Behavior of large-size and high-strength angle steel built-up cruciform member under axial compression

Abstract The axial compression stability performance of large-size and high-strength angle steel (LHS) built-up cruciform members is investigated due to the current code’s conservative calculation and lack of specific design provisions regarding the bearing capacity. The finite element models of LHS built-up members with different geometric and mechanical parameters are established and verified. The comprehensive parametric study was adopted to perform LHS built-up members with various sections, filler thickness, slenderness ratio, filler plate spacing, and strength grade. Numerical results obtained from the parametric study were compared with the current design codes to provide more accurate predictions of design strengths. The research findings indicate that the constraint effect brought about by increasing filler plate thickness has a limited effect on improving the built-up members’ bearing capacity. The column curve in the existing specifications exhibits varying degrees of error in different slenderness ratio ranges. The proposed modified design equation for LHS built-up members can achieve reliable and accurate design predictions with different strength grades.