LOCAL BUCKLING BEHAVIORS OF COLD-FORMED CIRCULAR HOLLOW SECTIONS HIGH STRENGTH STEEL STUB COLUMNS BASED ON A HIGH-FIDELITY NUMERICAL MODEL (ICASS’2022)

This paper establishes a high-fidelity numerical model to systematically investigate the local buckling behaviors of cold-formed circular hollow section (CHS) high-strength steel stub columns. Material nonlinearity and geometric nonlinearity are carefully accounted for in the FE model. Based on the Menegotto-Point model, the material constitutive of cold-formed CHS is calibrated considering the characteristics of the curvature of the stress-strain curve. The mesh is uniformly patterned according to the cross-section of the CHSs steel under compression. Subsequently, parametric studies are carried out to study the local buckling mode, buckling strength and ductility of the cold-formed high-strength CHS. The cross-sectional slenderness limit and local buckling strength of CHSs with material strength more than 500 MPa are proposed.