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

• Published in: Thin-walled structures 2022-05, Vol.174, p.109096, Article 109096
• Main Authors: Rajkannu, J. Sevugan, Jayachandran, S. Arul
• Format: Article
• Language: English
• Subjects: Beam–column; Direct strength method (DSM); Distortional–global interaction; Linear interaction; Non-linear interaction
• ISSN: 0263-8231; 1879-3223
• DOI: 10.1016/j.tws.2022.109096

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. •Experimental setup for applying Beam–column action on lipped channel section with spherical end support.•Beam–column behavior of lipped channel sections under uniform Major axis moment and Minor axis moment.•Behavior of Distortional and interaction of distortion-global mode under beam–column action.•Implications of nonlinear interaction (NLI) design framework over linear interaction for DSM beam–column design.•Proposed possible modification to incorporate the Distortional–Global (D–G) interaction in the DSM beam–column design framework.