【摘要】 采用Wilson-θ法,分析了复合地基碎石褥垫层上结构在不同地震动参数El-Centro波作用下的动力反应,假设上部结构为摩擦隔震结构,得到了结构在不同强度地震作用下的动力反应,并与基底固定结构进行了比较。采用了减震系数μr来评价减震的效果,分析结果表明:褥垫层对上部结构有明显的减震作用,并且减震效果随垫层与基础间摩擦系数的减小而显著增加;减震效果还与输入的地震动大小有关,输入的地震动越大,μr值越小。更多还原

【Abstract】 In this paper,Wilson-θ’s time integration scheme is used to analyze the structures with composite foundation cushion. The superstructure is a base-friction-isolated structure,which is isolated from the foundation by the cushion and the friction coefficient between the cushion and the base is constant. Then,the nonlinear responses of structures under El-Centro wave with different seismic parameters are obtained,and the responses are also compared with that of the fixed base structure. Seismic-reduction factor,μr,is introduced to evaluate the vibration reduction effectiveness. With the decreasing of the friction coefficient,vibration reduction improves obviously. It also indicates that the effectiveness of vibration reduction is correlated with the intensity of input seismic wave; the more intensive the seismic input,the less the value of μr.更多还原