Experimental investigation of shape memory alloy as passive energy dissipation device for seismic response reduction of buildings

An innovative passive energy dissipation device by utilizing the pseudoelastic property of Shape Memory Alloy (SMA) is developed and investigated in this paper. The main advantage of this device is the NiTi wires in kernel of the device are always in tension when subjected to earthquake excitations, which could conduct the avoidance of the buckling of the NiTi wires even with the small diameter wire. The cyclic loading-unloading tests of the wires are performed firstly on a MTS testing machine to investigate the dynamic properties of the NiTi wires and to train them for obtaining stable performance before they are connected with other components of the damper. Shaking table tests for a scaled 5-story steel frame with and without SMA dampers at the first story, subjected to various earthquake excitations, are conducted to verify the effectiveness of this damper to suppress the earthquake response. The results of the shaking table test demonstrate that this passive energy dissipation damper has great potential to mitigate the seismic responses of buildings.