Experimental and numerical study on stainless steel STS304 buckling-restrained braces

Stainless steel has gained increasing attention in construction due to its sustainability, excellent ductility, and superior resistance to corrosion and fire, making it especially suitable for use in seismic-prone areas. This study introduces all-stainless-steel assembled buckling-restrained brace (ASS-BRB), comprising rapidly installable and removable restraining units. All components of the proposed ASS-BRB are made from stainless-steel plates and bolts, combining the corrosion resistance and strain-hardening characteristics of stainless steel to ensure long service life and high post-yield stiffness. Experimental tests are conducted on a total of three austenitic stainless steel STS304 BRB specimens to evaluate their cyclic behaviour. The resulting hysteretic response, failure modes, energy dissipation capacities, strength-adjustment factors, cumulative plastic deformation (CPD) and post-yield stiffness are analyzed. The STS304-BRBs demonstrated enhanced hysteretic performance, particularly significant higher stiffness at 2% and 3% strain amplitudes. Additionally, finite element models were created in ABAQUS, and their outcomes closely matched the experimental results, confirming the accuracy of the modeling approach. The developed stainless-steel BRBs are expected to contribute significantly to the advancement of resilient, durable, and corrosion-resistant seismic protection systems for built structures.