Shear Behavior of Corrugated Web Bridge Girders

Results from many shear strength tests conducted on steel I-girder specimens with corrugated webs are available in the literature wherein both local and global shear buckling modes have been observed. A systematic analysis of these data has revealed that previously proposed equations based on plate buckling theories can overestimate the shear strength of corrugated webs by a considerable margin. The results of finite element analyses conducted as part of this investigation suggest that the strength is overestimated, at least in part, because of the sensitivity of the shear behavior to the presence of initial imperfections in the web. Shear tests reported in the literature were conducted primarily on relatively small-scale specimens with dimensions and web thicknesses substantially smaller than would be used in actual bridge girders. Therefore, two full-scale corrugated web girders made of HPS 485W steel were tested. The shear strength and failure mode of the girders are reported and the effect of web initial geometric imperfections is assessed through measurements of the out-of-plane displacements of the web. Since web imperfections due to the fabrication process, as well as residual stresses and material nonlinearities, are expected to be present in varying degrees, a lower bound equation is proposed for design that accounts for both local and global buckling of the web in the elastic and inelastic domains.