This example demonstrates basic design features for design of a pier consisting of a concrete pier cap with rectangular columns supported on individual drilled shafts. The deck is the structural element that transfers vehicle and pedestrian loads to the girders. Policy on lrfd design of specific bridge superstructure components. Concrete deck slabs on i girders, ubeams, spread box beams, spread slab beams, steel plate girders, and steel tub girders materials geometric constraints design criteria detailing 3. Dec 17, 2019 lrfd steel girder superstructure design example manual for steel design, 5th edition by william t segui steel. May 10, 2015 lrfd design example for steel girder superstructure bridge us fhwa nhi 04041. Lrfd steel design p p nominal bearing capacity of concrete under base plate p u factored column load calculated from load factors in lrfd steel design r radius of gyration r generic load quantity force, shear, moment, etc. Comprehensive design example for prestressed concrete girder. In addition to different products, the grades of steel. The entire truss superstructure is made up of w14 x 109 members except for the bottom chord. Aashto lrfd design example for steel girder superstructure. The superstructure consists of two simple spans made continuous for live loads. In that example, girder design and detailing is evaluated extensively.
A steel angle is connected to the two piles and the. Design of deck reinforcement, including flexural resistance, limits of reinforcement, and control of cracking is based on aashto lrfd bridge design specifications 5. Based on the findings and results of nchrp project 121, the calculations presented herein expand on sbdh design example 3. The example illustrates the design of a typical threespan continuous straight steel i girder bridge with spans of 140. The four design examples covered in volume 4 include. Lrfd design of double composite box girder bridges core.
Lrfd steel girder design and rating stlrfd version 2. In addition to different products, the grades of steel available from each. The different girder and bridge types considered in the design examples are listed below, with a brief description of distin guishing features for each. It is analyzed as a continuous beam with the girders acting as supports. Sep 25, 20 the files attached include a csibridge model and a detailed pdf which documents the modeling and verification procedures for a composite steel girder bridge design based on the example published in the lrfd design example for steel girder superstructure bridge fhwa nhi04041 by fhwa in november 2003. Aashto lrfd bridge design specifications, 8th edition. Steel girder design example using 3rd edition aashto lrfd. When checking this limit state during a deck pour, use a multiplier of 0. Strength iii is used as a construction check for steel girder bridges with wind load but no live load. The t op flanges of compositelya designed plate girder are typically smaller than their bottom flanges. Policy on lrfd design of specific bridge substructure components.
For most projects, conventional materials should be specified. Deck design follows the nmdot standard deck slab detail in chapter 4 of the nmdot bridge procedures and design guide, hereinafter referred to as design guide. Load and resistance factor design lrfd for highway bridge. Section a6 flexural resistance sample calculation from opis to compare with. Nov 25, 2015 lrfd steel design aashto lrfd bridge design specifications example problems created july 2007.
Design step 5 design of superstructure prestressed concrete bridge design example task order dtfh6102t63032 52 notice that fatigue in the prestressing steel need not be checked for conventional prestressed girders s5. Design of substructure prestressed concrete bridge design example. Comprehensive design example for prestressed concrete psc. Superstructure design the superstructure design includes the following elements. Design step 5 design of superstructure prestressed concrete bridge design example task order dtfh6102t63032 582 design step 5. Sep 25, 2018 september 2018 lrfd bridge design 91 reinforced concrete decks on girders are the predominant type of deck used on highway bridges in minnesota. Pdf lrfd design example for steel girder superstructure bridge. Lrfd design example for steel girder superstructure bridge with commentary final submission us units. The traditional deck is placed as a single, castinplace concrete course 8 inches thick, which exceeds the. Lrfd example 4 2span precast prestressed i girder 6 deck design bpg effective length 9. Lrfd design example for steel girder superstructure bridge.
Design guidelines for bridge widenings, steel reinforced. Two general types of design loads are permanent and transient. In general, the calculations follow aashto lrfd 9th edition specifications 2020, or as modified based on the recommendations of nchrp 121. For superstructure member design, the component dimensions and the size and spacing of. Lrfd steel design ohio department of transportation. For this steel girder design example, a plate girder will be designed for an hl93 live load. Lrfd design example for steel girder superstructure bridge us. Design of beams flexural members part 5 of aisclrfd. In addition to general design guidance and information on detailing practices, this section contains three design examples. The steel girder design criteria are obtained from figures 3 1 through 33 shown below, from the concrete deck design example, and from the referenced articles and tables in the aashto lrfd. Chapter 3 superstructure design guidelines section 1 general recommendations bridge design guide 32 txdot january 2020 section 1 general recommendations prestressed concrete beam and girder design txdots policy is held firmly to a 6. The superstructure consists of two simple spans made continuous for. Design step 7 design of substructure prestressed concrete. File type pdf lrfd steel girder superstructure design example lrfd.
