Simulation and analysis of composite girders with corrugated steel webs using spatial grid model

Composite girders with corrugated steel webs (CSWs) represent a highly promising structure type worldwide. This paper proposed a novel finite element (FE) model named the spatial grillage model (SGM) to simulate and analyze composite girders with CSWs, which balances simplicity and accuracy. Firstly, the mechanical behavior and orthogonal stiffness of CSWs were examined, followed by the simulation methodology by the cruciform grids. Subsequently, the spatial grillage model (SGM) was established, wherein concrete flanges were modeled as conventional individual girders or planar grillages according to their widths and then connected to the cruciform grids of CSWs by rigid arms. The feasibility of the proposed model was demonstrated by a thorough comparison with ANSYS solid/shell models. The results show that the proposed model achieves high accuracy in static, modal, and global buckling analyses with a greatly reduced number of elements. Regarding the buckling at the component level, particularly concerning the local buckling of CSWs, the proposed model demonstrates conservative predictions for the buckling load factor, necessitating the integration of critical shear stress criteria to achieve more precise control. In the end, the engineering application prospects were discussed and conclusions were drawn.