Preventing cracking at diaphragmplate girder connections in. Design a welded plate girder of span 24 m to carry on superimposed load. Use is made of a computer program to compare the behaviour of alternative girder support systems and the advantages and disadvantages of each is summarized. It carries an uniformly distributed load of 100 knm. Use is made of a computer program to compare the behaviour of alternative girder support systems and the advantages and disadvantages of. Pdf this study concerns with finding the geometric dimensions of a plate girder. Characteristics design of gantry girder is a classic example of laterally unsupported beam. Welded plate girder stress mechanics continuum mechanics. The plates were joined together using angles and rivets to obtain plate girders of desired size. In a plate girder bridge, the plate girders are typically ibeams made up from separate structural steel plates rather than rolled as a single crosssection, which are welded or, in older bridges, bolted or riveted together to form the vertical web and horizontal flanges of the beam. The cracks are due to outofplane bending of the web near the top flange of the girder. Welded plate girders should be specified instead of rolled beams for the conditions as follows. Design to ec3 part 15 nanyang technological university. All the standard hotrolled shapes in the manual, the webs are compact.
For fillet welds, even though the joint may be required to carry wholly compressive stresses and the plate surfaces may be machined to fit, the total stress fluctuation. 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. In buildings, when large columnfree spaces are designed to be used as an assembly hall, for example, the plate girder is often the economical solution. Optimum design of welded steel plate girder using genetic algorithms. Design steps for plate girder design of steel structure ll. 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 igirder bridge. In india, industries usually have quality range of gantry girders for industrial sheds.
When the second girder line is set, the permanent diaphragms can be installed between girder line 1 and girder line 2. Design considerations for steel plate girder bridges. These steel structures design spreadsheet are easy to use, but powerful steel structural designing excel software to make things easy. Steel plate girder bridge design using indian standard. Plate girder design using lrfd university of maryland. To display the strand details inside the base file, open the reference file dialog box and activate the display option of the file with the description that. Welded plate girder, genetic algorithms, structural optimization, objective function, mutation, crossover. Most of the fatigue design recommendations are developed with the purpose of achieving a reliable design with respect to this failure mode. This document provides guidance to help steel bridge designers working on texas. The first task, analysis and design of horizontally curved plate girder and. Seshu adluri introduction steel connections many configurations are used for force transfer in connections. Make use of the detail at each and every available gusset plate. Assume case 1 follow procedure of design of plate girder.
Introduction 1optimization in the field of engineering not only aims at. The work oonsisted of analytioal studies and a series of tests on full size, welded steel girders. Structural pipe and tubing shall be galvanized inside and outside. The design may be based on any one of the following assumptions. Mar 22, 2018 design of plate girder part2 duration. Design of prestressed girder for bridge prestressed girder reinforcement details duration. 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. Plate girder literature af area of compression flange af as area of transverse stiffener as aw area of web aw a panel length measured from centerline to a centerline of transverse stiffener b width of comp. 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. You can do the hard part of steel calculation in minutes with the inputs. 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. However, it is a necessary and important part of plate girder design when applying the load and resistance factor design lrfd specification. For these beams, readymade i sections are not suitable since selection from design of steel structures book. Astm a709 grade 50, galvanized, or painted, shall be used in the design for trusses.
The cracks are due to out of plane bending of the web near the top flange of the girder. Plate girders are used in both buildings and bridges. Design of steel structures by limit state method as per is. Nowadays whole world is going for the limit state method which is more rational. View notes plate girder design process from cee 462 at university of illinois, urbana champaign. Zahn what differentiates a beam from a plate girder.
Plate girder bridges details and design requirements plate girders became popular in the late 1800s, when they were used in construction of railroad bridges. Design of welded connections american welding society. If rolled beams are specified, the selected sections shall be ensured to be available. Plate girder design using lrfd, engineering journal, american institute of steel construction, vol. Plate connections bolted flange plate welded unreinforced flangewelded web wufw kaiser bolted bracket conxl instructional material complementing. Plate girder article about plate girder by the free dictionary.
