This manual has been developed for the purposes of enhancing the use of Prefabricated Bridge Elements and Systems (PBES) as part of accelerated construction projects. FHWA continues to focus on a need to create awareness, inform, educate, train, assist and entice State DOT’s and their staff in the use of rapid construction techniques.
This manual has been developed for the purposes of enhancing the use of Prefabricated Bridge Elements and Systems (PBES) as part of accelerated construction projects. FHWA continues to focus on a need to create awareness, inform, educate, train, assist and entice State DOT’s and their staff in the use of rapid construction techniques. This manual is a follow-up of a previously completed manual on Accelerated Bridge Construction (ABC). The purpose of this manual is to provide more in-depth information on the design, fabrication and erection of PBES. Significant portions of the previous ABC manual will be reproduced in this manual in order to provide a stand-alone document with minimal cross references.
Users of this manual will be able to perform the following tasks:
• Understand the different materials used in the construction of prefabricated bridge elements and systems.
• Understand the design requirements for the most common PBES technologies in use today.
• Understand how to design for durability using PBES.
• Understand how to specify PBES and design them for shipping and erection.Table of Contents
1 PURPOSE AND USE OF THE MANUAL
- Introduction
- Intended users
- Design Engineers
- Material Engineers
- Construction Engineering and Inspeccion Staff
2 MATERIALS FOR ABC AND PBES
- Cementitiuos materials
- Concrete
- Lighweight Concrete
- Grout for Post-Tensioning Ducts
- Flowable Fill
- Metals
- Steel
- Aluminum
- Polymers
- Fiber Reinforced Polymers
- Expanded Polystyrene
- Timber
- Other Proprietary products
- UHPC
- Thermoplastics
3 CURRENT LRFD DESING PROVISIONS
- Precast full depth deck units
- Partial depth deck panels
- Design of other deck systems
- Metal Grid Deck Panels
- Timber Decks
- Aluminum Decks
- Fiber Reinforced Polymer Decks
- Adjacent Beam/Deck Elements
- Mechanical connections-Reinforcing steel
- Post-Tensioning
- Seismic Design
- LRFD load Ratings
4 DESIGN OF SUPERSTRUCTURE ELEMENTS
- Adjacent Beam/Deck Elements
- Live load and Dead load distribution
- Transverse design of beam/Deck Elements
- Full Depth Precast concrete deck panels
- Geometry of Full depth deeck panel designs
- Size of deck panels
- Minimum deck panel thickness
- Design of main reinforcing
- Overhang and barrier design
- Design of longitudinal post-tensioning at transverse connections
- Design of mild reinforced transverse connections
- Design of longitudinal connections
- Design of Continuous bridges with full-depth deck panels
- Dead load distribution
- Shear connector design
- Haunch
- Design intergral Abutment bridges with depth deck panels
- Modular Elements
5 - DESIGN OF SUBSTRUCTURE ELEMENTS
- Design of prefabricated abutments and walls
- Cantilever Structures
- Integral Abutments
- Semi-Integral Abutments
- Geosynthectic reinforced soil integrated bridges system ( GRS-IBS )
- MSE Retaining walls
- Prefabricated modular retaining walls
- Soldier Pile retaining walls
- Backfilling
- DESIGN OF PREFABRICATED PIERS
- Pier Bents
- Wall Piers
- Desing of Pier Connections
- Seismic design
6 - DESIGN OF MODULAR CULVERTS
- Precast concrete box culverts
- Precast concrete arches and frames
- Corrugated metal pipe,arches,and frames
7 - DESIGN OF PREFABRICATED FOUNDATION ELEMENTS
- Spread footings
- Precast concrete spread footings
- Cast-In-Place concrete spread footings
- Combined precast and cast-in-plance concrete footings
- Bedding Under Footings
- Pile Caps
- Use of corrugated metal pipe voids
- Cast-in-place closure pours
- Precast columns connected to drilled shafts
- Pier Box Cofferdams
- Pile Bents
8 - DESING OF MISCELLANEOUS BRIDGES ELEMENTS
- Design
- Bridge deck Expansions joints
- Bearings
- Drainage Assemblies
- Railings
- Utility supports
9 - DESIGN FOR DURABILITY
- Jointless deck design
- Continuity/Post Tensioning
- Span-by-Spam Construction and link slabs
- Integral and semi-integral abutments
- Substructure connections
- Protection of critical connection
10 - TOLERANCES AND FABRICATION
- Tolerance requirements for design plans and specifications
- Element Size tolerance
- Element insert,Void,and projecting hardware tolerances
- Element horizontal erection tolerance
- Element horizontal erection tolerance
- Element vertical erection tolerance
- Effect of tolerances on the design and detailing of joints and connections
- Quality control
- Fabricator certifications
- Near-site fabrication
11 - DESIGN FOR SHIPPING HANDLING AND ASSEMBLY
- Element dimensions and weight
- Shipping of elements
- Handlings of elements
- Specifications requirements for bridge assembly
- Handling forces and stresses
- Strength requirements during assembly of prefabricated elements
- Design of bridges for large scale bridge mobeds
- Sources of Secondary Stresses during large scale bridge moves
- installations using self propelled modular transporters
- Installations using lateral sliding
- Effects of support points during deck casting
- Forces and stress during deck
12 - DESIGN EXAMPLES
- Bridge decks
- Integral abutment
- Cantilever abutment
- Pier Bent
- Wall Piers
13 - MATERIAL SPECIFICATIONS
- HIGH EARLY STRENGTH CONCRETES
- Use of Hidher Final Strenth mixes
- Design of the connection for a lower Initial Strenght
- Material Specification for High Early Strenght Concrete
- Post Tensioning systems
- Flowable fills
- Ultra high performance concrete
- Grouted Reinforcing splice couplers
14 - CONSTRUCTION SPECIFICATION
- Proprietary products
- Mechanical Couplers
- Post-tenstioning systems
- Assembly plans
- Installation fo Systems
References
15 APPENDIDEX A- ACCELERATED BRIDGE CONSTRUCTION DEFINITIONS
- Accelerated bridges construction
- Conventional bridges construction
- Time metrics for ABC
- Prefabricated bridge elements and systems ( PBES )
- Elements
16 APPENDIX GLOSSARY OF TERMS