EXPERIMENTAL STUDY ON SEISMIC BEHAVIOR OF ASSEMBLED BUCKLING-RESTRAINED BRACE WITH PERFORATED STAINLESS-STEEL PLATE

To improve the durability of energy dissipation members in coastal engineering structures, assembled stainless steel buckling-restrained braces (BRBs) are proposed, and its inner core plate is made of austenitic S304 and duplex S2205 stainless steel respectively. The inner core plate and outer restraint plate are perforated to achieve fixed energy dissipation and facilitate the observation of the damage to the brace subsequent to an earthquake. The hysteretic characteristics and seismic performance of BRBs with different materials are analyzed through the pseudo-static test, and the cyclic loading test was simulated by ABAQUS. The results show that the prefabricated BRBs with the perforated flat panel have a simple structure style and a good performance of overall stability. The hardening degree of the BRBs with different inner core materials varies greatly. It is suggested that the stiffness factor of austenitic S304 stainless steel BRBs should be 0.1 and that of duplex S2205 stainless steel BRBs should be 0.02. The equivalent viscous damping ratio of both stainless steel BRBs is about 0.4 under the L/100 displacement amplitude, which shows good energy dissipation capacity. Under the same loading regime, the fatigue life, plastic deformation capacity and total energy dissipation of stainless steel BRBs are much higher than those of Q235 and Q550 ordinary steel BRBs with similar yield strength respectively, which presents better seismic performance. The fitted cyclic constitutive parameters of the inner core plate can describe the hysteretic characteristics of BRBs, and the modeling method adopted can consider both computational accuracy and computational efficiency.