Date of Publication :25th January 2018
Abstract: The plate girder is fabricated from plates and the designer has greater freedom to vary the section to correspond with changes in the applied forces. Thus variable depth plate girders have been increasingly designed in recent years. For a given bending moment the required flange areas can be reduced by increasing the distance between them.Thus for an economical design, it is advantageous to increase the distance between flanges. To keep the self-weight of the girder as the minimum, the web thickness should be reduced as the depth increases, but this leads to web buckling. Web buckling considerations being more significant in plate girders than in rolled beams since Rolled beam section are manufactured by keeping depth to thickness ration such that there will be no local bucking in the web. The web buckling of plate girder can be avoided by using the thicker web or by using stiffeners.In this paper feasibility of using stiffeners to reduce the dead load, material and fabrication cost of plate girders is studied. Use of transverse stiffeners lead to creating tension field in the plate girders prior to buckling and this tension field helps to increases the buckling resistance of web. In this paper as per IS: 800:2007 design of plate girder is done. The optimum section for the given load is found out by varying the thickness of web and number of stiffeners in different trials. Finally, the most suitable section for a given load is proposed in this paper
Reference :
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- IS : 800 : 2007, Indian standard general construction in steel-code of practices.
- Basler.K (1961), Strength of plate girders in shear. ASCE 128 (2) (1961).
- Rahal.K.N,(2010) “Transversely Stiffened Girder Webs Subjected to Shear Loading“ Part. 1:Design,Proceedings of In situation of Civil Engineers,Part2, 1989,pp.67–87. Alinia M.M .(2003) “Shear failure characteristics of steel plate girders”. Thin-Walled Structure 2009;47:1498–50