Web buckling of tapered plate girders

Abstract

When hot rolled beams (cross-section I and H) show insufficient strength or are not economic for design purposes, plate girders are usually designed, in most cases by welding several plates together. More efficient structural elements can often be achieved by designing these plate girders as tapered plate girders. This is usually done by means of a web panel (steel building frames, and steel and composite bridges), the depth of which varies linearly. One of the main distinctive features of tapered plate girders is the considerable slenderness of the web. This often results in web buckling in the elastic range prior to the yielding of the steel. This article presents an analytical formulation that makes it possible to determine the critical shear buckling stress of slender tapered web panels. This formulation, obtained on the basis of numerical studies of plate instability, takes into account the influence of all the geometric design parameters and the presence of the flanges.