Numerical analysis and parametric study on stainless steel replaceable shear link under cyclic loading

This study presents a numerical comparison of replaceable shear link beams made of two grades of stainless-steel duplex S2205 and austenitic S31608, to that of conventional cast steel (G20Mn5QT) under cyclic seismic loading. 3D finite element models were developed in ABAQUS and tested under the AISC 341 − 16 cyclic loading procedure. The models were also validated using experimental hysteresis curves, with low root mean square error of 1.6 kN for shear forces and a mere 4.57% deviation in cumulated energy dissipation. A comprehensive parametric study ensued, varying the web thickness, flange thickness and number of stiffeners in the web. The findings indicate that the stainless steels exhibited superior cyclic performance than cast steel. Austenitic links dissipated approximately 55% more energy compared to the cast steel and achieved an overstrength factor of 3 (versus 1.55 for cast steel). The duplex links achieved approximately 22% higher peak strength compared to cast steel and 7.5% additional energy dissipation compared to cast steel with an overstrength factor of 2.55. Parametric analysis uncovered an optimum link configuration with a 12 mm web and two stiffeners in between, where strength and ductility are balanced in the optimal way. The best design achieved FEMA-356 acceptance criteria of performance in 74.5% of austenitic and duplex cases. The findings highlight the enhanced ductility, energy absorption and seismic capacity offered by stainless steel shear links, and the research provides quantified advice for design so that they may be incorporated into high-performance seismic design systems.