Design of SupaCee sections subject to web crippling under one-flange load cases

Cold-formed steel sections are generally used as flexural members in lightweight steel construction. The SupaCee section is an innovative section introduced recently to the Australian building sector. It provides superior flexural strength than the traditional channel sections due to unique ribbed web and curved lip elements. However, the web crippling behavior and strength of the high strength SupaCee sections has not been investigated yet. Current web crippling design methods given in cold-formed steel design standards do not include any provision for SupaCee sections. Hence, detailed experimental and finite element studies were conducted to investigate the web crippling behavior and strengths of SupaCee sections under one-flange load cases with their flanges unfastened from the supports. Experimental and finite element analysis results showed that the web crippling capacities of SupaCee sections are reduced relative to lipped channel sections. Therefore, the current web crippling design equations in the American and Australian/New Zealand cold-formed steel design standards were modified by including suitable web crippling coefficients for SupaCee sections. Finite element models of tested SupaCee sections were also developed and validated using the experimental results. This paper presents the details of experimental and numerical web crippling studies of SupaCee sections under one-flange load cases and the results. It also presents the details of direct strength method-based design equations developed in this research.