnPPlalaccee

Concrete Class V

162.60 cy

Concrete In Place

Cast-In-Place Concrete

400-5-25 Concrete Class

V Superstructure

4000--99BBrriiddggeeFFlolooroGr Groroovoinvging

322-1133--1133.0.000CConocnrcertetPeaPvianvging

322-1133--1133.2.233CConocnrcertetPeaPvianvginSgurSfaucrefaTcreeaTtmreeanttment

Concrete Grooving

3,536.00 sy

Concrete Paving Surface

Treatment

Concrete Paving

400-9 Bridge Floor

Grooving

4155--11--44RReeininfoforcricnigngStSeetleel

033-2211--0055.0.000RReienifnofrocrincginSgteSetleAecl cAecsscoersiessories

033-2211--1100.6.600RReienifnofrocrincginIgnIPnlaPclaece

Reinforcing Steel

201,944.00 lb

Superstructure

Reinforcing In Place Reinforcing Steel

Accessories

415-1-4 Reinforcing Steel

45485-81--11-212BBrirdidggeeDDeecck ExppaannssioionnJoJionitnt 322-3344--0000.0.000FFabarbirciactaetdedBrBidrgidegses 3232-3-344-1-100..1100 BBrriiddgess,,HHiigghhwwaayy Bridge Deck Expansion Joint Bridges, Highway Fabricated Bridges 458-1-12 Bridge Deck Expansion Joint

274.00 lf

4600--22--11SStrtruucctuturarlaSl tSeteelel 055-1122--2233.0.000StSrutrcutcutruarlaSltSeetleFeol rFoBrriBdgriedsges

Labor Cost/Unit

Material Cost/Unit

Sub Cost/Unit

Equip Cost/Unit

Other Cost/Unit Total Cost/Unit

Total Amount 291,820

228.23

179.37

-

33.38

-

440.98

71,703 71,703 71,703 71,703

2.31

-

-

5.20

-

7.52

26,581

26,581

26,581 26,581

0.37

0.06

105.39

326.45

-

0.08

-

3.69

-

0.51

102,118

102,118 102,118

102,118

-

435.53

119,335
119,335 119,335 119,335

A-291

Cost Estimating Spreadsheet Report
Prefabricated Alt. CS 1

Page 10

Spreadsheet Level

Takeoff Quantity

055-1122--2233.7.777SStrturcutcutruarlaSltSeetlePelroPjeroctjsects Structural Steel Structural Steel Projects Structural Steel For Bridges 460-2-1 Structural Steel

450.00 ton

46416-1-1131-37-7MMulutiltRi RootatatitoionnaallBBeearinggAAssssememblbyly

055-0055--2233.0.000MMeteatlaFl aFsatesnteinngins gs

050-50-055-2-233.8.800 VViibbrraatiioon & Beeaarriingg PPaaddss

Multirotational Bearing

2.00 ea

(1750 Kip)

Vibration & Bearing Pads

Metal Fastenings

461-113-7 Multi Rotational

Bearing Assembly

46416-1-1141-45-5MMulutiltRi RootatatitoionnaallBBeearinggAAssssememblbyly

055-0055--2233.0.000MMeteatlaFl aFsatesnteinngins gs

050-50-055-2-233.8.800 VViibbrraatiioon & Beeaarriingg PPaaddss

Multirotational Bearing

2.00 ea

(1200 Kip)

Vibration & Bearing Pads

Metal Fastenings

461-114-5 Multi Rotational

Bearing Assembly

46426-2-21-111PPoossttTTeennssioonniinnggTTeennddonosns 030-32-32-30-00.0.000SSttrreessssiinngg TTeennddoonsns 033-2233--0055.5.500PPrersetsretrsessinsginSgteSelteel Post Tensioning Strands Prestressing Steel Stressing Tendons 462-2-11 Post Tensioning Tendons

11,364.00 lb

525121-5-5-1-1CCoonnccretee TTrraafffficcRRaailiilningg 3344-7-711--1133..0000 VeehhiicclleeBBaarrriieerrss 344-7711--1133.2.266VVeheihcliceleGuGidueidReaRilsails Concrete Traffic Railing Barrier Bridge Vehicle Guide Rails

1,240.00 lf

Labor Cost/Unit

Material Cost/Unit

Sub Cost/Unit

Equip Cost/Unit

Other Cost/Unit Total Cost/Unit

Total Amount

1,271.58

1,913.23

-

515.29

-

3,700.10

1,665,046 1,665,046 1,665,046
1,665,046

594.61

9,566.17

-

-

-

10,160.78

20,322

20,322 20,322 20,322

392.44

5,978.86

-

-

-

6,371.30

12,743

12,743 12,743 12,743

1.90

0.61

-

0.02

-

2.53

28,728 28,728 28,728 28,728

12.88

49.03

-

4.44

-

66.35

82,275 82,275

A-292

Cost Estimating Spreadsheet Report
Prefabricated Alt. CS 1

Page 11

Spreadsheet Level
Vehicle Barriers 521-5-1 Concrete Traffic Railing
Superstructure Superstructure

Takeoff Quantity

Labor Cost/Unit

Material Cost/Unit

Sub Cost/Unit

Equip Cost/Unit

Other Cost/Unit Total Cost/Unit

TotalAmount 82,275 82,275
2,870,718

A-293

Cost Estimating Spreadsheet Report
Prefabricated Alt. CS 1

Description Labor
Material Subcontract
Equipment Other
Total

Amount Net Amount 1,889,726 1,889,726 1,887,855 1,887,855

789,209

789,209

679,331

679,331

94,564

94,564

5,340,685

Estimate Totals

Totals

Hours 10,449.281 ch

Rate

5,340,685 5,340,685

3,261.644 ch

Page 12

Cost Basis

Percent of Total 35.38% 35.35% 14.78% 12.72% 1.77%
100.00

100.00%

A-294

Cost Estimating Spreadsheet Report
Conventional Alt. CS 1
Every Day Counts - Case Study 1

Project name
Labor rate table Equipment rate table
Notes

Conventional Alt. CS 1 Fla.
Labor 2011
Equip 2011
1. Pricing is 2011 $. 2. Construction Schedule of 28 mos. 3. Rates reflect majority of work performed evenings to minimize disruption. 4. 2 Bridges. 5. Labor Cost/Unit - This reflects the cost of Labor to put one unit of measure of work in place. This is comprised of a typical crew with associated productivity required to perform the activity. Labor is priced up to include base rate, fringes, taxes, insurance, etc. 6. Material Cost/Unit - This cost represents the final installed cost for all the materials associated with the item of work. 7. Sub Contract Cost/Unit - this represents the Sub Contract all in Cost to put one unit of work in place. This cost includes all costs necessary to reflect a total installed cost (incls. Labor, equipment and material). 8. Equipment Cost/Unit - This represents the cost of Construction Equipment necessary to put one unit of work in place. This cost includes equipment ownership and maintenance and operational costs. 9. Other Cost/Unit - This cost represents all other costs necessary to perform the item of work and not covered by the abovementioned costs. 10. Total cost/unit - This is the summation of all unit costs to arrive at a total cost per unit to put one item of work in place. 11. Total Amount - Total cost to put the quantity of units specified in place.

Page 1

A-295

Cost Estimating Spreadsheet Report
Conventional Alt. CS 1

Page 2

Spreadsheet Level

Takeoff Quantity

AdAdidtdioitnioanlaCl CososttAAddditioonnaallCCoostsDt eDtoeutor ur

** unassssigignneded* *

011-5544--3366.0.000EEquqiupimpmenet nMt oMboilbizialitziaontion

010-15-544-3-366.5.500 MMoobilliizzation OOrr Deemmoobb. .

Transport Bridge to Site

4.00 ea

Transport Bridge back to

4.00 ea

FDOT

Mobilization Or Demob.

Equipment Mobilization

010-15-55-50-00.00.00VVeehhiiccuullaarr AAccceessssAAnnddPaPrakriknigng

010-15-55-52-32.35.500RRooaaddss AnnddSSidideewwalaklsks

Temporary, roads

2,000.00 lf

Temporary, roads Remove

2,000.00 lf

Roads And Sidewalks

Vehicular Access And

Parking

322-3344--0000.0.000FFabarbirciactaetdedBrBidrgidegses 322-3344--1100.1.100BBrirdidgegse,sH, iHghigwhawyay Fabricated highway bridges, Install Fabricated highway bridges, Remove Fabricated highway bridges, concrete in place, abutment Fabricated highway bridges, concrete in place, abutment Remove Bridges, Highway Fabricated Bridges

330.00 lf 330.00 lf 350.00 cy
350.00 cy

344-7711--1133.0.000VVeheihcliceleBaBrarirerries rs

344-7711--1133.1.177SSeceucruitryitVyeVheichleicBlearBraierrrsiers

Maintain Detour

500.00 day

Security Vehicle Barriers

Vehicle Barriers

* unassigned *

Additional Cost

Additional Cost

Detour

Labor Cost/Unit

Material Cost/Unit

Sub Cost/Unit

Equip Cost/Unit

Other Cost/Unit Total Cost/Unit

Total Amount

517.79

-

517.79

-

50.64 50.64 293.61

0.00 198.50
0.00

-

-

-

817.10

-

817.11

-

-

1,334.89

-

1,334.90

956.62 119.58

956.62 119.58

5,340 5,340
10,679 10,679
1,913,234 239,154
2,152,389 2,152,389

-

13.97

-

13.97

-

19.01

-

64.61

-

64.61

-

511.12

-

149.47

149.47

21,320 21,322 178,891
52,315
273,848 273,848

-

-

89.68

89.68

44,841

44,841

44,841

2,481,758

2,481,758

A-296

Cost Estimating Spreadsheet Report
Conventional Alt. CS 1

Page 3

Spreadsheet Level

Takeoff Quantity

Geenneerraal lCConodnidtiiotniosnGsenGeernaleCraolnCdiotinondsitions

** unassssigignneded* *

011-3311--0000.0.000PProrjoejcetcMt ManaangaegmeemnteAnntdACnodoCrdoinoardtiionnation

