Accuracy of Buckling Strength Curves Using Direct Strength Method in Estimating Axial Strengths of Cold-Formed Steel Members under Compression: Critical Review.

Current design specifications for cold-formed steel incorporate the Direct Strength Method (DSM) to design cold-formed steel members under compression. Although the DSM has been used for quite some time, its buckling strength curves have not been experimentally assessed thoroughly. This study attempts to fulfill this objective. First, a thorough literature review was conducted to inspect the buckling strength curves in the DSM, and the issues are summarized in this paper. Second, experimental data associated with compression tests of 453 solid and 228 perforated cold-formed steel columns were collected from the literature. Design parameters (e.g., elastic critical buckling loads) of the columns were then determined and assembled with the experimental results in a database to be used as a source to assess the buckling strength curves in the DSM. Finally, the LRFD resistance factors (ϕc) of the DSM buckling strength curves were determined in accordance with the AISI S100. This paper highlights the level of accuracy of the buckling strength curves in the DSM. [ABSTRACT FROM AUTHOR]