Experimental and theoretical study on the behavior of cold-formed stainless steel stub columns

This paper presents an experimental investigation on the behavior of cold-formed stainless steel stub columns under axial compression. Nineteen hollow section specimens of seven section types were tested. Geometric imperfections, material properties and full-range load-displacement curves were obtained. The test strengths were compared with the four design strengths, which are respectively calculated by using the American specification, the European specification, the design method proposed by Rasmussen in 2004, and the design method proposed by Gardner in 2008. The American specification, the European specification, and the design method proposed by Rasmussen are generally conservative. While the design method proposed by Gardner is relatively accurate. Based on the comparisons, modifications to Winter equation were derived to involve both the factors of the corner enhancement of the cold-formed members and the nonlinear property of stainless steel. The modified Winter equation can predict the strengths with low scatter.