011-3311--1133.2.200FFieieldldPPeresrosnonnenl el

Field Personnel, clerk,

117.00 week

average

Field engineer, average

121.00 week

Field Personnel, project

121.00 week

manager, average

Field Personnel,

117.00 week

superintendent, average

Field Personnel

Project Management And

Coordination

011-3322--3333.0.000PPhohtootgorgarpahpichiDc oDcoumcuemnteatniotantion

011-3322--3333.5.500PPhohtootgorgarpahpshs

Construction Photographs

120.00 set

Photographs

Photographic

Documentation

0011-4-455--0000.00 QQuuaalliittyyCCoonntrtrool l 0011-4-455--2233..550 Teesstitningg Field Testing Testing Quality Control

2.00 prjc

010-15-25-21-31.30.000FFieieldldOOfffiicceess AnnddSShhedesds

011-5522--1133.2.200OOfffifcieceAnAdnSdtoSrtaogreagSepaScepace

Office Trailer, furnished,

28.00 ea

rent per month, 32' x 8',

excl. hookups

Storage Boxes, rent per

56.00 ea

month, 20' x 8'

Office And Storage Space

011-5522--1133.4.400FFieiledldOOffifcfieceExEpxepnseense Field Office Expense, office equipment rental, average Field Office Expense, office supplies, average

28.00 mo 28.00 mo

Labor Cost/Unit

Material Cost/Unit

Sub Cost/Unit

Equip Cost/Unit

Other Cost/Unit Total Cost/Unit

Total Amount

472.96
1,457.74 2,397.18
2,202.81

-

-

-

-

472.96

55,336

-

-

-

-

1,457.74

176,387

-

-

-

-

2,397.18

290,059

-

-

-

-

2,202.81

257,729

779,511 779,511

-

567.99

-

-

-

567.99

68,159

68,159

68,159

-

-

-

-

35,981.96

35,981.96

71,964

71,964

71,964

-

288.18

-

87.89

-

179.37

-

113.60

-

-

-

288.18

8,069

-

-

-

87.89

4,922

12,991

-

-

-

179.37

5,022

-

-

-

113.60

3,181

A-297

Cost Estimating Spreadsheet Report
Conventional Alt. CS 1

Page 4

Spreadsheet Level

Takeoff Quantity

011-5522--1133.4.400FFieiledldOOffifcfieceExEpxepnseense Field Office Expense, telephone bill; avg. bill/month, incl. long dist. Field Office Expense, field office lights & HVAC Field Office Expense Field Offices And Sheds

28.00 mo 28.00 mo

011-5566--2266.0.000TTemempoproarayrFyeFnecinncging 011-5566--2266.5.500TTemempoproarayrFyeFnecinncging Temporary Fencing, chain link, 6' high, 11 ga Temporary Fencing Temporary Fencing

2,000.00 lf

011-5588--0000.0.000PProrjoejcetcItdIednetinfitcifaictiaotnion 011-5588--1133.5.500SSigingsns Project Signs Signs Project Identification

50.00 sf

011-7711--2233.0.000FFieiledldEEngnigneineerienrging 011-7711--2233.1.133CConosntsrutrcuticotnioLnaLyaouytout Survey Crew Construction Layout Field Engineering * unassigned *
General Conditions General Conditions

90.00 day

PePrmermanaennent tWWaalllss Permmaanneennt Wt Walalslls
4000--22--1100CCoonncrcerteeteClCaslassIsI II 030-33-03-00-00.0.000CCaasst-In-PlaceeCCoonnccreretete 030-33-300-5-533.4.400 CCooncreetteeIInnPPlalaccee Approach Slab Concrete In Place Cast-In-Place Concrete 400-2-10 Concrete Class II

262.60 cy

4155--11--99RReeininfoforcricnigngStSeetleel 033-2211--0055.0.000RReienifnofrocrincginSgteSetleAecl cAecsscoersiessories

Labor Cost/Unit

Material Cost/Unit

Sub Cost/Unit

Equip Cost/Unit

Other Cost/Unit Total Cost/Unit

Total Amount

-

251.11

-

-

-

251.11

7,031

-

131.54

-

-

-

131.54

3,683

18,917 31,908

3.43

8.37

-

-

-

11.80

23,607
23,607 23,607

-

21.40

-

-

-

21.40

1,070

1,070

1,070

2,057.22

-

-

90.63

-

2,147.85

193,306

193,306

193,306

1,169,525

1,169,525

154.57

173.39

-

20.87

-

348.83

91,602 91,602 91,602 91,602

A-298

Cost Estimating Spreadsheet Report
Conventional Alt. CS 1

Page 5

Spreadsheet Level

Takeoff Quantity

033-2211--1100.6.600RReienifnofrocrincginIgnIPnlaPclaece Reinforcing Steel Approach Slabs Reinforcing In Place Reinforcing Steel Accessories 415-1-9 Reinforcing Steel

53,832.00 lb

552211-8-8-1-1CCoonncret TTrafficcRRaaiilliinngg 3344-7-711--1133..0000 VeehhiicclleeBBaarrriieerrss 344-7711--1133.2.266VVeheihcliceleGuGidueidReaRilsails Concrete Traffic Railing Barrier Retaining Wall Vehicle Guide Rails Vehicle Barriers 521-8-1 Concret Traffic Railing

100.00 lf

5488--1122RReetataininigigWWalal lSl ySstyesmtem 322-3322--2233.0.000RReteatianinginWg aWllaslls 322-3322--2233.1.133RReteatianinginWg aWllaslls Retaining Wall System Retaining Walls Retaining Walls 548-12 Retainig Wall System
Permanent Walls Permanent Walls

13,826.00 sf

SSuubbsstrtuructcutruer-eE-nEdnSdubSsutrbuscttruurce-tEunred-BEenndtsBents

40400-04--45-5CCononccrreettee CCllaasssIIVV ((SSuubbstsrtuructcutruer)e)

030-33-03-00-00.0.000CCaasst-In-PlaceeCCoonnccreretete

030-33-300-5-533.4.400 CCooncreetteeIInnPPlalaccee

Concrete Class IV

144.00 cy

Concrete In Place

Cast-In-Place Concrete

400-4-5 Concrete Class IV

(Substructure)

4155--11--55RReeininfoforcricnigngStSeetleSeul bSsutrbuscttruurceture 033-2211--0055.0.000RReienifnofrocrincginSgteSetleAecl cAecsscoersiessories 033-2211--1100.6.600RReienifnofrocrincginIgnIPnlaPclaece

Labor Cost/Unit

Material Cost/Unit

Sub Cost/Unit

Equip Cost/Unit

Other Cost/Unit Total Cost/Unit

Total Amount

0.40

0.06

-

0.08

-

0.54

28,866
28,866 28,866
28,866

13.96

49.03

-

4.44

-

67.43

6,743
6,743 6,743 6,743

8.28

14.05

-

4.24

-

26.58

367,434 367,434 367,434 367,434

494,644

309.15

197.30

-

41.73

-

548.18

78,938 78,938 78,938 78,938

A-299

Cost Estimating Spreadsheet Report
Conventional Alt. CS 1

Page 6

Spreadsheet Level

Takeoff Quantity

033-2211--1100.6.600RReienifnofrocrincginIgnIPnlaPclaece Reinforcing Steel Reinforcing In Place Reinforcing Steel Accessories 415-1-5 Reinforcing Steel Substructure

19,440.00 lb

4555--114433--55TTeestsPt iPleilses

311-6622--0000.0.000DDrirvivenenPiPleilses

311-6622--1133.2.233PPrersetsretrsessedseCdonCcornetcerePtielesPiles

Prestressed concrete piles,

380.00 vlf

24" square, Test Pile

Prestressed Concrete

Piles

Driven Piles

455-143-5 Test Piles

4555--3344--55CCoonncrcerteetePiPlinilginPgrePsrteresstsreedssed

311-6622--0000.0.000DDrirvivenenPiPleilses

311-6622--1133.2.233PPrersetsretrsessedseCdonCcornetcerePtielesPiles

Prestressed concrete piles,

2,240.00 vlf

24" square,

Prestressed Concrete Piles Driven Piles 455-34-5 Concrete Piling

Prestressed

Substructure-End

Substructure-End

Bents

SubSsutbrsutrcutcutruer-eP-Pieierrss Suubbsstrtuructcutruer-Pe-iePrisers

40400-04--45-5CCononccrreettee CCllaasssIIVV ((SSuubbstsrtuructcutruer)e)

030-33-03-00-00.0.000CCaasst-In-PlaceeCCoonnccreretete

030-33-300-5-533.4.400 CCooncreetteeIInnPPlalaccee

Concrete Class IV

283.40 cy

Concrete In Place

Cast-In-Place Concrete

400-4-5 Concrete Class IV

(Substructure)

Labor Cost/Unit

Material Cost/Unit

Sub Cost/Unit

Equip Cost/Unit

Other Cost/Unit Total Cost/Unit

Total Amount

0.53

0.50

-

0.11

-

1.13

21,996 21,996 21,996
21,996

32.18

65.77

11.70

65.77

-

18.54

-

6.74

-

116.48

44,263
44,263
44,263 44,263

-

84.21

188,628

188,628

188,628 188,628

333,825

309.15

197.30

-

41.73

-

548.18

155,354 155,354 155,354 155,354

A-300

Cost Estimating Spreadsheet Report
Conventional Alt. CS 1

Page 7

Spreadsheet Level

Takeoff Quantity

4155--11--55RReeininfoforcricnigngStSeetleSeul bSsutrbuscttruurceture

033-2211--0055.0.000RReienifnofrocrincginSgteSetleAecl cAecsscoersiessories

033-2211--1100.6.600RReienifnofrocrincginIgnIPnlaPclaece

Reinforcing Steel

42,510.00 lb

Reinforcing In Place

Reinforcing Steel

Accessories

415-1-5 Reinforcing Steel

Substructure

4555--114433--55TTeestsPt iPleilses

311-6622--0000.0.000DDrirvivenenPiPleilses

311-6622--1133.2.233PPrersetsretrsessedseCdonCcornetcerePtielesPiles

Prestressed concrete piles,

170.00 vlf

24" square, Test Pile

Prestressed Concrete

Piles

Driven Piles

455-143-5 Test Piles

4555--3344--55CCoonncrcerteetePiPlinilginPgrePsrteresstsreedssed

311-6622--0000.0.000DDrirvivenenPiPleilses

311-6622--1133.2.233PPrersetsretrsessedseCdonCcornetcerePtielesPiles

Prestressed concrete piles,

1,960.00 vlf

24" square,

Prestressed Concrete

Piles

Driven Piles

455-34-5 Concrete Piling

Prestressed

Substructure-Piers

Substructure-Piers

SSuuppeerrsstrturcutcutruerSeuSpeurpsterrusctruurecture
11101-03-3SStrturucctuturreeRReemmovvaallooffEExxisistitning g 020-24-411-1-166..0000 SStruccttuurreeDDeemmooliltiitoionn 022-4411--1166.3.333BBrirdidgegeDDemeomliotiloitnion Bridge demolition Bridge Demolition Structure Demolition