Structural steel 1 of 18 rev plate girder design project. Except for nu girders the standard drawings consists of one base file containing girder details used in most designs and one reference file containing strand details that vary by design. Plate connections bolted flange plate welded unreinforced flangewelded web wufw kaiser bolted bracket conxl instructional material complementing fema 1051, design examples steel structures 43. Cee462 steel structures ii summary of plate girder design process 1.
Bracing of welded igirder structural engineering general. Plate girders became popular in the late 1800s, when they were used in construction of railroad bridges. 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. The formulation is very general and includes a variety of design options such as. Seshu adluri plate girders deep girders three plates welded or bolted rolled sections not enough usually 320 deep wwf sections in the handbook can be used web buckling. Some of the iowa department of transportation iowa dot continuous, steel, welded plate girder bridges have developed web cracking in the negative moment regions at the diaphragm connection plates. Analysis and design of plate girder and box girder test. The first task, analysis and design of horizontally curved plate girder and box girder test assemblies, is complete. Welded plate girders can be designed as long and as deep as required by the design and fabrication method. The design shear forces and bending moments are shown in fig. Download free excel spreadsheet design for steel structures.
The minimum effective length of a fillet weld shall be at least four times the nominal size, or the effective size of the weld shall be considered not to exceed 25% of its effective length. Dec, 2012 plate girder for efficient design it is usual to choose a relatively deep girder, thus minimizing the required area of flanges for a given applied moment, msd. Lrfd steel girder superstructure design example lrfd. Welded bracket connection design as per is 8002007 lsm duration. In such cases, the designer must choose between a plate girder and a truss. If capacity of crane is moderate, the gantry girders rest on brackets connected to roof column of industrial shed. Pdf optimum design of welded steel plate girder using. The typical welded plate girder consists of flange plates welded to a deep web plate.
Plate girder for efficient design it is usual to choose a relatively deep girder, thus minimizing the required area of flanges for a given applied moment, msd. Covers current design techniques for both allowable stress and new load and resistance factor design lrfd approaches recommended by the forthcoming american association of state highway and transportation officials draft specifications. The configuration depends upon the type of connecting elements, nature and magnitude of the forces and moments, available equipment, fabrication and erection considerations, cost, etc. Design a welded plate girder 24 m in effective span and simply supported at ends. Stiffened plate girders may or may not be designed for tensionfield action to.
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 designanalysis program no. 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. Structural steel design, fabrication, and construction. The design process and corresponding calculations for steel igirders are the focus of this example, with particular emphasis placed on illustration of the optional moment redistribution procedures. As such, it is capable of supporting greater loads on longer spans. This module addresses the design of welded plate girders. Plate girder design using lrfd american institute of steel. Rail height mm effective length factor typical span crane step size m dead load factor live load factor combined load factor. Assisted by skilled workers in india, companies have been able to successfully grow towards the zenith, but. Cl stress modification coerficient depending on 01.
Adobe reader software is used to view the codes in soft copy format to ease the. This document is disseminated under the sponsorship of the u. Preferred practices for steel bridge design, fabrication, and erection. Pdf design of plate girders miftakhu zaim academia. Pdf the design of structures whether reinforced concrete or steel are governed by code provisions. Welded plate girders, which are the most common form of plate girders, are builtup.
The recommended spandepth ratio for simply supported girder varies between 12 for short span and 20 for long span girder. Prestressed concrete igirder psi missouri department of. Welded plate girders, which are the most common form of plate girders, are built up. 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. Plate girder design process cee462 steel structures ii. If you would be more comfortable using both pipe braces, it wont hurt but i dont consider it necessary. Always provide enough access for bolting, welding, and painting. So far working stress method was used for the design of steel structures.
Lrfd design example for steel girder superstructure bridge. If main primary members are weathering steel, secondary members shall also be weathering steel. Each document represents the consensus of a diverse group of professionals. A practical approach to design for efficient fabrication and construction. In rare instances integral pier caps or substructures will be designed using steel. Optimum design of welded steel plate girder using genetic. For this steel girder design example, a plate girder will be designed for an hl93 live load. By 1950s welded plate girders replaced riveted and bolted plate girders in developed world due to their better quality, aesthetics and economy. Thus, use of a hybrid girder requires an approved design waiver.