Stress Concentration Due to Shear Lag Effect in Simply Supported Steel Box Girders with Longitudinal Stiffeners

Abstract

The objectives of this research is to study about the shear lag effect and focus on stress concentration for steel box girder with longitudinal stiffeners. All of models in this research used the finite element method for studying the shear lag effect and the finite element mesh must be made with carefulness to assess stress concentration. The study examines the stress concentration in a flange due to the shear lag in a simply supported steel box girder by the three-dimensional finite element method using shell elements under two loading conditions of uniformly distributed load along girder length and concentrated load. Definitely, parametric study with respect to the geometry of steel box girder is used. The dependency of finite element mesh is carefully emphasized. It is also reported that the stress distributions in the flange are different from those of the elementary theory. Based on the results, empirical formulas are proposed to calculate stress concentration factors due to the shear lag effect.