21,048.00 sf

Labor Cost/Unit

Material Cost/Unit

Sub Cost/Unit

Equip Cost/Unit

Other Cost/Unit Total Cost/Unit

Total Amount

0.53

0.50

-

0.11

-

1.13

48,100 48,100 48,100
48,100

32.18

65.77

11.70

65.77

-

18.54

-

6.74

-

116.48

19,802
19,802
19,802 19,802

-

84.21

165,050

165,050

165,050 165,050

388,305

15.31

-

-

9.18

-

24.49

515,552

515,552

515,552

A-301

Cost Estimating Spreadsheet Report
Conventional Alt. CS 1

Page 8

Spreadsheet Level

Takeoff Quantity

110-3 Structure Removal of Existing

40400-10-41747CComomppoossiittee NeoopprreenneePPadasds 050-50-055-2-233.0.000 MMeetal Fasstteennininggss 055-0055--2233.8.800VVibirbartaiotinon&&BBeaerainrigngPaPdasds Bearing Pads Vibration & Bearing Pads Metal Fastenings 400-147 Composite Neoprene Pads

37.80 cf

4000--22--44CCoonncrcerteeteClCalsassIsI II 030-33-03-00-00.0.000CCaasst-In-PlaceeCCoonnccreretete 030-33-300-5-533.4.400 CCooncreetteeIInnPPlalaccee Concrete Class II Concrete In Place Cast-In-Place Concrete 400-2-4 Concrete Class II

905.20 cy

4000--99BBrriiddggeeFFlolooroGr Groroovoinvging

322-1133--1133.0.000CConocnrcertetPeaPvianvging

322-1133--1133.2.233CConocnrcertetPeaPvianvginSgurSfaucrefaTcreeaTtmreeanttment

Concrete grooving

4,158.00 sy

Concrete Paving Surface

Treatment

Concrete Paving

400-9 Bridge Floor

Grooving

4155--11--44RReeininfoforcricnigngStSeetleel

033-2211--0055.0.000RReienifnofrocrincginSgteSetleAecl cAecsscoersiessories

033-2211--1100.6.600RReienifnofrocrincginIgnIPnlaPclaece

Reinforcing Steel

185,566.00 lb

Superstructure

Reinforcing In Place Reinforcing Steel

Accessories

415-1-4 Reinforcing Steel

4500--22--5544PPrreestsrtersessedseBdeaBmesams 322-3344--0000.0.000FFabarbirciactaetdedBrBidrgidegses 322-3344--1100.1.100BBrirdidgegse,sH, iHghigwhawyay

Labor Cost/Unit

Material Cost/Unit

Sub Cost/Unit

Equip Cost/Unit

Other Cost/Unit Total Cost/Unit

Total Amount 515,552

85.05

717.46

-

-

-

802.51

30,335

30,335

30,335

30,335

154.57

173.39

2.51

-

-

20.87

-

5.20

-

348.83

315,757 315,757 315,757 315,757

-

7.71

32,061 32,061
32,061 32,061

0.40

0.06

-

0.08

-

0.54

99,503
99,503 99,503
99,503

A-302

Cost Estimating Spreadsheet Report
Conventional Alt. CS 1

Page 9

Spreadsheet Level
322-3344--1100.1.100BBrirdidgegse,sH, iHghigwhawyay Fabricated highway bridges, precast, prestressed concrete, I beams Bridges, Highway Fabricated Bridges 450-2-54 Prestressed Beams

Takeoff Quantity 4,224.00 lf

45485-81--11-212BBrirdidggeeDDeecck ExppaannssioionnJoJionitnt 322-3344--0000.0.000FFabarbirciactaetdedBrBidrgidegses 3232-3-344-1-100..1100 BBrriiddggess,,HHiigghhwwaayy Bridge Deck Expansion Joint Bridges, Highway Fabricated Bridges 458-1-12 Bridge Deck Expansion Joint

274.00 lf

525121-5-5-1-1CCoonnccretee TTrraafffficcRRaailiilningg 3344-7-711--1133..0000 VeehhiicclleeBBaarrriieerrss 344-7711--1133.2.266VVeheihcliceleGuGidueidReaRilsails Concrete Traffic Railing Barrier Bridge Vehicle Guide Rails Vehicle Barriers 521-5-1 Concrete Traffic
Railing Superstructure
Superstructure

1,296.00 lf

Labor Cost/Unit

Material Cost/Unit

Sub Cost/Unit

Equip Cost/Unit

Other Cost/Unit Total Cost/Unit

Total Amount

-

-

-

-

191.32

191.32

808,150

808,150 808,150 808,150

114.21

326.45

-

3.69

-

444.34

121,750
121,750 121,750 121,750

13.96

49.03

-

4.44

-

67.43

87,387

87,387 87,387 87,387

2,010,495

A-303

Cost Estimating Spreadsheet Report
Conventional Alt. CS 1

Description Labor
Material Subcontract
Equipment Other
Total

Amount Cuts/Adds
2,119,985 1,210,878

Net Amount
2,119,985 1,210,878

418,030 3,129,659 6,878,552

418,030 3,129,659

Estimate Totals

Totals

Hours 21,670.339 ch

Rate

6,878,552 6,878,552

2,561.883 ch

Page 10

Cost Basis

Percent of Total
30.82% 17.60%

6.08% 45.50% 100.00

100.00%

A-304

DATE : 11/15/2013 PAGE : 1

New Jersey Department of Transportation

JOB ESTIMATE REPORT ====================================================================================================================================

JOB NUMBER : 960694

SPEC YEAR: 07

DESCRIPTION: N.J. ROUTE 10 OVER PASSAIC RIVER SUPERSTRUCTURE REPLACEMENT

ITEMS FOR JOB 960694

LINE ITEM

ALT UNITS DESCRIPTION

QUANTITY

PRICE

AMOUNT

----------------------------------------------------------------------------------------------------------------------------------

0001 151006M

DOLL PERFORMANCE BOND AND PAYMENT BOND

1.000

27000.00

27000.00

0002 152004P

DOLL OWNER'S AND CONTRACTOR'S PROTECTIVE

1.000

10000.00

10000.00

LIAB

0003 152015P

DOLL POLLUTION LIABILITY INSURANCE

1.000

10000.00

10000.00

0004 153003P

LS

PROGRESS SCHEDULE

1.000

10000.00

10000.00

0005 153006P

U

PROGRESS SCHEDULE UPDATE

2.000

500.00

1000.00

0006 153012P

HOUR TRAINEES

300.000

1.00

300.00

0007 154003P

LS

MOBILIZATION

1.000

380000.00

380000.00

0008 155009M

U

FIELD OFFICE TYPE C SET UP

1.000

25000.00

25000.00

0009 155027M

MO

FIELD OFFICE TYPE C MAINTENANCE

10.000

3400.00

34000.00

0010 157004M

DOLL CONSTRUCTION LAYOUT

1.000

45000.00

45000.00

0011 158009M

LF

HEAVY DUTY SILT FENCE, ORANGE

1944.000

7.00

13608.00

0012 158030M

U

INLET FILTER TYPE 2, 2' X 4'

27.000

124.00

3348.00

0013 158033M

U

INLET FILTER TYPE 2, 4' X 4'

8.000

165.00

1320.00

0014 158045M

LF

FLOATING TURBIDITY BARRIER, TYPE 2

312.000

20.00

6240.00

0015 158055M

U

SEDIMENT CONTROL BAG

1.000

700.00

700.00

0016 158063P

LS

CONCRETE WASHOUT SYSTEM

1.000

1000.00

1000.00

0017 158072M

U

OIL ONLY EMERGENCY SPILL KIT, TYPE 1

2.000

800.00

1600.00

0018 159003M

U

BREAKAWAY BARRICADE

20.000

65.00

1300.00

0019 159006M

U

DRUM

140.000

45.00

6300.00

0020 159009M

U

TRAFFIC CONE

100.000

12.00

1200.00

0021 159012M

SF

CONSTRUCTION SIGNS

1750.000

11.00

19250.00

0022 159015M

U

CONSTRUCTION IDENTIFICATION SIGN, 4' X

2.000

1200.00

2400.00

8

0023 159021P

LF

CONSTRUCTION BARRIER CURB

1500.000

50.00

75000.00

0024 159027M

U

FLASHING ARROW BOARD, 4' X 8'

2.000

2500.00

5000.00

0025 159030M

U

PORTABLE VARIABLE MESSAGE SIGN

8.000

10000.00

80000.00

0026 159051M

U

TEMPORARY CRASH CUSHION, INERTIAL

1.000

11000.00

11000.00

BARRIE

0027 159108M

U

TRAFFIC CONTROL TRUCK WITH MOUNTED

2.000

12500.00

25000.00

CRASH

0028 159114M

LF

REMOVABLE BLACK LINE MASKING TAPE, 6"

16000.000

2.00

32000.00

0029 0030 0031 0032 0033 0034 0035 0036 0037 0038 0039

159120M 159126M 159132M 159141M 160004M 160007M 161003P 201003P 202006M 202009P 202021P

LF LF SF HOUR DOLL DOLL LS LS CY CY SY

TEMPORARY PAVEMENT MARKING TAPE, 4" TEMPORARY TRAFFIC STRIPES, 4" TEMPORARY PAVEMENT MARKINGS TRAFFIC DIRECTOR, FLAGGER FUEL PRICE ADJUSTMENT ASPHALT PRICE ADJUSTMENT FINAL CLEANUP CLEARING SITE EXCAVATION, TEST PIT EXCAVATION, UNCLASSIFIED REMOVAL OF PAVEMENT

900.000 36000.000
650.000 120.000
1.000 1.000 1.000 1.000 10.000 755.000 1156.000

