Design of simply supported hot-rolled steelshort-to-intermediate angle columns - Design approach based on the direct strength method (DSM)

Selected, extended paper from the SDSS 2019 special session ECCS/TC8 - Structural Stability
This work reports on the results of an ongoing investigation of the direct strength method (DSM) design of hot-rolled steel equal-leg angle columns with pinned (spherically hinged) supports and short-to-intermediate lengths, i.e. buckling in flexural-torsional modes. It extends the scope of similar studies involving cold-formed steel angle columns with the same characteristics (but higher leg width-to-thickness ratios). After collecting the experimental and numerical failure loads available in the literature concerning columns with several geometries, the paper addresses the mechanical reasoning behind a DSM-based design approach proposed in the context of fixed-end and cylindrically hinged cold-formed and hot-rolled steel short-to-intermediate angle columns, which must be modified to handle spherically hinged supports. After that, the failure loads gathered are used to assess the quality of their estimates using this design approach, namely, by determining LRFD resistance factors. It is shown that this approach can be successfully applied to predict hot-rolled steel simply supported angle column failure loads, leading to LRFD resistance factors above 0.90.