Postbuckling behavior and failure prediction of large‐size composite C‐beam under bending‐shear coupling load

Abstract In this article, a novel experimental device that combines bending and shearing was proposed to investigate the load‐bearing performance of large‐size C‐beam structures against bending‐shear buckling, allowing for the adjustment of bending‐shearing ratio. Three different bending‐shear coupling conditions were performed for test loading, and the strain gauges were carried out to detect the strain distribution for postbuckling performance of the large‐size C‐beam. The finite element models were established by ABAQUS/Explicit to explore the stress distribution and damage evolution during postbuckling failure. Thereafter, the LaRC05 and Hashin criterion was used for failure prediction of the large‐size C‐beam in numerical simulations. The experiment results show that the large‐size C‐beam has excellent postbuckling bearing capacity regardless of bending or shear resistance. Based on the results, the failure numerical model considering the stress distribution in postbuckling and the finite element calculation were in good agreement with experiments. This study can offer a practical reference for the postbuckling performance of large‐size C‐beam structures after bending‐shear coupling.