1.00 0.25 3.00 95.00 1400.00 5700.00 7500.00 40000.00 265.00 30.00 28.00

900.00 9000.00 1950.00 11400.00 1400.00 5700.00 7500.00 40000.00 2650.00 22650.00 32368.00

A-305

DATE : 11/15/2013 PAGE : 2

New Jersey Department of Transportation

JOB ESTIMATE REPORT

====================================================================================================================================

0040 203054M

CY

FLOWABLE CONCRETE FILL

5.000

28.00

140.00

0041 301006P

CY

SUBBASE

337.000

40.00

13480.00

0042 302036P

SY

DENSE-GRADED AGGREGATE BASE COURSE, 6"

1160.000

13.00

15080.00

T

0043 304006P

SY

CONCRETE BASE COURSE, 9" THICK

97.000

108.00

10476.00

0044 401009P

SY

HMA MILLING, 3" OR LESS

18927.000

3.00

56781.00

0045 401021M

SY

HOT MIX ASPHALT PAVEMENT REPAIR

100.000

38.00

3800.00

0046 401027M

LF

POLYMERIZED JOINT ADHESIVE

16500.000

0.25

4125.00

0047 401030M

GAL

TACK COAT

2049.000

1.50

3073.50

0048 401036M

GAL

PRIME COAT

373.000

2.50

932.50

0049 401048M

T

HOT MIX ASPHALT 9.5 M 76 SURFACE COURSE

1200.000

110.00

132000.00

0050 401060M

0051 401078M

0052 401099M 0053 401108M 0054 453006M

0055 0056 0057 0058 0059 0060 0061 0062 0063

501009P 601122P 601249P 601404P 602012M 602099M 602210M 602213M 602290M

0064 603103P

T

HOT MIX ASPHALT 12.5 M 76 SURFACE

COURSE

T

HOT MIX ASPHALT 12.5 M 76 INTERMEDIATE

C

T

HOT MIX ASPHALT 25 M 64 BASE COURSE

U

CORE SAMPLES, HOT MIX ASPHALT

SY

FULL DEPTH CONCRETE PAVEMENT REPAIR,

HMA

LS

TEMPORARY COFFERDAM

LF

15" REINFORCED CONCRETE PIPE

LF

6" HIGH DENSITY POLYETHYLENE PIPE

LF

SUBBASE OUTLET DRAIN

U

INLET, TYPE B

U

RESET EXISTING CASTING

U

BICYCLE SAFE GRATE

U

CURB PIECE

U

INLET, NON-STANDARD SEE CONSTRUCTION

DETAILS

CY

RIPRAP STONE SCOUR PROTECTION (D50=12")

1197.000
188.000
437.000 5.000
420.000
1.000 102.000
45.000 106.000
7.000 37.000
2.000 11.000
3.000
22.000

100.00
95.00
135.00 150.00 220.00
5000.00 74.00 40.00 40.00
2750.00 490.00 430.00 360.00
5100.00
115.00

119700.00
17860.00
58995.00 750.00
92400.00
5000.00 7548.00 1800.00 4240.00 19250.00 18130.00
860.00 3960.00 15300.00
2530.00

0065 605209P 0066 605212P 0067 606024P

LF

ORNAMENTAL FENCE

LF

RESET FENCE

SY

CONCRETE SIDEWALK, REINFORCED, 6" THICK

95.000 85.000 50.000

55.00 35.00 65.00

5225.00 2975.00 3250.00

0068 0069 0070 0071 0072 0073

606039P 606075P 606084P 607018P 607030P 607039P

0074 607076P 0075 608003P

SY

HOT MIX ASPHALT DRIVEWAY, 6" THICK

SY

CONCRETE ISLAND, 4" THICK

SY

DETECTABLE WARNING SURFACE

LF

9" X 16" CONCRETE VERTICAL CURB

LF

12" X 13" CONCRETE SLOPING CURB

LF

24" X 35" CONCRETE BARRIER CURB,

DOWELLE

LF

BELGIAN BLOCK CURB

SY

NONVEGETATIVE SURFACE, HOT MIX ASPHALT

106.000 24.000 4.000
767.000 112.000 1279.000
420.000 233.000

58.00 105.00 290.00
25.00 25.00 450.00
35.00 26.00

6148.00 2520.00 1160.00 19175.00 2800.00 575550.00
14700.00 6058.00

0076 0077 0078 0079 0080 0081 0082 0083

609003M 609024M 609039M 609075M 610003M 610006M 610009M 610012M

LF

BEAM GUIDE RAIL

U

FLARED GUIDE RAIL TERMINAL

U

BEAM GUIDE RAIL ANCHORAGE

LF

REMOVAL OF BEAM GUIDE RAIL

LF

TRAFFIC STRIPES, 4"

LF

TRAFFIC STRIPES, 6"

SF

TRAFFIC MARKINGS

U

RPM, MONO-DIRECTIONAL, WHITE LENS

232.000 2.000 3.000
268.000 16785.000
1070.000 932.000 72.000

15.00 2000.00
750.00 2.00 0.30 0.70 9.00
27.00

3480.00 4000.00 2250.00
536.00 5035.50
749.00 8388.00 1944.00

A-306

DATE : 11/15/2013 PAGE : 3

New Jersey Department of Transportation

JOB ESTIMATE REPORT

====================================================================================================================================

0084 610018M

U

RPM, MONO-DIRECTIONAL, AMBER LENS

72.000

27.00

1944.00

0085 610024M

U

REMOVAL OF RPM

144.000

22.00

3168.00

0086 610036M

LF

REMOVAL OF TRAFFIC STRIPES

11100.000

0.50

5550.00

0087 610039M

SF

REMOVAL OF TRAFFIC MARKINGS

30.000

3.50

105.00

0088 611348M

U

CRASH CUSHION, LOW MAINTENANCE,

2.000

21000.00

42000.00

COMPRESS

0089 612003P

SF

REGULATORY AND WARNING SIGN

70.000

36.00

2520.00

0090 612030P

SF

OVERHEAD STREET NAME SIGNS

6.000

70.00

420.00

0091 651255M

U

RESET WATER VALVE BOX

8.000

200.00

1600.00

0092 654007P

LS

ELECTRICAL UTILITY RELOCATION,

1.000

15000.00

15000.00

_________ JCP&L

0093 702033P

LF

TRAFFIC SIGNAL CABLE, 10 CONDUCTOR

446.000

4.00

1784.00

0094 702036M

U

TRAFFIC SIGNAL HEAD

4.000

2000.00

8000.00

0095 702039M

U

PEDESTRIAN SIGNAL HEAD

2.000

1000.00

2000.00

0096 702042M

U

PUSH BUTTON

2.000

200.00

400.00

0097 702054M

LS

TEMPORARY TRAFFIC SIGNAL SYSTEM,

1.000

60000.00

60000.00

LOCATIO 1

0098 702054M

LS

TEMPORARY TRAFFIC SIGNAL SYSTEM,

1.000

70000.00

70000.00

LOCATIO 2

0099 702054M

LS

TEMPORARY TRAFFIC SIGNAL SYSTEM,

1.000

150000.00

150000.00

LOCATIO 3

0100 702057M

LS

INTERIM TRAFFIC SIGNAL SYSTEM, LOCATION

1.000

11000.00

11000.00

1

0101 804006P

SY

TOPSOILING, 4" THICK

423.000

5.00

2115.00

0102 806006P

SY

FERTILIZING AND SEEDING, TYPE A-3

423.000

5.00

2115.00

0103 809003M

SY

STRAW MULCHING

423.000

4.00

1692.00

0104 809018M

SY

WOOD MULCHING

80.000

6.00

480.00

0105 811069M

U

EVERGREEN SHRUB, 36-42" HIGH, B&B

9.000

90.00

810.00

0106 811075M

U

EVERGREEN SHRUB, 24-30" HIGH, B&B

21.000

80.00

1680.00

0107 201006P

LS

CLEARING SITE, BRIDGE (___) STAGE 1,

1.000

55000.00

55000.00

1402-153

0108 201006P

LS

CLEARING SITE, BRIDGE (___) STAGE 2,

1.000

55000.00

55000.00

1402-153

0109 201039P

LS

TEMPORARY SHIELDING

1.000

56000.00

56000.00

0110 203009P

CY

I-9 SOIL AGGREGATE

20.000

75.00

1500.00

0111 504006P

LB

REINFORCEMENT STEEL, EPOXY-COATED

26030.000

1.50

39045.00

0112 504024P

CY

CONCRETE ABUTMENT WALL

10.000

1200.00

12000.00

0113 504030P

CY

CONCRETE PIER SHAFT

9.000

1000.00

9000.00

0114 504032P

CY

CONCRETE DIAPHRAGM, HPC

49.000

2150.00

105350.00

0115 504036P

SY

EPOXY WATERPROOFING

49.000

50.00

2450.00

0116 505064P

SF

PREFAB PRESTRESS CONC SUPER UNIT

6886.000

65.00

447590.00

0117 506003P

LS

STRUCTURAL STEEL

1.000

3000.00

3000.00

0118 506006P

U

REINFORCED ELASTOMERIC BEARING ASSEMBLY

84.000

2000.00

168000.00

0119 0120 0121 0122 0123 0124

507015P 507023P 507025P 507033P 507039P 507048M

0125 507066P 0126 509003P 0127 520003P

LF

STRIP SEAL EXPANSION JOINT ASSEMBLY

CY

CONCRETE BRIDGE APPROACH, HES

CY

CONCRETE BRIDGE DECK, HES

CY

CONCRETE BRIDGE SIDEWALK, HPC

LF

CONCRETE BRIDGE PARAPET, HPC

LF

24" BY 32" CONCRETE BARRIER CURB,

BRIDGE

SY

PRECAST CONCRETE BRIDGE APPROACH

LF

BRIDGE RAILING (1 RAIL, ALUMINUM)

U

PERMANENT GROUND ANCHOR

114.000 52.000 77.000 42.000
224.000 107.000
296.000 205.000
18.000

300.00 750.00 750.00 600.00 225.00 135.00
600.00 100.00 13200.00

34200.00 39000.00 57750.00 25200.00 50400.00 14445.00
177600.00 20500.00
237600.00

A-307

DATE : 11/15/2013 PAGE : 4

New Jersey Department of Transportation

JOB ESTIMATE REPORT

====================================================================================================================================

0128 520006P

U

GROUND ANCHOR PERFORMANCE LOAD TEST

4.000

1500.00

6000.00

0129 555003M

SF

SUBSTRUCTURE CONCRETE REPAIR

115.000

240.00

27600.00

0130 701021P

LF

3" RIGID METALLIC CONDUIT

560.000

35.00

19600.00

----------------------------------------------------------------------------------------------------------------------------------

ITEM TOTAL

4286451.50

INFLATED ITEM TOTAL

4286451.50

TOTALS FOR JOB 960694

----------------------------------------------------------------------------------------------------------------------------------

ESTIMATED COST:

4286451.50

CONTINGENCY PERCENT ( 0.0 ):

0.00

ESTIMATED TOTAL:

4286451.50

----------------------------------------------------------------------------------------------------------------------------------

A-308

Exhibit E4- ABC Conceptual Cost Estimate Survey Responses
Initial ABC Questions

State

In your experience, did you conclude that conventional or
prefabricated bridges were more cost efficient?