Design step 5 design of superstructure prestressed concrete bridge design example task order dtfh6102t63032 547 design step 5. This document consists of a comprehensive steel girder bridge design example, with instructional commentary based on the aashto lrfd bridge design. Design of a decked aashto pretensioned girder with harped cfrp cables example b4. Design step 7 design of substructure prestressed concrete bridge design example task order dtfh6102t63032 74 axis parallel to the girder s longitudinal axis and in the perpendicular direction. This design example is intended to provide guidance on the application of the aashto lrfd bridge design specifications when applied to prestressed concrete superstructure bridges supported on intermediate multicolumn bents and integral end abutments. Slab and psc i girder and a set of sample editable cad. Design step 7 design of substructure prestressed concrete bridge design example task order dtfh6102t63032 739 supported on the girders. Introduction to lrfd 18 resistance factors article 6. Detail design of psc i girder bridge deck girder superstructure in aashto lrfd. Design step 5 design of superstructure prestressed concrete bridge design example task order dtfh6102t63032 51 design step 5. Pdf lrfd design example for steel girder superstructure. Pdf detail design of psc igirder bridge deckgirder. Structural steels steel bridges are fabricated and constructed with steel elements that are produced at two different types of steel mills.
Structural design of composite bridges with steel plate. The design specifications used in these examples is the aashto lrfd bridge design. Four lrfd design examples of steel highway bridges, vol. Concrete deck slabs on adjacentframed beams slab beams and box beams materials. Design of a decked aashto posttensioned girder with draped cfrp cables references aashto lrfd 2017. For updates on the pensacola bay bridge visit fdot. In all cases, the appropriate multiple presence factor is applied. A twospan continuous composite i girder bridge has two equal spans of 165 and a 42 deck width.
See the standard for steel expansion bearing details to determine bearing plate a sizing steel girders or anchor plate sizing prestressed concrete girders. Load and resistance factor design lrfd for highway. Lrfd steel girder superstructure design example lrfd hipatia. This standard also gives an example of a temperature setting table for steel bearings when used for steel girders. Aashto lrfd us units 4th edition, including 2009 interims flared girder. Analysis and design of composite steelgirder bridge. This document consists of a comprehensive steel girder bridge design example, with instructional commentary based on the aashto lrfd bridge design specifications second edition, 1998, including interims for 1999 through 2002. Acecncdot spliced girder workshop rosebankpatiki interchange, nz built in 1997 2 435 ft spliced girder structures curved ramps with 492 ft radius 4 spans with 8 ft max. We wanted an interior structural steel girder to be placed within the plane of the precast slab units, thereby producing a thin floor construction akin to flatplate with a minimum floor to ceiling height. The steel girders have fy 50 ksi and all concrete has a 28day compressive strength of fc 4. Set minimum beam requirement for bridges with vehicular traffic 3.
In lrfd design, structural materials must be able to. Critical dimensions and loads are repeated here for ease of reference. Structures design office lrfd design examples files pdfs. Transient loads include live loads, wind, temperature, braking force and centrifugal force. Michael baker international for pennsylvania department of transportation.
Lrfd substructure example 2 2column pier on drilled shafts. Lrfd steel girder superstructure design example abutment and wingwall free download as pdf file. Design process flowcharts for superstructure and substructure designs. Superstructure general illustrates three load cases for exterior girder design with. Structural steel design, lrfd method manual of steel rar. The design process and corresponding calculations for steel i girders are the focus of this example. In addition, a design example for a twospan plate girder superstructure is included.
Wisdot bridge manual chapter 24 steel girder structures. The flange section is varied along the length of the bridge following the. The substructure has been analyzed in accordance with the aashto lrfd bridge design specifications, 4 th edition, 2007 and the 2008 interim revisions. The girder slab system and the open web dbeam girder technology are the result of more than fifteen years of research and development. Volume 4 provides detailed superstructure design examples which support the text in volumes 1 through 3. Design criteria neither the aashto lrfd specifications nor the aashtostandard specifications. Course examples will cover both lrfd and asd design prerequisites. May 18, 20 contentlrfd design example for steel girder superstructure bridge aashto lrfd design example horizontally curved steel box girder bridge horizontally.
Penndot dm4 design manual follows such a practice others have assigned. Uptodate coverage of bridge design and analysisrevised. Comprehensive design example for prestressed concrete psc girder superstructure bridge with commentary in us customary units this document consists of a comprehensive design example of a prestressed concrete girder bridge. As such adot has modified some lrfd deck design criteria to reflect past performance of decks in arizona. Abstract the purpose of this example is to illustrate the use of the aashto lrfd bridge design for the design of a continuous two span steel i girder bridge. There are two structural design methods namely asd allowable stress design method and lrfd load and resistance desig. Lrfd steel girder splice design and analysis splrfd version 1. Design of a rectangular beam posttensioned with straight cfrp cables example b5. The following design method can be used for normal weight concrete with specified compressive strengths up to 15. Lrfd substructure example 2 2column pier on drilled. The reaction from that lane is moved across the width. Design step 5 design of superstructure prestressed.
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