Design of cold-formed steel columns subject to local buckling at elevated temperatures

Cold-formed steel (CFS) is one of the popular materials in low and mid-rise building construction. However, CFS member capacities reduce at elevated temperatures as their yield strength Young's modulus decrease with increasing temperature. In addition, exhibits nonlinear stress-strain characteristics temperatures, which significantly different to ambient temperature characteristics. Although several studies have been conducted on local buckling columns, they not considered effects such nonlinearity between proportional limit stress strength, varying yield-strength ratio strain hardening ultimate strengths. Thus, this research study investigated detail, proposed modified design equations for columns based effective width direct methods given AS/NZS 4600, since current give unsafe predictions many cases. The incorporating were developed using obtained from 740 finite element models lipped channel sections. A simplified method determine compression commonly used Australian open sections temperatures. • Investigated columns. Simulated by three parameters capacity evaluated. Conducted a numerical parametric idealised measured curves. Compared analysis results EWM DSM 4600. Proposed 4600 design.