Optimization of compressed stiffened flanges in bridge box girder cross section

Abstract

Due to bending, flanges of steel box girder cross sections act as compression plates and require stiffeners. Using stability evidence from EN 1993-1-5, a parametric study was performed for six different types of stiffeners. The obtained diagrams show design buckling resistance stress for various plate width and thickness values, and the type and number of stiffeners. Furthermore, an optimization process was performed to find the most suitable types and number of stiffeners, depending on the acting design compression force. Optimization parameters are the minimum steel area and minimum number of stiffeners.