SELF-CENTERING CAPABILITY OF SHAPE MEMORY ALLOY (SMA)-BASED SUPE RELASTICITY-ASSISTED SLIDER (SSS)

The self-centering capabilityy, emphasized in design codes as a fundamen tal feature of aseismic isolation systems, is investigated foor the Shape memory alloy (SMA)-based Superelasticity-assisted Slider (SSS).Restoring force in SSS is as sociated with austenitic SMA wires in order t o properly re-center flat sliders. Energy considerations are e xamined first as an insight into the problem, reve aling also the governing parameters. The self-centering capa bility is then investigated through an extensive parametric study of the isolated structures idealized as single-degree-of-freedom systems subjected to a l arge group of recorded earthquakes. According to the res ults obtained from extensive nonlinear time-h istory analyses,residual displacement after an earthquake a nd the cumulative build-up of displacements aft er a series of successive earthquakes depend on both struc tural properties and ground motion characteristics. SSS exhibits an acceptable self-centering capability, satisfying code provisions.

Keywords:

Aseismic Isolation , Slid ing Systems , Shape Memory Alloys , Superelasti city , Self-centering