Deformation of a Tapered Box Girder with Trapezoidal Corrugated Steel Webs Considering the Resal Effect: Theory, Experiments, and Numerical Simulations

Abstract

Due to the weakened shear stiffness of trapezoidal corrugated steel webs (TCSWs), it is necessary to account for shear deformation in calculating the total deformation for girders with TCSWs. Most of the existing research on the deformation of girders with TCSWs has mainly concentrated on prismatic cases. However, there has been a lack of research on the deformation analysis of tapered girders with TCSWs. Based on theoretical derivations, experiments, and finite-element (FE) simulations, this study investigated the deformation of a tapered box girder with TCSWs, taking into account the combined influences of shear deformation and the Resal effect. The study found that the contribution of shear deformation to total deformation in a cantilever tapered test girder with TCSWs is significant, representing 10.88% at the free end, increasing to 14.19% at the midspan, and reaching a substantial 35.31% near the fixed end. Furthermore, the study revealed that the bending moment can also induce additional shear deformation on both the TCSWs and the inclined concrete bottom slab due to the Resal effect. Importantly, the shear deformation induced by the bending moment accounts for a substantial proportion of the total shear deformation in sections that experience higher bending moments. Therefore, the basic assumption, which applies to prismatic girders, that the TCSWs solely bear all the shear forces and that shear deformation is entirely induced by shear force on the web, does not apply to tapered girders. Consequently, the study proposed a theoretical formula that considers the additional shear force on the bottom slab and TCSWs induced by the bending moment for predicting the deformation of tapered girders with TCSWs. This method yielded more accurate deformation predictions for tapered girders with TCSWs and can serve as a solid theoretical foundation for structural deformation analysis.