Experimental evaluation of DSM beam–column strength of cold-formed steel members under uniaxial eccentric compression

Abstract

In this paper, the direct strength method (DSM) design of cold-formed steel (CFS) beam–column is evaluated using the results of controlled experiments. The experimental setup is devised to create a uniform moment along the member length about both the major and the minor axes of the member. A comparison of code provisions of AISI S100-2016 for CFS beam–column design against twenty-two experiments reveals a disagreement when the failure mode is due to an interaction of distortional–flexural torsional (D+FTB) buckling. The study proposes a modification to the linear interaction framework (LI) and nonlinear interaction (NLI) framework to include the distortional–global (D–G) interaction. These modifications have been demonstrated to result in strength predictions that are closer to the experimental evidence.