Numerical simulation for restoring force of a SMA-rubber bearing

SMA-rubber bearing is a type of seismic isolation device dissipating energy with hysteretic effect of superelasticity of shape memory alloy(SMA) material.Based on an isolator's concept design,a series of pseudo-static tests for a SMA-rubber bearing were conducted and its excellent seismic isolation and energy dissipation performances were verified with the test results.For structural engineers to gain the mastery of seismic isolation characteristics of SMA-rubber bearings,the linear least square data fitting technique and the differential restoring force model commonly known in structural analysis software were used to simulate horizontal force of an isolator.Then,its restoring force-displacement hysteresis loop and performance parameters were compared with those of the test data.It was found that the test results match closely with those obtained from the above-mentioned simulation.Thererfore,the proposed simulation method was helpful for establishing an SMA-rubber isolator element with the existing structural analysis software and application of SMA-based isolation bearings in engineering structures.