Compound flexural-torsional capacity of composite girders with corrugated steel webs and CFST truss chords: a calculation method

Abstract

Based on the compound flexural-torsional mechanical mechanism and with due consideration of the coupling effect between torque and bending moment, a calculation method for the compound flexural-torsional bearing capacity of composite girders with corrugated steel webs and concrete-filled steel tubular (CSW-CFST) truss chords is derived and proposed. The reliability and applicability of the proposed method are validated against a comparative database consisting of existing experimental results and numerical analysis outcomes. The numerical analyses agree well with the experimental data, exhibiting consistent trends. This confirms the accuracy of the numerical method in realistically capturing the stiffness evolution and mechanical performance progression of CSW-CFST truss chord composite girders under combined flexural-torsional loading. Compared with the existing calculation methods for compound flexural-torsional bearing capacity of composite girders, the proposed method reduces the prediction deviation from 22.3 % to 9.1 % when evaluating the compound flexural-torsional bearing capacity of CSW-CFST truss chord composite girders. Furthermore, the proposed method is also shown to be applicable to composite girders with varying cross-sectional configurations.