Experimental Investigation of Aluminum Alloy and Steel Core Buckling Restrained Braces (BRBs)

Buckling restrained braces (BRBs) display balanced hysteretic behavior under reversed cyclic tension and compression forces and dissipate a significant amount of seismic energy during credible earthquakes. This paper reports on an experimental investigation of newly developed BRBs with different core materials (steel and aluminum alloy) and end connection details. A total of four full-scale BRBs with two steel cores and outer tubes (BRB-SC4 and BRB-SC5) as well as two with aluminum alloy cores and aluminum outer tubes (BRB-AC1 and BRB-AC3) with specific end details were designed as per the AISC Seismic Provisions, manufactured and cyclically tested. These tests made it possible to compare the impact of the steel and aluminum alloy material characteristics on the hysteretic behavior and energy dissipation capacities. The proposed steel and aluminum alloy core BRBs with various end details achieved the desired behavior, while no global buckling occurred under large inelastic displacement cycles.