Tensión crítica de abolladura a cortante de almas esbeltas de vigas metálicas de inercia variable

Critical shear buckling stress of slender tapared web panels

In certain design situations of steel structures (steel building frames, and steel and composite bridges), the hot - rolled section beams (I and H) have not sufficient strength to resist the stresses that will be developed in the elements of the structure. By using tailored plate girders, which are usually made of several welded or bolted plates, this problem is solved. 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, the depth of which varies as bending moment varies. These members will reduce not only the amount of material, but also the self - weight of the structure. Usually, the depth of the web plate varies linearly. One of the main distinctive features in the structural behaviour 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 paper presents an analytical formulation that makes it possible to determine the critical shear buckling stress of slender tapered web panels, which have an aspect ratio a, equal to unity. This formulation, obtained on the basis of numerical studies of plate instability, takes into account the influence of the boundary conditions of the tapered web.