When would it be advised to apply a different method than Design-BidBuild contracting
method?

Which portion of ABC did you find
to be the most costly through your estimation
research?

What were the contractors biggest concerns when it
came to ABC construction costs?

How did the federal and state
requirements affect the cost and duration of the project?

What environmental factors play a
significant role in ABC construction and how do they affect the overall cost
of projects?

Louisiana

This is a very general question, would depend on the scope of the project and the bridge type used

If early contractor MOT and traffic input is warranted management plans based on a high level to meet the ABC of risk such as MOT requirements, issues on high ADT accelerated routes and/or the schedules that acceleration of large increase costs. projects or programs.

Risks to meet accelerated project schedules.

FHWA now

MOT concerns with

requires a traffic local communities.

management plant

or TMP based on

the project scope

and can affect the

contractor's

schedule.

Utah

Costs are defined based ABC is evaluated for ABC costs are

Risks to meet

FHWA now

Environmental

on the goals of the

all projects within all dependent on the accelerated project requires a traffic constraints make ABC

project.

contracting methods. project.

schedules.

management plant a viable option for

or TMP based on projects - limiting

the project scope onsite construction

and can affect the time.

contractor's

schedule.

A-309

Initial ABC Questions

State

In your experience, did you conclude that conventional or
prefabricated bridges were more cost efficient?

When would it be advised to apply a different method than Design-BidBuild contracting
method?

Which portion of ABC did you find
to be the most costly through your estimation
research?

What were the contractors biggest concerns when it
came to ABC construction costs?

How did the federal and state
requirements affect the cost and duration of the project?

What environmental factors play a
significant role in ABC construction and how do they affect the overall cost
of projects?

Hawaii

If the contractor has In emergencies and Not available.

adequate time with no other situations

restrictions on opening where a highway

the bridge to traffic, needs to be opened to

conventional

traffic very quickly

construction techniques as a result of a

may be more cost

catastrophic event or

effective. Prefabrication complete closure of a

of girders has been

highway or bridge

proven to be cost

for construction, etc.

effective because it can

eliminate forming and

shoring. However,

prefabricating bridges

and other components of

bridges to minimize

construction time and

inconveniences to the

traveling public is not

necessarily cost

effective. The major

benefit is that the bridge

can be opened to traffic

faster thereby

inconveniencing the

public less.

Finding qualified No significant

precasting

effect

fabricators is always

a problem in Hawaii.

We have only one

fabricator that is

certified and only

for specific

products.

Permits and environmental clearances play a major part in any project. In some cases, use of ABC techniques such as prefabrication of girders can eliminating permits required if constructing within a stream by completely spanning over the affected area saving some cost in design and construction.

New Jersey #1

Conventional bridges are NJDOT uses ABC Production and

more cost efficient,

construction, A+B Erection of Pre-

because you have more Bidding and

Cast Structure was

contractors bidding on Incentive/Disincentiv most costly on my

the jobs, you do not need e provisions only project.

large cranes, or special when the anticipated

materials for the closure traffic impacts are

pours.

significant and

cannot be staged or

detoured

permanently.

It was critical for the The federal/state Seasonal restrictions to

contractors' to have government

construct ABC bridge

the best estimate, be encourages using must be clearly defined

awarded & monitor ABC technique in contract documents

the job closely,

where it is cost- and at times will cost a

effective planning effective and

little bit more when the

and timely execution benefits to road construction window is

of ABC structural users are

narrow.

members.

significant.

NJDOT's priority

is minimizing

traffic impacts and

construction

duration at a

reasonable

additional cost.

A-310

Initial ABC Questions

State

In your experience, did you conclude that conventional or
prefabricated bridges were more cost efficient?

When would it be advised to apply a different method than Design-BidBuild contracting
method?

Which portion of ABC did you find
to be the most costly through your estimation
research?

What were the contractors biggest concerns when it
came to ABC construction costs?

How did the federal and state
requirements affect the cost and duration of the project?

What environmental factors play a
significant role in ABC construction and how do they affect the overall cost
of projects?

NewJersey On our project, I believe We used A+B

The cost of the The only major

On my project, the ABC construction can be

#2

the ABC bridges were very Bidding

precast structure concern of the

federal and state a benefit in reducing the

competitive in terms of cost (Incentive/Disincenti was the most costly contractor on my requirements were duration of impact on

to conventional

ve) on the Route 1

construction. We replaced three single-span bridges in

Freeway ABC

three separate weekends. projects because it

part of the ABC effort on my project.

ABC project was the typically the same environmental factors.

penalty or

whether utilizing

More and more of the environmental regulations

disincentive of not conventional

tend to impact the

Costs for the Maintenance allowed the

meeting the deadline construction or construction season and

and Protection of Traffic Department to obtain

in opening the

ABC construction. the time available for

over a long duration were bids that considered

roadway back up to My team did not construction. ABC

avoided. Traffic impacts to the construction

traffic in time.

see any significant construction can be done

motorists were during a duration/schedule.

difference.

in a fraction of the time of

weekend period that only On each of the three

impacted discretionary

bridges, the

traffic and not the high

contractor beat the

volume workday traffic.

The design of certain ABC deadline and opened

or precast composite

the three bridges

structures/bridges can

ahead of schedule,

conventional construction. This means ABC construction can be completed, in a narrow environmental window, without the need for additional mobilizations

actually be less costly than which was important

from the contractor.

a conventional bridge

for the heavily travel

Completion of

because the precast

and congested Route

construction in a short

manufacturer completes 1 Corridor. much of the design.

time can also reduce the risk or delay claims when

the project is constructed

over more than one

construction season.

California

When considering just

Projects that present In the case of the 3 The California bridge We do not have

structure costs conventional challenges in the area main ABC methods construction industry is information on this

methods tend to be less of constructability, (precast, slide-in, and built upon cast-in- topic.

expensive unless the site is staging, and

large bridge moves) place concrete bridges.

a long distance from the constrained work

we have found, based Contractors have

nearest batch plant, in

windows would benefit on limited experience invested heavily over

which case the precast

from the innovation and in state and through the years in training

alternative can be less

practical feedback

evaluation national their labor force and

expensive. However, one delivered by the

data, that large bridge purchasing forms and

must consider costs of the Contract

moves are the most false work for this type

overall project to properly Manager/General

expensive, followed of construction.

evaluate the most cost

Contractor (CM/GC) by slide-in, then

efficient alternative.

method.

precast.

Wetland mitigation plays a large role in ABC construction. Wetlands impacted by conventional construction must be mitigated by up to a 10:1 ratio (for each square foot of wetland impacted, 10 square feet must be developed elsewhere) and then the new wetlands must be monitored for years after the project is complete.

A-311

Initial ABC Questions

State

In your experience, did you conclude that conventional or
prefabricated bridges were more cost efficient?

When would it be advised to apply a different method than Design-BidBuild contracting
method?

Which portion of ABC did you find
to be the most costly through your estimation
research?

What were the contractors biggest concerns when it
came to ABC construction costs?

How did the federal and state
requirements affect the cost and duration of the project?

What environmental factors play a
significant role in ABC construction and how do they affect the overall cost
of projects?

Maryland

Maryland does not have When design time is Don't have enough Time constraints is Some ABC

Maryland is often

much cost data

limited, design-bid information to

the biggest concern. methods /

cautious to try new

comparing the two. Our build offers an

respond to this. ABC methods are technologies are methods of

limited information does advantage of being

often used with

proprietary so it is construction and new

conclude that

able to be under

extremely time

difficult to get materials when there is

prefabricated elements construction and

constrained projects, exactly what you uncertainty of how it

tend to be more

designing at the same

which often include want since sole will perform long term

expensive. The decision time.

large monetary

sourcing is not under environmental

to use them, however, is

penalties for not allowed. This is influences.

based on many other

meeting deadlines. an area where

factors such as time and

ABC methods are design / build can

durability.

often new to

be advantageous.

***(Maryland's typical

contractors and they

ABC project is the use

are unsure how to

of prestressed slab to

handle the risk in the

replace small rural

bidding process.

bridges. The typical cost

for this type of bridge is

$225 per square foot.

Iowa

The direct cost of

Tight overall

N/A

prefabricated (ABC) schedule (design and

bridges tend to be more construction) would

expensive but they

make Design-Build

become more cost

method more

efficient if you consider favorable if allowed

the indirect cost (cost by state laws.

incurred by the traveling

public).

Very short schedule Not a factor. requires contractors to anticipate high dollar liquidated damages in their bids. Also, having subcontractors (precasters) take significant amount of their work.

Environmental issues can be minimized by ABC methods, so they do not play a significant role. However, this is always on a case by case basis.

A-312

Initial ABC Questions

State

In your experience, did you conclude that conventional or
prefabricated bridges were more cost efficient?

When would it be advised to apply a different method than Design-BidBuild contracting
method?

Which portion of ABC did you find
to be the most costly through your estimation
research?

What were the contractors biggest concerns when it
came to ABC construction costs?

How did the federal and state
requirements affect the cost and duration of the project?

What environmental factors play a
significant role in ABC construction and how do they affect the overall cost
of projects?

