Seismic performance of multistory frames with novel self-centering friction SMA dampers

Owing to their advantageous properties of super-elasticity and shape memory effect, shape memory alloys (SMAs) can dissipate seismic energy and minimize post-earthquake structural damage. In this study, an improved SMA multi-linear constitutive model is proposed first, and a new material model based on OpenSees platform is developed. Secondly, a new self-centering friction damper (SCFD) is proposed by combining SMA and friction material, and a numerical model is established and validated by damper tests. Finally, detailed finite element models of RC frames equipped with SCFDs, buckling-restrained braces, and self-centering dampers are established. Peak and residual inter-story drift ratio of different cases are analyzed, and seismic control effectiveness of different energy dissipation devices is compared through comprehensive evaluation indices. The results show that the improved SMA multi-linear constitutive model can accurately characterize its hysteresis response. The SCFD reduces the residual inter-story drift ratio to below 0.1% under rare earthquakes and decreases the peak inter-story drift ratio by 43.5% compared to uncontrolled structures under extremely rare earthquakes, and structural function recovery can be achieved.