竖向地震动对摩擦摆隔震LNG储罐地震响应的影响

Effect of Vertical Ground Motion on Seismic Response of LNG Storage Tanks with Friction Pendulum System

为了研究竖向地震动对摩擦摆隔震LNG储罐地震响应的影响,由摩擦摆的滑块受力平衡推导出考虑竖向地震动的摩擦摆隔震系统的水平力与位移的滞回关系与隔震周期,指出LNG储罐考虑竖向地震动的必要性。引入由碟形弹簧和摩擦摆组合而成的三维基础隔震系统,讨论不同竖向地震动强度对LNG储罐的地震响应的影响,研究结果表明:LNG储罐地震响应必须考虑竖向地震动,尤其是竖向地震动强度较大时;竖向隔震周期0.4s,或者竖向阻尼比0.2~0.3,或者减小摩擦摆的摩擦系数与曲率半径,可以有效地降低竖向地震动对LNG储罐地震响应的影响。

Based on the forces balance of friction pendulum bearing slider,the isolation period and hysteretic relationship between horizontal force and displacement considering the vertical ground motion were derived to study the influence of vertical ground motion on the seismic response of Liquefied Natural Gas(LNG)storage tanks with friction pendulum isolation system.This study highlighted the need for vertical ground motion in LNG storage tank design.In this study,a three-dimensional base isolation system consisting of a disc spring and a friction pendulum bearing was introduced to investigate the influence of vertical ground motion intensities on the seismic response of LNG storage tanks.The results showed that the effect of vertical ground motion on the seismic response of LNG storage tank must be considered,especially when the vertical ground motion is strong.The effect can be effectively reduced under the following conditions:vertical base isolation period of 0.4s;vertical damping ratio in the range of 0.2 to 0.3;or reducing friction coefficient and curvature radius of friction pendulum bearing.