Flexural buckling behavior of welded stainless steel box-section columns

•Experimental study on flexural buckling of welded austenitic and duplex stainless steel box-section columns was presented.•The residual stress and geometric imperfection measurements were conducted.•Finite element analysis was conducted to supply the experimental outcomes.•The comparison of bearing resistance and column curves between the test and EN 1993-1-4, ASCE and AS/NZS was illustrated.

Flexural buckling behavior of stainless steel columns has been widely investigated and discussed. However, a barely explored area is that of welded-section members. In this paper, twelve full-scale columns buckling tests have been conducted for both austenitic and duplex welded stainless steel box-section members. Specimen cross-sections and lengths have been selected to cover a wide range of geometries, varying between non-dimensional slenderness of 0.5 and 2.0. Measurements of material properties, residual stress and initial geometric imperfection have been also conducted. Relevant numerical simulation has been performed, accuracy of which is verified by comparing with the test results. The test results have been used to assess the applicability of the EN 1993-1-4, ASCE 8-02 and AS/NZS for stainless steel welded-sections. It shows that current design method predicts the buckling resistance of welded stainless steel box-section generally conservative thus improvement could be anticipated.