Theoretical and Experimental Investigations on the Application of Superelastic Shape Memory Alloys in Seismic Engineering

This paper presents an extensive experimental program and main results of shaking table tests performed on reduced-scale steel frame model with and without passive energy dissipation devices. The goal of this work was to assess the effectiveness of the proposed energy dissipation devices in reducing dynamic response of structures subjected to strong seismic excitations. Innovative re-centering hybrid shape memory alloy friction devices (HSMAFD) which consist of pre-tensioned superelastic shape memory alloy (SMA) wires and friction devices (FD) were considered. The most important property of the SMA-based hybrid friction device is integration with stable large energy dissipation capacity and re-centering feature. In the shaking table tests, several representative seismic signals as well as white noise motion were used as input energy. The comparisons of dynamic behaviors, i.e. storey displacements, interstorey drifts and storey accelerations, of structural model with and without SMA-based RCD under seismic loading were conducted. The results show that HSMAFD were effective in suppressing the dynamic response of building structures subjected to strong earthquakes by dissipating a large portion of energy through their hysteretic loops. Moreover, the structures were able to undergo strong earthquakes without remarkable residual drift due to the re-centering feature of the devices.