Equivalent computational models and deflection calculation methods of box girders with corrugated steel webs

Abstract This study found that it is improper to use equivalent concrete webs (ECWs) to replace corrugated steel webs (CSWs) in the MIDAS Civil. To reflect the mechanical performance difference of CSWs in different directions, a more precise theoretical model, the assimilated orthotropic plate (AOP), is presented to simulate CSWs. 3D Finite element analysis demonstrates that the AOP model can yield a more precise description of CSWs compared with the ECW model in MIDAS. In addition, this paper presents a unified calculation method for bending deformation suitable for the analysis of beams with equal-area or variable-area cross-sections, in which the non-prismatic beam is made equivalent to the prismatic beam by introducing the concept of equivalent inertia moment. Additionally, the formula of shear deformation in a non-prismatic box girder with CSWs is also derived with Timoshenko beam theory. These derived formulas for non-prismatic box girder with CSWs agree well with the numerical and measured data.