竖向近断层地震下隔震结构-非结构系统耦合控制研究

Under the action of vertical near-fault ground motions, it is easy to cause the amplification of seismic responses of the internal non-structural systems in isolated structures. In order to study the dynamic response control mechanism of isolated structures - internal non-structures under near-fault ground motions, an analytical model of the isolated structure - internal non-structural coupling system under vertical ground motions was established. The response control effect of non-structural elements with an additional vertical quasi-zero stiffness system was analyzed using the nonlinear time-history response analysis method. Based on the energy analysis method, the energy balance equation of the isolated structure - internal non-structural coupling system under vertical near-fault ground motions was established. The research results show that for isolated systems with different natural frequencies, when the vertical quasi-zero stiffness is used to control the seismic responses of non-structural elements, the damping effect is better. The vertical elastic recovery energy and damping energy dissipation of the controlled system are greater than those of the uncontrolled structure, and the seismic responses of non-structural elements can be effectively controlled by selecting an appropriate damping ratio.

竖向近断层地震动作用下易造成隔震结构内部非结构系统产生地震响应放大现象。为研究近断层地震动下隔震结构-内部非结构的动力反应控制机理,建立了竖向地震动下隔震结构-内部非结构耦合系统分析模型。采用非线性时程反应分析方法分析了附加竖向准零刚度系统的非结构元件的响应控制效果。基于能量分析方法建立了竖向近断层地震动作用下隔震结构-内部非结构耦合系统能量平衡方程。研究结果表明对于不同自振频率的隔震系统,当采用竖向准零刚度对非结构元件进行地震响应控制时,减震效果较好。有控系统的竖向弹性恢复能和阻尼耗能要大于无控结构,通过选取合适的阻尼比可有效控制非结构元件的地震响应。