The design examples provide coverage of all applicable limit states, whether or not a particular limit state controls the design of the member or connection. A plate girder cross section can take several forms. Key words steel bridge, steel i girder, aashto lrfd, moment redistribution, cross frame design 18. Department of transportation in the interest of information. Analysis and design of composite steelgirder bridge. Permanent steel deck forms are assumed between the girders. Steel plate girder bridge design using indian standard.
This type of bridge provides benefits of rapid construction, and improved structural performance. 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 recommended reading. In addition to the examples that demonstrate the use of the aisc manual tables, design examples are provided for. The examples cover the principal steps in the verification of the. This has led to increases in top flange size or the provision of plan bracing just for the erection condition where previously neither modification to the permanent design was likely to be needed. Design considerations for steel plate girder bridges. Pgsuper is a computer program for the design, analysis, and load rating of precast, prestressed concrete girder. A beginners guide to simple plate girder design to ec3 part 15. Contentlrfd design example for steel girder superstructure bridge aashtolrfd design example horizontally curved steel box girder bridge horizontally. Plate girder bridges details and design requirements plate girders became popular in the late 1800s, when they were used in construction of railroad bridges. The design example includes detailed design computations for the following bridge features. Calculates noncomposite and composite for modular ratios n and 3n section properties for steel igirders with concrete deck. The plates were joined together using angles and rivets to obtain plate girders of desired size.
Mar 11, 2016 history and background of plate girders plate girders became popular in the late 1800s, when they were used in construction of railroad bridges. The contract documents should state the fit condition for which the. With these tables, it 1s a simple matter to find the allowable shear stress for a given girder geometry, or. Many numerical examples have been considered to well understand the optimum design of plate girder. Simple span plate girder example aashtoware bridge.
Examples to eurocode steel design to en 1993 bs en page. The example bridge has four plate girders spaced at. The flange section is varied along the length of the bridge following. This document is disseminated under the sponsorship of the u. The span is 36 m and carries two concentrated loads as shown in fig. Determine the design flexural strength i b m n of the following welded ishaped plate girder. Design a typical floor joist university of alabama. Stiffener prevents buckling two methods of design of plate girders. Analysis and design of plate girder and box girder test. Aashto design specification lrfd bds section 6 8thed. The first example is of multi girder form, the second is of ladderdeck form. Assume case 1 follow procedure of design of plate girder. For curved girders, flange width no less than 25% of the web depth for straight girders, flange width no less than 20% of the web depth. Threespan continuous straight composite i girder load and resistance factor design third edition customary u.
The steel girder design criteria are obtained from figures 31 through 33 shown below, from the concrete deck design example, and from the referenced articles and tables in the aashto lrfd bridge design specifications through 2002 interims. Structural steel 1 of 18 rev plate girder design project. The design criteria is to strengthen the girder to obtain a. Lrfd design example for steel girder superstructure bridge us. A plate girder with fe415 plates is having 12mmx150mm web plate and 56mm x 500mm flange plates. Each tutorial includes module files and step by step guidelines so you can improve your midas civil skills via completing a small project. Pdf design of plate girders miftakhu zaim academia. The companion consists of design examples in parts i, ii and iii. Ce 331, spring 2002 joist and frame design example 1 2 1. An example of application shows a good agreement with the developed formula. Plate girder shear and flexural strengthening design example design procedure the following american association of state highway and transportation officials aashto documents were used for this example. Girder analysis and design is performed using the computer. Review this document when initiating a steel bridge design. The research was performed to develop guidelines for design and construction and to address issues that significantly influence performance.
Zahn what differentiates a beam from a plate girder. Design steps for plate girder design of steel structure ll duration. Allow girder end rotation avoid thick cap plates place the bolts outside of the column flanges. Transverse web stiffeners and shear moment 017 interaction. Steel tutorial aashtoware bridge design and rating products.
For an efficient design, any calculation relating to the ultimate limit state should take the postbuckling action into account. The primary goal of the collaboration is to achieve steel bridge design and construction of the highest quality and value through standardization of the design, fabrication, and erection processes. For example, the development of postbuckling action in a web plate, assumed in the previous lectures, can only occur when the elements at. The typical welded plate girder consists of flange plates welded to a deep web plate. Structural steel design, fabrication, and construction. O ten steel plate girder bridges were monitored o seven simple span o two twospan continuous o one threespan continuous o girder deflections were measured in the field during the concrete deck placement o developed 3dimensional finite element models to simulate deflections measured in the field. This bridge is the igirder design example presented in the appendix of the aashto guide specifications for horizontally curved steel girder highway bridges, 2003. This design example, plate girder shear and flexural strengthening i,nvolves the addition of steel strenghening material to an existing steel plate girder. As such, it is capable of supporting greater loads on longer spans. Customized solutions book is provided pdf standard design and details of short span steel bridges solutions rolled beam recommendations plate girder recommendations standard design and details of corrugated steel pipe and structural plate solutions manufacturers steel. Design to ec3 part 15 nanyang technological university. Aas hto m2 7 0, g ra d e 5 0 w u n c o a te d we a th e rin g s te e l with f y 5 0 ks i.
