干摩擦板-复位弹簧系统隔震性能研究

Research About Seismic Isolation Properties of Dry Friction Plate-reposition Spring System

从理论上分析了干摩擦板-复位弹簧隔震系统的隔震性能,建立了设置隔震系统结构离散多自由度体系运动方程,并计算了一个设置隔震系统结构在地震作用下的动力反应。计算结果表明,应用干摩擦板-复位弹簧隔震系统以后,结构具有较长的自振周期,隔震效果明显,楼层最大位移增加但沿结构高度分布趋于均匀化,最大层间位移值大幅度减少;依靠弹簧能够复位;接触面上的滑移摩擦作用能消耗传入上部结构的地震能量。决定隔震系统效率的关键因素是接触面摩擦系数与复位弹簧的刚度系数;接触面滑移摩擦系数与复位弹簧系数均取较低的数值时,隔震效率可以达到90%左右。

A theoretical analyzing approach about a class of seismic isolation system,dry friction plate-reposition spring system,was presented.It started from the formulation of the governing equation of multiply-degree of freedom system for structures equipped with this seismic isolation system.Computation results demonstrate that it has the three kinds of necessary functions required for an effective seismic isolation system.The relatively long vibration period provides the necessary isolation capability,the spring provides the reposition capability,and the friction forces at the contacting surface provide the seismic energy dissipation capability.It is also shown that the inter-storey drift resulted from seismic action could be drastically decreased on buildings equipped with this system,with the storey drift being enlarged but being distributed more evenly along the height.The friction coefficient and the string constant play significant roles in dictating the seismic isolation effectiveness.A combination of smaller friction coefficient and smaller spring constant could generate a seismic isolation effectiveness of about 90%