The bottom triangular cell: A significant improvement for patch loading resistance in launched bridges

Abstract

This paper deals with the improvement in patch loading resistance achieved by a bottom triangular cell attached to a T-shaped girder flange. The analyses performed with hybrid non-linear finite element models reveal two resistant mechanisms: web resistance and an additional contribution of vertical stiffeners induced by the bottom cell stiffness. A numerical model is proposed for evaluating the contribution of vertical stiffeners to patch loading resistance, in order to improve present formulation deficiency. The conclusions are applied to a real case design of a launched bridge, the viaduct across river Sava in Croatia, eliminating all longitudinal web stiffeners.