Florida

This depends on many In Florida, almost all In Florida, almost RISK. Many ABC This varies on

factors. The size of the projects cost more all projects cost projects contain every project and

bridge is a major factor. using ABC methods. more using ABC incentive/disincentiv there is no good

The larger the bridge the I believe you will methods. I believe e clause and they single answer.

more repetition and thus find this is true of you will find this is usually bid assuming

the most cost efficient it projects across many true of projects the incentive will be

is to use prefabricated states. The real cost across many states. realized. If

elements. It is almost savings is in the

The real cost

something delays the

impossible to be cost reduction in what is savings is in the project the risk in

effective with unique called user delay reduction in what is loosing the incentive

prefabricated elements costs. The costs of called user delay and pay

on small structures.

sitting in traffic and costs. The costs of disincentives is a

Using standardized

moving slower. This sitting in traffic and real issue.

prefabricated elements is frequently more moving slower.

across the state on

costs than he actual This is frequently

numerous projects does construction costs more costs than he

aid greatly in making increases for using actual construction

prefabricated elements ABC. ABC is best costs increases for

more cost effective on utilized when there is using ABC.

small projects.

an overall cost

savings approach

realized, not just

construction dollars.

Many times with ABC methods, the environmental exposure is decreased either with more efficient construction methods or shorter periods of disturbance. For large waterborne projects, the cost is usually less than using conventional methods.

A-313

State Michigan

Revised Questions

Based on your experience with ABC,
are prefabricated bridges more costly than conventional
bridges?

Have you ever used another contracting
method besides Design-Bid-Build for ABC? If yes,
under what circumstances?

What ABC elements have been more costly than conventional
bridge construction?

Have any of your contractors had cost concerns when
using ABC?

Did federal and/or state requirements affect the overall
ABC cost/duration of the project? If
yes, how?

What, if any, environmental factors/policies affected your ABC projects? How did these affect the overall cost?

Yes. A little, but hard to Yes, CMGC

Elements we have If the project

No

No

place hard values on.

done a precast

progress schedule

Probably about 10 more

abutment walls, would make cast in

per project.

pier columns, pier place construction

caps, decked

feasible, the

beams. I can not contractor will value

say that any of engineer the project

these was

to remove PBES.

significantly more

costly than others.

South Dakota Not a lot of experience No with ABC but we would say yes.

Pre-cast deck units No and pre-cast sleeper slabs for us

No

None on our limited

projects

Minnesota Yes

Yes. CMGC and Design Build. We evaluate the characteristics of each project to determine the contract administration method.

Full depth deck Yes, have asked to No

panels. Precast do the work using

substructure units, conventional

inverted tee

methods.

superstructures.

Illinois

Our first projects are in No, not yet. plan development so we don't have cost history yet.

No cost data yet. No concerns known No yet.

Use of precast products in lieu of castin-place concrete over water is generally faster and less likely to cause environmental issues, but is more expensive.
Not yet

A-314

State Missouri

Revised Questions

Based on your experience with ABC,
are prefabricated bridges more costly than conventional
bridges?

Have you ever used another contracting
method besides Design-Bid-Build for ABC? If yes,
under what circumstances?

What ABC elements have been more costly than conventional
bridge construction?

Have any of your contractors had cost concerns when
using ABC?

Did federal and/or state requirements affect the overall
ABC cost/duration of the project? If
yes, how?

What, if any, environmental factors/policies affected your ABC projects? How did these affect the overall cost?

Yes

Yes. We did a single We haven't

We don't have

No federal

N/A

contract design-build identified

enough experience requirements. We

project to replace individual

to answer this one. have had a few

554 bridges across elements. We just

isolated incidents

the state. One of the see an increase in

where we were

main goals was to all the pay items.

willing to pay a

build the replacement

higher price for

bridges quickly.

faster bridge

construction to

limit the number

of days of head-to-

head traffic on

interstate.

North Dakota We have no direct

N/A

experience with ABC

construction.

N/A

N/A

N/A

N/A

Kansas

Yes, our attempt to let an No. KDOT is

Precast columns;

ABC bridge project prohibited by Kansas precast pier caps;

using Prefabricated

law from using

precast abutment

Bridge Elements cost Design-Build or grade beams;

more than $1 million CM/GC. (There was precast deck

more than a

on special exception sections.

conventional bridge. made for a large

interchange project

in Kansas City to use

Design-Build.)

We attempted one The one ABC No environmental

ABC bridge project project was

factors weighed on the

and let it twice. Both attempted was ABC project we

times, the cost of the financed in a

attempted.

ABC bridge was conventional

more than the cost of manner with a mix

the conventional + of sate and federal

local detour. The funds, without any

contractors were special grants.

"concerned" that we KDOT chose a

did not go ahead and schedule based on

award the bids. We local concerns and

rejected both bids a reasonable

and are in the

traffic closure (30

process of

days) for the ABC

redesigning the

methods

bridge to use

employed.

conventional

construction.

A-315

Revised Questions

State

Based on your experience with ABC,
are prefabricated bridges more costly than conventional
bridges?

Have you ever used another contracting
method besides Design-Bid-Build for ABC? If yes,
under what circumstances?

What ABC elements have been more costly than conventional
bridge construction?

Have any of your contractors had cost concerns when
using ABC?

Did federal and/or state requirements affect the overall
ABC cost/duration of the project? If
yes, how?

What, if any, environmental factors/policies affected your ABC projects? How did these affect the overall cost?

Pennsylvania

Based on typical unit A. Recently

Primarily the

Contractor's has One issue is the Not aware of any

bridge construction costs completed 581

precast pieces for various concerns various rules in environmental issues.

we typically spend about project in Harrisburg, full height

with ABC projects. determining/calculat

$250/SF but a

we bid that

prefabricated ABC

superstructure

bridge is around $450/sf. replacement with

abutments. These The primary issue is ing the "liquidated

full height

the very tight

damages" if the contract completion

abutment pieces are timeframes to

date is exceeded.

ABC as a Design relatively heavy complete the project The rules in

Build. This project and thus require and the risk of

calculating

was recently

large cranes. The liquated damages if liquidated damages

presented via the FIU cost to rent a large the project is not are such that for low

WebEx.

crane to set the completed per the volume roads the

B. A couple of years pieces is a

ago a contractor

significant cost

submitted a value factor.

engineering proposal

to change a stage

construction bridge

contract schedule.

cost for liquidated damages is minimal thus contractors ignore the use of ABC and go conventional by simply including in

to an all precast ABC

the contract bid the

bridge.

costs for liquidated

damages. Thus, the

rules for calculating

liquidated damages

need to be revised.

A-316

APPENDIX F ABC DECISION-MAKING TOOLS
A-317

APPENDIX F - ABC DECISION-MAKING TOOLS

% Weight

Category

Decision-Making-Item Railroad on Bridge?

Possible Points
8

Points

Allocated

Scoring Guidance

0

No

4 Yes: Little Traffic

8 Yes: Heavy Traffic

Railroad Under Bridge?

3

17%

Disruptions (on/under
Bridge)

0

No

Yes: Minor Railroad

1

Track

Yes: Major Railroad

3

Track

Over Navigation Channel

that needs to remain open?

6

Emergency Replacement?

8

8%

Urgency

ADT and/or ADTT

6

23%

User Costs and Delays

(Combined Construction Year ADT on and under
bridge)

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0

No

Yes: Minor amount

3

of traffic

Yes: Considerable 6 amount of traffic

0

No

Yes: Minor

4

Roadway

Yes: Major

8

Roadway

0 No Traffic Impacts

1

< 10,000

2 10,000 to 25,000

3 25,000 to 50,000

4 50,000 to 75,000

Required Lane

Closure/Detours?

6

(Length of Delay to Traveling Public)

Are only Short Term

Closures Allowable?

5

Impact to Economy?

6

(Local Business Access, impact to manufacturing,
etc.)

Impacts Critical Path of the

Total Project?

6

14%

Construction Time

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5 75,000 to 100,000 6 100,000 or more

0 Delay 0-5 minutes

1

5-10 minutes

2 15-25 minutes

3 25-35 minutes

4 35-45 minutes

5 45-55 minutes

6 55 or more minutes

Available alternatives for 0 staged construction

Available

alternatives for

staged construction,

3

undesirable

No available

5

alternatives

0 Little to no impact

3 Moderate impact 6 Considerable Impact
0 Little to no impact 3 Moderate impact 6 Considerable Impact

Restricted Construction

Time

8

(Environmental schedules, Economic Impact - e.g. local business access,
Holiday schedules, special events, etc.)

Does ABC mitigate a

5

critical environmental

impact or sensitive

environmental issue?

5% Environment

Compare Comprehensive

Construction Costs

3

(Compare conventional vs.

prefabrication)

3%

Cost

Does ABC Allow

Management of a

Particular Risk?

6

18%

Risk Management Safety (Worker Concerns)

6

A-320

0 No restrictions 3 Minor restrictions

Moderate

6

restrictions

Considerable

8

restrictions

0

No

2

Minor

3 Several Minor

4

Considerable

Several

5

Considerable

25% or higher than

0

conventional

1% to 25% higher 1 than conventional

Equal to

2

conventional

Lower than

3

conventional

Determine if risks can be managed 0-6 through ABC that aren't discussed in
other topics

0

TMP type 1

3

TMP type 2

6

TMP type 3-4

Safety (Traveling Public

Concerns)

6

Economy of Scale

5

(Repetition of components in a bridge or bridges in a
project)

(Total spans = sum of all spans on all bridges on the
project)

12%

Other

Weather Limitations for

Conventional

Construction?

2

0

TMP type 1

3

TMP type 2

6

TMP type 3-4

0

1 span

1

2 spans

2

3 spans

3

4 spans

4

5 spans

5 6 or more spans

0

No

1

Moderate

2

Considerable

Use of Typical Standard

Details (Complexity)

5

Sum of Points:

0

No

3

Some

5

All details

max. 100 Possible Points

A-321

Decision-Making Item Railroad on Bridge?
Railroad under Bridge?
Over Navigation Channel that needs to remain open?
Emergency Replacement?

