超弹性形状记忆合金自恢复与耗能平衡设计理念

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

摘要:

超弹性形状记忆合金具有优越的自恢复性能，在工程抗震应用中能够赋予结构完美的自复位性能，但由于其超弹性旗帜形本构关系，自身耗能能力十分有限，致使其难以满足结构地震下的抗震需求。探求在保留形状记忆合金自恢复性能的前提下，尝试将超弹性形状记忆合金与摩擦阻尼器组合应用，以使形状记忆合金系统的耗能能力最大化。首先，对超弹性形状记忆合金自恢复耗能平衡设计理念进行深入研究，引入系统平衡参数的概念，提出相应的配比设计公式；随后，通过开展形状记忆合金超弹性性能试验、简易摩擦阻尼器试验以及组合张拉试验，证明上述平衡设计理念的实用性以及平衡设计公式的可行性。平衡设计理念的提出以及其验证能够推进并指导形状记忆合金在工程抗震中的应用。

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.