【摘要】 目的分析基底隔震结构在地震波以及地震波各个频段作用下的位移、等效静力、基底剪力.方法采用小波分解的方法对汶川地震近震区的水平地震动输入加速度进行分解,对基底隔震体系在不同频段地震动作用下进行动力学时程分析,并与未隔震体系进行对比研究.结果隔震结构在0~0.39 Hz、0.39~0.78 Hz、0.78~1.56 Hz等低频段作用下的位移反应远远大于6.25~12.5 Hz、12.5~25 Hz、25~50 Hz、50~100 Hz等高频段的位移反应,在6.25 Hz以上的频段,出现隔震结构的位移小于未隔震结构的位移,等效静力也是如此.在卧龙波以及各个频带作用下,隔震结构基底剪力远远小于未隔震结构的基底剪力.结论相比未隔震结构而言,基础隔震结构大大地降低了上部结构的地震反应,低频段地震波对结构作用很大,高频段可以放大高阶振型的作用,而隔震层起到一个低通滤波器的作用,可以滤去地震波的一些高频成分.更多还原

【Abstract】 This paper aims to analyze seismic dynamic response of the base isolated structure under seismic waves,including displacements,equivalent static forces,base shear forces etc. Using the wavelet decomposition method,the input acceleration of horizontal earthquake shock near the Wenchuan earthquake zone was decomposed. Dynamical histories of the base isolated structure system under earthquake with different bands were analyzed and compared with the non-isolation system. It is found that displacements of the isolated structure under low frequency bands( 0 ~ 0. 39 Hz,0. 39 ~0. 78 Hz,0. 78 ~ 1. 56 Hz etc.) are far greater than that under high frequency bands( 6. 25 ~ 12. 5Hz,12. 5 ~ 25 Hz,25 ~ 50 Hz,50 ~ 100 Hz). It is also observed that under bands above 6. 25 Hz,displacements and equivalent static forces of the isolated structure are smaller than that of the non-i-solated structure. Under the Wolong waves and bands,base shear forces of the isolated are much smaller that that in non-isolated structure. Conclusion is that compared with the non-isolated structure,the base isolated structure reduces the seismic response of upper structure greatly. Low-frequency earthquake has huge impact on the structure,while high-frequency bands can amplify responses of high modals. The isolation layer can play a low-pass filter to filter some high frequency components of seismic waves.更多还原