Numerical study and design of S35657 stainless steel welded stub columns

As a new type of austenitic stainless steel with high nitrogen and low nickel, S35657 stainless steel has the characteristics of high strength and low price, and it has a good application prospect in the field of construction. To supplement the relevant research on S35657 stainless steel structures and to evaluate the applicability of existing specifications and design methods, a finite element model was established using ABAQUS software and calibrated using existing test results. Furthermore, a series of parametric analyses were carried out, focusing on the effects of width-to-thickness ratio, initial geometric imperfection, and welding residual stress on the local buckling of S35657 stainless steel welded section columns. On this basis, the critical width-to-thickness ratio limit of the compression plate was proposed. Finally, the test results and the simulation results were compared with the calculation results of load-carrying capacities for local buckling in the European code (EN1993-1-4), the American code (SEI/ASCE8-02), the Chinese specification (CECS410:2015), the direct strength method (DSM) and the continuous strength method (CSM). Based on the effective width method and DSM, two new approaches to calculate the load-carrying capacity for local buckling were proposed and demonstrated to obtain reasonable accuracy.