带预应力厚层橡胶支座隔震结构竖向地震反应谱分析

Analysis on vertically seismic response spectrum about seismically isolated structure with PRB

根据预应力厚层橡胶支座(PRB)的工作机理,建立了带PRB隔震结构的竖向隔震分析模型并推导相应的运动微分方程,研究了带PRB隔震结构竖向地震反应谱的特点,并通过算例分析了PRB竖向隔震、限位效果。研究表明:PRB对结构有竖向隔震功能,拉索可以防止支座出现受拉现象。同时,确定了PRB设计中的最优刚度比β=1.46,使得PRB的竖向隔震限位效果达到最佳。

According to the prestressed thick rubber bearing’s working principle,analytical model of vertically seismic isolation and the corresponding motion equationes were established.Furthermore,the characteristic of the vertically seismic response spectrum about seismically isolated structure with PRB was studied.Then,the effect of PRB’s vertically seismic isolation and its limiting about displacement was analysed.The results show that PRB has the capacity of vertically seismic isolation and flexible cable can effectly prevent the bearing from tension.Furthermore,when the PRB’s stiffness ratio is 1.46,it has the best capacity of vertically seismic isolation and limiting about displacement.