ANALYSIS OF DEFORMATION-INDUCED FATIGUE OF THIN-WALLED PLATE GIRDER IN SHEAR

When a thin-walled plate girder is subjected to repeated shear, it is possible that fatigue cracks may be initiated along the web boundaries in regions where the tension field is anchored. They are caused by the secondary bending stress which is produced by out-of-plane deformation of the web. In this paper, first, the out-of-plane deformation and the secondary bending stress of a rectangular plate under in-plane shear are examined by the finite element analysis. Secondly, using the relation between in-plane shear stress and secondary bending stress, the fatigue strength is expressed in terms of the in-plane shear stress as a function of the web slenderness ratio. And the influence of various factors on the fatigue strength is discussed.