Momententragfähigkeit schlanker Biegeträger - Einfluss des flanschinduzierten Stegblechbeulens

For plate girders in bending with very slender webs the curvature due to bending along with the axial forces of the flanges generate transverse compression forces in the web, that are likely to produce web buckling. The current version of Eurocode gives a limit value for the web slenderness ratio hw/tw in order to avoid this phenomenon of flange induced buckling. Higher slenderness ratios are not within the scope of the code. For smaller slenderness ratios no interaction between buckling due to axial forces and transversal forces is considered.

Subsequently, after a short introduction on the limit slenderness ratio, the moment capacity of I shaped girders is systematically analysed as a function of the web slenderness ratio hw/tw – even for ratios higher than the limit value. The numerically determined moment capacities are then compared with the design criteria of Eurocode (i. e. effective widths method and reduced stress method).