Structural steel design, fabrication, and construction jamie f. Difference between beam and girder with 3d animation duration. Torsional bracing of beams brace stiffness and strength requirements 6 aisc specification appendix 6 bracing provisions. By 1950s welded plate girders replaced riveted and bolted plate girders. Do not use knee braces allow for adjustment in placing the crane girder.
Pdf this study concerns with finding the geometric dimensions of a plate girder. Enter the impact to be used for the entire bridge by clicking on impact in the tree and selecting fileopen from the menu. Diaphragms crossframes throughgirders the beam or girder is fully braced at a location if twist is prevented. 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. Shape sections, other than pipe and tubing, are typically available in 36, 50, or 50w grades. Comparing bs5950 with ec3 part 15 in plate girder design design of plate girder bs5950 most design rules found in sections 4.
Expand the stiffener definitions tree item and double click on transverse. Use a36 steel and assume the girder has continuous. The first task, analysis and design of horizontally curved plate girder and box girder test assemblies, is complete. The example illustrates the design of a typical threespan continuous straight steel igirder bridge with spans of 140. The following note discusses the standard formula for the shear flow between web and flanges of a doubly symmetric beam which is used for weld design and gives the background to the formula in eurocode 3 part 51. Reference collaboration constructability document to evaluate introduction of shop splices two or fewer in. For curved girders, use above and increase by 10 to 20 percent, or use lrfd equation 2. Lateral buckling of steel plate girders for bridges 022. Acknowledgements brian merrill, txdot brg john holt, txdot brg. 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. Neglecting the thickness of the flange in calculating the shear flow is clearly conservative. Crotch plate design for outlets and true wyes, 109 crotch plate design, 109 nomograph use in radial outlet and wyebranch design, 110 crotch plate connections, 114 true wye design, 122 design of ellipsoidal heads, 125 testing of fittings, 126 joint harnesses, 126 anchor rings, 143 anchor ring design, 149 outlets, 155 blowoff connections, 155. It gives two worked examples, one for a multi girder bridge and one for a. Curved steel 3d example aashtoware bridge design and rating.
Plate girder worked example 1 made by sssr date 150400 structural steel design project calculation sheet checked by pu date 250400 problem. Pdf the behaviour of plate girders under in plane loading has. This book addresses the entire design process for a steel tub girder bridge and offers a list of pertinent references for each phase, including suggestions on how to find some hardtolocate documents. For example, the development of postbuckling action in a web plate, assumed in the previous lectures, can only occur when the elements at the boundary of that web plate are able to provide an adequate anchorage for the. A sample input file and selected excerpts from the corresponding output file are. The design may be based on any one of the following assumptions. Steel plate girder deflections a look at the development and. Repeat this process to define the other two stiffeners. Plate girder design using lrfd university of maryland. E1 is fully restrained against lateral buckling throughout its span. One diagonal is in tension and one is in compression. Although there are preliminary steps, lrfd specification appendix g2 gives the flexural capacity for a plate girder, whereas appendix f1. O ncsu research on dead load deflection for steel girders o design examples.
Design considerations for steel plate girder bridges the texas. This design example was edited in 2012 by hdr engineering, inc. Some authors examined the behavior and design of plate girder and also, many. This study concerns with finding the geometric dimensions of a plate girder which minimize the total weight and satisfy the design requirements using genetic algorithm ga, sequential quadratic. Girders also rotated and tilted in this cambered state 57 girder web centerline tilted 1. Section properties section properties are per foot of width. Plate girder shear and flexural strengthening design example. A steel plate girder should be designed to optimize weight savings in correlation with fabrication and erection costs.
