变摩擦作用FPS支座隔震体系效果分析

Research on seismic mitigation efficiency for FPS bearings with variable friction effect

根据拉格朗日方程建立了变摩擦作用FPS隔震体系的运动方程,采用MATLAB语言编制了求解程序计算体系的动力反应。结果表明:当FPS接触面摩擦系数较小时,变摩擦作用才对隔震效果有影响,但是对FPS支座的减震效果改善很小;当增加的附加压力较大时,减震效果可能降低。当摩擦系数大于0.1时,变摩擦作用对FPS支座的减震效果没有影响。可以认为采用无变摩擦作用、较低的常摩擦系数方案(推荐0.05),就能接近最佳的减震效果。

According to Lagrange’s equation,the governing equation for a base isolated structural system is established with a variable friction action FPS(friction pendulum system) bearing.Its solution is presented with software prepared from MATLAB language.The results show that variable action will exhibit its performance when the friction coefficient is rather small.In this case,it only has little influence to seismic mitigation efficiency.If the additional normal compression on contact surface became large,the seismic mitigation efficiency will even become worsen.It is also shown that when the friction coefficient is larger than 0.1,the variable action will no longer exhibit any influence to system dynamic response.It is considered that the non-variable action plus low friction coefficient FPS bearings might be an applicable methodology for the optimal seismic mitigation efficiency.