摘要
地震动是一个复杂的非平稳随机过程,基于傅立叶变换的传统谱分析方法已经难以发挥作用,小波变换因其在时-频两域都具有表征信号局部特征的能力而成为非平稳信号分析的有力工具。通过采用小波能量理论对一个三层钢筋混凝土框架-剪力墙模型地震模拟振动台试验实测数据进行了不同小波中心频率下的小波谱分析,探索了在同一地震中信号能量累积和能量累积变化率与结构动力特性变化的关系;提出了小波传递函数的方法并将其用于不同加载条件后结构模态参数的求解,清晰地得到了结构在不同地震后力学性能的退化趋势。
Earthquake motion is a complex non-stationary random process, and wavelet transform is a useful tool since it can provide an insight into the character of transient signals through time-frequency maps by the time variant spectral decomposition that traditional approaches based on Fourier transform are usually hard to accomplish. A scale model of three-story RC frame-share wall is made and tested on a shaking table; experimental data are analyzed by use of wavelet spectrum under different wavelet central frequency; then the relationships between structure dynamical properties and energy accumulation as well as rates of change of energy accumulation are discussed during the course of earthquake. A novel method called wavelet transfer method is proposed for estimating the structural modal parameters after enduring the processes of different kinds of earthquakes and the changing trend of structure dynamical properties are clearly got based on the method.
出处
《振动与冲击》
EI
CSCD
北大核心
2006年第5期32-36,共5页
Journal of Vibration and Shock
基金
国家自然科学基金(50408031)
辽宁省自然科学基金重点项目(20042149)
面上项目(20032120)资助
关键词
小波分析
小波谱
框-剪结构
传递函数
wavelet analysis, wavelet spectrum, frame-share wall structure, transfer function
