基于小波变换的层间隔震结构地震响应分析

Seismic Response Analysis of Inter-story Isolation Structures Based on Wavelet Transformation

利用小波多分辨率分析将地震动加速度分解为多频段小波分量,并运用复模态方法推导其计算层间隔震体系在地震作用下的动力响应公式,讨论各频段地震信号及结构响应的能量分配。同时利用小波时频工具分析地震动能量在时频域内的分布对层间隔震结构响应的影响,进而为考察地震动非平稳性对层间隔震结构非线性分析的影响提供方法。利用小波分析的以上优势,对一典型层间隔震结构分别进行弹性和弹塑性分析,结果表明弹性体系在地震作用下的响应可由该地震波各小波分量的响应叠加而得,地震动能量在时间上的集中会对层间隔震结构响应产生不利影响。

In this study,ground motion acceleration time history was decomposed into multiband wavelet components using the wavelet multiresolution analysis method,and a dynamic response formula for an interstory isolation structure under earthquake action was deduced using the complex modal method.The resulting seismic signals and displacement energies in a distinct frequency channel are discussed.The impact of earthquake energy distribution in the timefrequency domain on structural response was analyzed using wavelet timefrequency analysis tools,which provide a method of analyzing the nonlinear response of interstory isolation structures.Finally,the elastic and elastoplastic responses of a typical interstory isolation structure under earthquake excitation are analyzed using wavelet analysis.The results show that the elastic response can be the superposed seismic response of each wavelet component.Therefore,energy concentration of earthquake ground motion in the time domain can cause an adverse effect on interstory isolation structures.