耦合地震作用下的MRD与LRB混合控制结构动力分析

为改善铅芯橡胶支座(LRB)隔震结构的减震效果和适用范围,研究双向耦合地震作用对减震效果的影响。提出3种磁流变阻尼器(MRD)与LRB隔震混合方案,建立其双向耦合地震作用下的动力分析模型并推导出振动控制方程。对7层MRD与LRB隔震混合控制结构进行地震反应分析,3种混合方案在3种工况荷载作用下的相对加速度峰值、相对速度峰值、相对位移峰值和层间剪力峰值分别比LRB隔震结构有不同程度的降低。当考虑竖向地震作用时,随着竖向地震作用的加大,结构的地震反应有小幅度的增加,但各种结构方案都具有良好的减振效果。表明各混合方案在各种工况下的各项地震反应均得到了更好的控制,而混合方案3的减震效果更加明显。

SEISMIC RESPONSE OF HYBRID VIBRATION CONTROL STRUCTURE WITH MRD AND LRB UNDER COUPLING EARTHQUAKE

In order to improve the effect of shock absorption and the application range of base-isolated structure with lead rubber bearing (LRB) and study the influence of the action of coupling earthquake in both horizontal and vertical direction to vibration control structures, three kinds of hybrid projects with magnetorheological damper (MRD) and LRB are proposed in the paper. The governing differential equation for the hybrid structure with MRD and LRB under the action of coupling earthquake in both horizontal and vertical direction is set up. Seismic response analysis of a 7-storey hybrid structure with MRD and LRB is carried out. Compared with sliding base-isolated structure, all of the peak values of various seismic responses of three hybrid projects are reduced. The results of dynamic analysis show that the seismic responses of hybrid structure with MRD and LRB get better control than sliding base-isolated structure under various loading conditions and that the control effect of the third hybrid project is the best.