Scoring Guidance Description
This is a measure of how railroad traffic on the bridge will be affected by the project. If a major railroad line runs over the bridge that requires minimum closures and a shoo fly (a temporary railroad bridge bypass) cannot be used, provide a high score here. If a railroad line that is rarely used runs over the bridge, consider providing a mid-range or low score here. If there is no railroad on the bridge, assign a value of zero here.
This is a measure of how railroad traffic under the bridge will be affected by the project. If a major railroad line runs under the bridge that would disrupt construction progress significantly, provide a high score here. If a railroad track runs under the structure, but it is used rarely enough that it will not disrupt construction progress significantly, provide a low score here. Consider if the railroad traffic is able to be suspended long enough to move a new bridge into place. If there is not a large enough window to move a new bridge into place, SPMT could be eliminated as an alternative for this project. For this case, PBES may be a more applicable alternative. If there is no railroad under the bridge, assign a value of zero here.
This is a measure of how a navigation channel under a bridge will be affected by the project. If a navigation channel is highly traveled and needs to remain open for shipments, provide a high score here. If a navigation channel is rarely traveled and there are not requirements for it to remain open at certain time periods, provide a low score here. If there is no navigation channel under the bridge, assign a value of zero here.
This is a measure of the urgency of the bridge replacement. A more urgent replacement supports the use of accelerated bridge construction methods, since demolition and construction can be progressing concurrently. Depending on the particular project, accelerated bridge construction methods can also allow multiple components of the bridge to be constructed concurrently. If the bridge replacement is extremely urgent and the bridge can be replaced quicker by using accelerated construction methods, provide a high score here.
A-322

ADT and/or ADTT (Construction Year)
Required Lane Closures/Detours?
Are only Short Term Closures Allowable?
Impact to Economy
Impacts Critical Path of Total Project?

This is a measure of the total amount of traffic crossing the bridge site. A higher ADT value at a site will help support the use of accelerated bridge construction methods. Use a construction year ADT value equal to the sum of the traffic on the structure and under the structure. For cases where there is a very high ADT on the bridge and very low or no ADT under the bridge, consider using a "slide" method (on rollers or Polytetrafluorethylene (PTFE)/Elastomeric pads) or SPMT's, which can be very cost effective ABC techniques for this situation. For structures with a higherthan-average percentage of truck traffic, consider providing a higher score than indicated solely by the ADT values in the table.
This is a measure of the delay time imposed on the traveling public. If conventional construction methods will provide significant delays to the traveling public, provide a high score here. If conventional construction methods will provide minimal delays to the traveling public, provide a low score here. Use the delay times provided in the table as guidance for scoring.
This is a measure of what other alternatives are available besides accelerated bridge construction. If staged construction is not an alternative at a particular site, the only alternative may be to completely shut down the bridge for an SPMT move, and therefore a high score should be provided here. If there is a good alternative available for staged construction that works at the site, a low score should be provided here.
This is a measure of the impact to the local businesses around the project location. Consider how the construction staging, road closures, etc. will impact local businesses (public access, employee access, etc.) A high impact to the economy equates to a high score here. A low impact to the economy equates to a low score here.
This is a measure of how the construction schedule of the structure impacts the construction schedule of the entire project. If the construction of the structure impacts the critical path of the entire project, and utilizing ABC methods provides shorter overall project duration, provide
A-323

Restricted Construction Time

a high score here. If other project factors are more critical for the overall project schedule and utilizing ABC methods will not affect the overall project duration, provide a low score here.
This is a measure of how the construction schedule is impacted by environmental and community concerns or requirements. Items to consider are local business access windows, holiday schedules and traffic, special event traffic, etc. If there are significant restrictions on construction schedule, provide a high score here. If there are little to no restrictions on the construction schedule, provide a low score here.

Does ABC mitigate a critical environmental impact or sensitive environmental issue?
Compare Comprehensive Construction Costs

This is a measure of how using accelerated bridge construction methods can help mitigate impacts to the environment surrounding the project. Since accelerated methods allow a shorter on-site construction time, the impacts to the environment can be reduced. If the reduced on-site construction time provided by accelerated bridge construction methods mitigates a significant or critical environmental concern or issue, provide a high score here. If there are no environmental concerns that can be mitigated with accelerated construction methods, provide a low score here.
This is a measure of the complete comprehensive cost difference between conventional construction methods versus using an accelerated bridge construction method. Some costs will increase with the use of accelerated construction methods, such as the cost of the SPMT equipment and the learning curve that will be incorporated into using new technologies. However, some costs will decrease with the use of accelerated construction methods, such as the reduced cost for traffic control, equipment rentals, inspector wages, etc. Many of the reduced costs are a direct result of completing the project in less time. Use the cost comparisons in the table as guidance for scoring here.

A-324

Does ABC allow management of a particular risk?
Safety (Worker Concerns)
Safety (Traveling Public Concerns)
Economy of Scale
Weather Limitations for Conventional Construction?

This is an opportunity to add any project-specific items or unique issues that have risk associated with them that are not incorporated into another section in this text. Consider how ABC may or may not manage those particular risks.
This is a measure of the relative safety of the construction workers between conventional construction methods and accelerated construction methods. The reduced on-site construction time from using accelerated bridge construction methods reduces the exposure time of workers in a construction zone, thus increasing safety. If a significant increase in safety can be seen by utilizing accelerated construction methods, provide a high score here. If utilizing accelerated construction methods does not provide additional safety, provide a low score here.
This is a measure of the relative safety of the traveling public between conventional construction methods and accelerated construction methods. The reduced on-site construction time from using accelerated bridge construction methods reduces the exposure time of the traveling public in a construction zone, thus increasing safety. If a significant increase in safety can be seen by utilizing accelerated construction methods, provide a high score here. If utilizing accelerated construction methods does not provide additional safety, provide a low score here.
This is a measure of how much repetition is used for elements on the project, which can help keep costs down. Repetition can be used on both substructure and superstructure elements. To measure the economy of scale, sum the total number of spans that will be constructed on the project. For example, if there are 2 bridges on the project that each have 2 spans, the total number of spans on the project is equal to 4. Use the notes in the table for scoring guidance here.
This is a measure of the restrictions that the local weather causes for on-site construction progress. Accelerated bridge construction methods may allow a large portion of the construction to be done in a controlled facility, which helps reduce delays caused by inclement weather (rain, snow, etc.). Depending on the location and the season,
A-325

Use of Typical Standard Details (Complexity)

faster construction progress could be obtained by minimizing the on-site construction time.
This is a measure of the efficiency that can be gained by using standard details that have already been developed and approved. If standard details are used, some errors in the field can be prevented. If new details are going to be created for a project, the contractors will be less familiar with the details and problems may arise during construction that were not considered in the design phase. Use the notes in the table for scoring guidance here.

A-326

F1 Decision Making Flowchart (adapted WisDOT, 2015)
Identify a need or opportunity for ABC

ABC Rating of 50+ points

ABC Rating 49 to 21 points

ABC Rating of 0 to 20

Faster implementation of bridge

No

with ABC?

Yes

Do the overall advantages of ABC negate any additional costs? (Consider schedule, traffic impacts, funding, user costs, etc.)

No

Yes

Do the site location allow for an ABC approach?
Yes
Develop a useful ABC approach for the project

Program

Yes

Initiative

No

No

Use conventional construction method

Alternate Contracting Media Outreach

Objective to reduce bridge/roadway out- of-service time?
Yes

Is there a location to build the bridge off

No

No

site?

Yes
Any window of time available to close the

No

bridge to move in a new bridge?

Yes

Slide

SPMT

Consider another ABC Alternative, Conventional Construction Method, or
Alternate Contracting

Objective to Minimize Total Project Construction Window?
Yes
Are site conditions appropriate for PBES or GRS?
Yes

PBES

GRS-IBS

A-327

APPENDIX G ABC TOOLKIT TEMPLATE
A-328

APPENDIX G - ABC TOOLKIT TEMPLATE The summary of ABC toolkit components below can be used as a template of the web-based toolkit.

ABC Components

Contents

Decision-Making Tool Decision-making matrix

Decision-making flowchart

Design

Design concepts

Pre-design examples

Design aides

Construction

Construction guidelines

Construction flowcharts

Risk Analysis

Risk analysis guidelines

Interactive flowcharts

Cost Estimates

Cost estimates guidelines

Examples of cost estimates

Related Chapters from the Final Report
CHAPTER 3 APPENDIX F
CHAPTER 4 APPENDIX B APPENDIX H
CHAPTER 7 APPENDIX C
CHAPTER 5 APPENDIX D
CHAPTER 6 APPENDIX E

A-329

APPENDIX H DESIGN AIDES Using Mathcad
A-330

APPENDIX H - DESIGN AIDES Using Mathcad
An analysis of the superstructure can be performed using structural modeling software or computational aide to calculate the design moments, shears, and reactions. However, the SHRP2 design examples just provided the results from finite element analyses. It is desirable that this toolkit can be used without any additional computational supports from other sources. Therefore, this study provided the Mathcad examples to evaluate the maximum design loadings using qBridge software, a Mathcad program developed by Professor Emeritus, Noyan Turkkan at the University of Montana, Canada. Dr. Turkkan granted a permission to use this software for this project. The Authors gratefully acknowledge his permission and support.
H1-Mathcad Examples to calculate the design loadings for concrete decked steel girder examples
1. Design loadings for girders (Design Step 10. Load Results. Case 4)
1) 80ft span - Design Loads-Steel Girder-80ft-MDC4.xmcd - Design Loads-Steel Girder-80ft-MDW4.xmcd - Design Loads-Steel Girder-80ft-MLL4.xmcd - Design Loads-Steel Girder-80ft-MLL4_neg.xmcd
2) 60ft span - Design Loads-Steel Girder-60ft-MDC4.xmcd - Design Loads-Steel Girder-60ft-MDW4.xmcd - Design Loads-Steel Girder-60ft-MLL4.xmcd - Design Loads-Steel Girder-60ft-MLL4_neg.xmcd
3) 40ft span - Design Loads-Steel Girder-40ft-MDC4.xmcd - Design Loads-Steel Girder-40ft-MDW4.xmcd - Design Loads-Steel Girder-40ft-MLL4.xmcd - Design Loads-Steel Girder-40ft-MLL4_neg.xmcd
2. Design loadings for deck (Design Step 21. Load Results) - Design Loads_Deck_MDC.xmcd - Design Loads_Deck_MLL.xmcd
Note: The electronic files of these Mathcad examples are provided through an external hard drive or email.
A-331

H2- AASHTO HL-93 Loading
The AASHTO HL-93 loading is a hypothetical live load model proposed by AASHTO for analysis of high bridges. Reason for proposing this live load model is to prescribe a set of loads such that it produces an extreme load effect approximately same as that produced by the exclusion vehicles. Exclusion vehicles were the vehicles above the legal limit but due to grand fathering provision in the state they were allowed to operate routinely.
It has 3 basic live loads for bridges called HL-93 Loading, where H stands for highway and L stands for Loading, developed in 1993.
1. Design Truck 2. Design Tandem 3. Design Lane
1. Design Truck
It is commonly called as HS-20 44 (where H stands for highway, S for semi-trailer, 20 TON weight of the tractor (1st two axles) and was proposed in 1994).
2. Design Tandem
It consists of two axles weighing 25 kips (110 KN) each spaced at 4 ft (1.2 m).

