基于负刚度理论的新型减震器试验

Experiment on New Type of Passive Vibration Isolator Based on Negative Stiffness Theory

在参考现有理论与有限元分析的基础上,以加速度响应、加速度均方差和减振率3个评价指标来研究基于负刚度理论的新型被动减震器的减震效果,论证了该装置的适用性。按照试验要求制作了单榀三层钢框架和减震器模型,并对框架模型进行了配重以模拟实际情况,分别选用El Centro波、Taft波、人工波和设计反应谱生成的波作为地震荷载。对安装该减震器的单榀三层钢框架进行振动台试验。结果表明:在不同地震波的作用下减震器均发挥作用,不同测点处的加速度响应、加速度均方差和减振率3个指标均低于无控结构,减震器具有比较好的减震效果;不同水准地震动激励下,模型结构顶层、二层及一层最大加速度响应的减振率分别达到45.01%,26.32%,13.57%,其最大加速度均方根响应的减振率则分别达到53.01%,31.83%,19.59%,安装负刚度减振装置的钢框架模型结构的加速度响应得到了有效控制。

Based on the existing theory and finite element analysis,the vibration reduction effect of the new type of passive vibration isolator based on negative stiffness theory was studied by acceleration response,acceleration mean square deviation and vibration reduction rate,and the applicability of the device was demonstrated.According to the test requirements,a single threestory steel frame and a passive vibration isolator model were made,and the weight of the frame model was balanced to simulate the actual situation.El Centro wave,Taft wave,artificial wave and the wave generated by the design response spectrum were selected as seismic loads.The shaking table test on the single three-story steel frame installed with passive vibration isolator was carried.The results show that under the excitation of different seismic waves,the passive vibration isolator can control the response of structure.Acceleration response,acceleration mean square deviation and vibration reduction rates at different measuring points are lower than those of uncontrolled structure.Under different levels of seismic excitation,the vibration reduction rates of the maximum acceleration responses of the top,second and first floors of the model structure are 45.01%,26.32% and 13.57% respectively,while the vibration reduction rates of the maximum root mean square acceleration responses of the model structure are 53.01%,31.83% and 19.59% respectively.The acceleration response of the steel frame model with negative stiffness passive vibration isolator is effectively controlled.