Experimental Study on Balance Design Concept of Self-Recovery and Energy Dissipation of Superelastic Shape Memory Alloy

Abstract:

Superelastic shape memory alloys have superior self-recovery properties， which can ensure the perfect self-centering performance of structures in engineering seismic applications. However， their energy dissipation capacity is very limited because of the flag-shaped hysteresis curve， which is difficult to meet the seismic demand of structures in earthquakes. Therefore， this paper explores to maximize the energy dissipation capacity of shape memory alloy system while preserving the self-recovery performance， via combining superelastic shape memory alloy with friction dampers. First， it conducts an in-depth study of the balance design concept of self-recovery and energy dissipation of shape memory alloy and proposes the system balance parameter and corresponding design formula. Then， it demonstrates the practicality of the balanced design concept and the accuracy of the theoretical design formula by the superelasticity performance test of shape memory alloy， the simple friction damper test， and the combined tensile test. The balance design concept proposed and its successful verification can well promote and guide the engineering seismic application of shape memory alloy.

Key words:shape memory alloy;superelasticity;energy dissipation capacity;balance design;friction damper