3. Design Lane

Figure H1. HS-20 truck and tandem loadings

It consists of uniformly distributed load of 0.64 kip/ft (9.3 N/mm) and assumed to occupy 10 ft (3 m) transversely.

Figure H2. Lane loading

A-332

Design loading is the maximum of the three cases: 1. Design Tandem + Design Lane: referred as HL-93M 2. Design Truck + Design Lane: referred as HL-93K 3. 90% of (2 Design Trucks + Design Lane): referred as HL-93S
Figure H3. HL-93 load cases.
A-333

File Name: Design Load-Steel Girder-80ft-MLL4.xmcd

qBridge

Quick analysis of bridge structures x User defined moving truck x Multiple span continuous bridge beams, EI constant x Moment and shear (absolute value) envelopes x Support reactions x Lane load

USAGE :



M R



:= qBridge(T,B)

T : Truck definition B : Bridge definition M : Vector (4 x 1) - xcoordinates, Vmax, Mmin and Mmax R : Vector (2 x 1) - Support reactions : Rmin and Rmax

Truck definition : a matrix of nAxles x 2 First column: Axle x-coordinates in ascending order (not axle spacing), beginning with 0 (zero). Second column: axle weights Note: there must be at least two (2) axles.

INPUT

HS20

0 81.33



14

321.33

28 321.33

80 0.64 10

B



80

0.64

10

80 0.64 10

TD 0 251.33 4 251.33

x This program is wrien using Mathcad 14.0 M020. x This program was developed by Professor Emeritus, Noyan Turkkan at
the University of Montana. He granted a permission to use this Soware for this project. The Authors gratefully acknowledge his permission and support.
Bridge definition : a matrix of nSpans x 3 First column: span lengths Second column: uniform load (lane load) on the corresponding span Third column: number of divisions on a span. Critical values of shears and moments are computed on each division point along the beam.
Notes: Truck will move in one direction only. Reverse the truck geometry to simulate moving in the other direction. Consistent units must be used (for example : Kips and feets or kN and m). When using two or more spans, lane loads should be applied in a checkerboard fashion in order to obtain maximum (or minimum) moments, shears and reactions. IM (Impact Factor)= 33% Design values= LLDF*Maximum Values Where, LLDF= live load distribution factor, and Maximum Values calculated from this MathCAD program

A-334

qBridge routines
Example : 3-span bridge beam with HL-93 loading (HS-20 and Tandem) 2 LC shown here. Loa



M1 R1





qBridge(HS20 B)

Loading case 1 envelopes

x M11

Vmax1 M12

Rmin1 R11

Loading case 2 envelopes Vmax2 M22

Rmin2 R21



M2 R2





qBridge(TDB)

Mmin1 M13 Rmax1 R12

Mmax1 M14

Mmin2 M23 Rmax2 R22

Mmax2 M24

n rows(x) i 1 n

m rows(Rmin1) j 1 m

A-335

Resulting envelopes
Vmaxi max Vmax1iVmax2i Rminj min Rmin1j Rmin2j

Mmini min Mmin1iMmin2i Rmaxj max Rmax1j Rmax2j

Mmaxi max Mmax1iMmax2i

Moment envelopes

xh xn

yv1 1.2round(max(Mmax)) yv2 1.2round(min(Mmin))

yv3 1.2round(max(Vmax))

1u103

Mmax

Mmin

0

1u103

0

100

200

x Shear envelopes (absolute values)

A-336

100 Vmax
50
0 0

x 1

1

0

2

8

3 16

4 24

5 32

6 40

7 48

8 56

9 64

10 72

11 80

12 88

100 x

Mmin 1

1

0

2

0

3

0

4

0

5

0

6

0

7

-96

8

-255.4

9

-455.7

10

-697

11 -1146.6

12 -870.2

Mmax 1

1

0

2 656.9

3 1102.7

4 1407.7

5 1511.2

6 1486.8

7 1284.6

8 930.6

9

475

10

21.4

11

0

12

0

200
Vmax 1
1 96.3 2 79.6 3 63.2 4 47.4 5 32.3 6 37.3 7 53.1 8 68.2 9 82.4 10 95.6 11 107.7 12 93.1

A-337

12 88 13 96 14 104 15 112 16 ...

12

870.2

13 -634.7

14 -440.2

15 -286.6

16

...

12

0

13 396.7

14 776.5

15 1001.3

16

...

Rmin 1
10 20 30 40

Rmax 1
1 96.3 2 150.4 3 150.5 4 88.5

12 93.1

13 77.7

14 61.8

15 45.8

16

...

A-338

File Name: Design Loads_Deck_MLL.xmcd

qBridge

Quick analysis of bridge structures x User defined moving truck x Multiple span continuous bridge beams, EI constant x Moment and shear (absolute value) envelopes x Support reactions x Lane load

USAGE :



M R



:= qBridge(T,B)

T : Truck definition B : Bridge definition M : Vector (4 x 1) - xcoordinates, Vmax, Mmin and Mmax R : Vector (2 x 1) - Support reactions : Rmin and Rmax

Truck definition : a matrix of nAxles x 2 First column: Axle x-coordinates in ascending order (not axle spacing), beginning with 0 (zero). Second column: axle weights Note: there must be at least two (2) axles.

INPUT

0 25.54

HS20



6

25.54



12 0

TD 0 0 4 0

This program is wrien using Mathcad 14.0 M020

3 0 4

2



11

0

4

12



2



11 12

0

4


3 1 0 4 12

2



11

0

4

12



B 3 0 4

2



11

0

4

12





3



1 12

0

4







2 11 0 4

12

2



11 12

0

4


3 0 4

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qBridge routines





Example : 2-span bridge beam with HL-93 loading (HS-20 and Tandem) 2 LC shown here.



M1 R1





qBridge(HS20 B)

Loading case 1 envelopes

x M11

Vmax1 M12

Rmin1 R11

Loading case 2 envelopes Vmax2 M22

Rmin2 R21



M2 R2





qBridge(TDB)

Mmin1 M13 Rmax1 R12

Mmax1 M14

Mmin2 M23 Rmax2 R22

Mmax2 M24

n rows(x) i 1 n

m rows(Rmin1) j 1 m

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Resulting envelopes
Vmaxi max Vmax1iVmax2i Rminj min Rmin1j Rmin2j

Mmini min Mmin1iMmin2i Rmaxj max Rmax1j Rmax2j

Mmaxi max Mmax1iMmax2i

Moment envelopes

xh xn

yv1 1.2round(max(Mmax)) yv2 1.2round(min(Mmin))

yv3 1.2round(max(Vmax))

10 Mmax
Mmin 0

0

10

20

30

x

Shear envelopes (absolute values)

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30

20 Vmax
10

0

0

10

x 1

1

0

2 0.8

3 1.5

4 2.3

5

3

6 3.7

7 4.5

8 5.2

9 5.9

10 6.6

11 7.4

12 8.1

Mmin 1

1

0

2 -1.5

3

-3

4 -4.5

5 -7.8

6 -5.5

7

-5

8 -4.4

9 -6.3

10 -4.3

11 -4.5

12 -4.7

20 x

Mmax 1

1

0

2 13.1

3 15.3

4

9.2

5

1.6

6

9.2

7 12.9

8

9.1

9

2.1

10 9.7

11 13.5

12 9.6

30
Vmax 1
1 25.5 2 17.5 3 13.7 4 20.1 5 25.5 6 19.8 7 12.6 8 19.4 9 25.5 10 20.7 11 13.5 12 13.6

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12 8.1

13 8.8

14 9.6

15 10.4

16

...

12 4.7

13 -6.9

14 -4.3

15 -4.2

16

...

12 9.6

13 1.7

14 9.8

15 13.9

16

...

Rmin 1

1

-2

2 -3.2

3 -4.3

4 -3.4

5 -3.6

6 -3.7

7 -3.8

8 -3.6

9 -3.3

10 -4.3

11 -3.2

12 -1.9

Rmax 1
1 25.5 2 25.8 3 25.5 4 25.8 5 25.5 6 25.5 7 25.7 8 25.7 9 25.5 10 25.5 11 25.8 12 25.5

12 13.6

13 25.6

14 19.8

15 12.1

16

...

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Bridge definition : a matrix of nSpans x 3 First column: span lengths Second column: uniform load (lane load) on the corresponding span Third column: number of divisions on a span. Critical values of shears and moments are computed on each division point along the beam.
Notes: Truck will move in one direction only. Reverse the truck geometry to simulate moving in the other direction. Consistent units must be used (for example : Kips and feets or kN and m). When using two or more spans, lane loads should be applied in a checkerboard fashion in order to obtain maximum (or minimum) moments, shears and reactions.
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APPENDIX I IMPLEMENTATION PLAN
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APPENDIX I - IMPLEMENTATION PLAN The primary implementation of this toolkit is to share its contents with GDOT, LGs, and other local bridge professionals through the technology transfer activities. The proposed toolkit including currently available ABC-related information websites will be used as educational tools accordingly. Specific technology transfer activities were done as below.
Presentation at the 2015 National ABC Conference, December 7-8, 2015, in Miami, FL Presentation at the SHRP2 R04 Peer-to-Peer Workshop, November 18, Atlanta, GA In the future, using feedback obtained from GDOT, ABC Conference, and SHRP2 R04 Peer-to-Peer Workshop, the research team can develop specific implementation tasks such as outreach and training, including workshops, webinars, peer exchanges and demonstration projects for local governments in GA.
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