Introduction to the design of wood trusses by derek l. Steel plate is available in 36, 50, and 50w grades. The example illustrates the design of a typical threespan continuous straight steel i girder bridge with spans of 140. Steel girder design example using 3rd edition aashto lrfd. Calculates cumulative stresses at critical locations for loads applied to noncomposite and composite sections. The following american association of state highway and transportation officials. Note that a direct comparison should not be made between the unit weight of the example design contained herein and the unit weight of the design given in example 3 of the aisinsba publication entitled four lrfd design examples of steel highway bridges. If capacity of crane is moderate, the gantry girders rest on brackets connected to roof column of industrial shed. A beam built up of steel plates and shapes which may be welded or bolted together to form a deep beam larger than can be produced by a rolling mill see illustration. This lecture seeks to complete the discussion of plate girder design by considering further aspects of detailed design. Additionally, the weld design for the webtoflange joint of the plate girders is demonstrated along with all applicable components of the stiffener design and cross frame member design. A 10m span plate girder 600 mm deep by 300 mm wide with 30 mm thick flanges and a 10 mm thick web steel grade s355 carries a central point load of 800 kn.
Plate girders be made shallcomposite with the bridge deck be and should continuous over interior supports where applicable. The superstructure design includes the following elements. Structural steel of primary members shall satisfy the toughness requirements for zone 3. Provides guidance for plate girders, rolled beams and tub girders. For e, this difficulty is overcome by tabulating allowable stresses for different materials astm a7 a36, etc. The girder is to be strengthened due to section loss from corrosion. Tmcp hps is available in plate thicknesses up to 2 inches and in.
The purpose of the plate girder is to build a beam that is larger than anything that can be built by a steel mill or factory. Continental steel public seminar, 6 august 2014, ntu design of plate girder design of plate girder shear resistance if the web is stocky, no shear buckling of web shall occur and the shear strength of the web is given by ec3 part 11 if the web is not stocky, shear buckling governs the failure. The purpose of this document is to illustrate how the pgsuper computer program performs its computations. Plate girder bridges details and design requirements. Curved plate girder design for safe and economical construction justify recommendations in preferred. Accessories ridge and valley cover plates and flat plates at change of deck direction when attached directly to the steel deck and as shown on contract documents, shall be furnished by cmc joist and deck. The subscripts p and n refer to positive and negative bending. Lrfd design example for steel girder superstructure bridge. University of kansas march 1, 2018 engineering conference crane girder design.
This project includes a detailed outline and a series of flowcharts that serve as the basis for the design example. The existing bridge was designed for hs20 live loading. A plate girder is subjected to a maximum factored moment of 4000 knm and factored shear force of 600 kn. Formula 5 may seem too complicated for design purposes. Steel truss plate girders two or more regular beams types of plate girders innovative use of material in plate girder components of a plate girder. This report documents part of the results of a study of decked, precast, prestressed, concrete bridge girders. Design example, 180 ring girders, 183 ring girder construction for lowpressure pipe, 183.
The tributary area for a girder truss is half the sum of all the tributary areas of the supported trusses plus half the area to the next truss. Plate girder article about plate girder by the free dictionary. For this steel girder design example, a plate girder will be designed for an hl93 live load. Overall presentation outline introduction analysis topics. The torsional deformation of the girders either from buckling or torsional moments result in the following deformation. Crane girder design 5 crane column cap plates allow girder end rotation avoid thick cap plates place the bolts outside of the column flanges.
Example front diaphragm has been both tilted and rotated in order to match hole patterns with web stiffeners. Design a typical floor joist for the two story office building indicated below. Precast, prestressed girder design example pgsuper training 242020 1. The first example is of multigirder form, the second is of ladderdeck form. 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. However, it is a necessary and important part of plate girder design when applying the load. This publication presents worked examples of the detailed design of two composite highway bridges. Depending on our design assumptions, we can idealize the cross frame in a. Hypothetical design calculations for shear force capacity. Design verifications for simple steel plate girder bridges, consider spot checking computer program design and analysis output by rough hand calculations if practical for complicated steel plate girder bridges curved, consider verifying design with a second design analysis program no two programs will match exactly of course. You can easily design any plate girder on the basis of these steps with a simple process of design by following our given steps in the pdf file provided below.
Each bridge is formed by steel girders acting compositely with a reinforced concrete deck slab. Characteristics design of gantry girder is a classic example of laterally unsupported beam. The design process and corresponding calculations for steel i girders are the focus of this example, with particular emphasis placed on illustration of the optional moment redistribution procedures. Gusset plates and splice plates in trusses, arch ribs, tie girders, and rigid frames primary splice plates and cover plates in. Homogeneous and hybrid plate girders with limited plate. Siteblauvelt engineers cranberry township, pa pittsburgh, pa b s d i design.
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