General method for I-section stainless steel beam-columns

A significant progress in the development of stainless steel design procedures which were implemented also in new design standards proposals, prEN 1993-1-4:2021 and AISI 370-21, has been going on in the last 15 years. For compressed members, buckling curves were revised and beam-column interaction formulas were published for hollow and open sections. Buckling curve was significantly improved for double-symmetrical I section beams. The Continuous Strength Method was introduced in the code. Also, a verification procedure using a plastic global analysis was developed and implemented in design procedures very recently. However, clear design rules for geometrically non-linear analysis with equivalent member and structural imperfections need further research. This approach, known also as the general method, became a very popular method for carbon steel structures, but cannot be used for slender stainless steel structures without modification. The stainless steel nonlinear stress strain diagram leads to a reduction of the bending stiffness and thus higher second-order effect, which needs to be covered in the procedure. In this research, a comparison is made on numerical parametric studies. Limits will be set for the applicability of the carbon steel design procedures and a preliminary recommendation for general method of stainless steel members will be presented. © 2023 The Authors. Published by Ernst & Sohn GmbH.