基于大直径SMA杆的摩擦复合阻尼器滞回性能研究

Research on hysteresis performance of SMA friction composite damper based on large diameter SMA bar

提出一种兼具自复位和高耗能的新型形状记忆合金(Shape Memory Alloys,SMA)摩擦复合阻尼器,该阻尼器由SMA杆自复位装置和摩擦耗能装置并联组成,可以实现大直径SMA杆和摩擦阻尼器协同工作。首先,对经过高温热处理的直径10 mm的SMA杆进行室温下循环拉伸试验,并对其力学性能进行数值模拟,模拟结果和试验结果吻合较好。其次,利用Abaqus有限元分析软件建立了阻尼器的数值模型,分析了位移幅值、摩擦力和SMA杆直径对阻尼器等效刚度、单位循环耗能和等效阻尼比等力学性能的影响。研究结果表明:新型SMA摩擦复合阻尼器滞回曲线呈现“旗帜”型,具有良好的自复位和耗能能力。随着摩擦力的增大,阻尼器的耗能能力增强,但残余位移变大;随着SMA杆直径的增大,阻尼器的刚度及承载力变大,同时残余位移减小。

A novel Shape Memory Alloy(SMA)friction composite damper with self-centering and large energy dissipation capacity is proposed.The damper is composed of self-centering device based on large diameter SMA rod and frictional energy dissipation device.The large diameter SMA rod and the friction damper can work together in parallel.Firstly,the cyclic tensile test of SMA rod with diameter of 10 mm after high temperature heat treatment is carried out at room temperature,and its mechanical properties are numerically simulated.The simulation results are in good agreement with the test results.Secondly,the Abaqus software is used to establish the numerical model of the damper,and the effects of displacement amplitude,friction force and the diameter of SMA rod on the mechanical properties of the damper,such as equivalent stiffness,energy dissipation and equivalent damping ratio,are analyzed.Results show that the hysteresis curve of the novel SMA friction composite damper presents a"flag"shape,and has good self-centering and energy dissipation capacity.With the increase of friction force,the energy dissipation capacity of the damper increases,and the residual displacement increases.With the increase of the diameter of SMA rod,the stiffness and strength of the damper increase,while the residual displacement decreases.