Shear stress analysis of tapered box girders with CSWs under eccentric load

Existing research on the shear behavior of box girders with corrugated steel webs (BGCSWs) under eccentric load has predominantly focused on prismatic members. This study, for the first time, identifies significant differences between the shear behaviors of prismatic and tapered BGCSWs under eccentric load. Specifically, the Resal effect induces additional shear stresses in the corrugated steel webs (CSWs) due to the bending moments generated by eccentric loads—an effect that is not currently addressed in existing design codes or calculation methods. To this end, a novel theoretical model is proposed for evaluating the shear stress in tapered BGCSWs subjected to eccentric load. This model integrates shear forces, torsional and distortional effects, as well as the additional shear stresses induced by bending moments. Experimental investigations and finite element (FE) simulations validate the proposed model, demonstrating its high computational accuracy. Compared to conventional methods, the proposed approach offers more precise predictions of the shear stress in tapered BGCSWs under eccentric load, while conventional methods may underestimate the shear stress in the CSWs. Additionally, this study introduces shear stress amplification factors, elucidating the relative contributions of shear force, bending moment, torsional, and distortional effects to the overall shear stress, thereby providing valuable insights for the design of tapered BGCSWs.