东南大学学报（自然科学版）2012，Vol.42Issue(2)：339-345,7.DOI:10.3969/j.issn.1001-0505.2012.02.028
基于Morlet小波变换的结构密集模态参数识别
Modal identification of closely spaced modes based on Morlet wavelet transform
摘要
Abstract
In order to improve the precision of the modal parameter identification of closely spaced modes, an identification method and procedure based on Morlet wavelet transform is proposed. Firstly , the mechanism of modal overlap is studied through formula derivation. The concept of closely spaced modes is defined and quantified with an index, the frequency ratio of two adjacent modes, to assess the validity of modal identification by Morlet wavelet transform. Secondly, in order to limit the edge effect and noise pollution, the modal identification method using continuous wavelet transform is modified, and then an interactive algorithm for the center frequency of the mother wavelet is proposed. The theoretical results show that at the fixed frequency ratio of two adjacent modes, the severity of modal overlap is greater with the increase of the damping ratios and the difference between the damping ratios of the adjacent modes. The results of the numerical simulation example show that the modified modal identification method can effectively identify modal parameters of structures and the identification precision is high.关键词
Morlet小波/参数识别/密集模态/模态混叠/方法改进Key words
Morlet wavelet/ modal identification/ closely spaced modes/ modal overlap/ method improvement分类
建筑与水利引用本文复制引用
孙鹏,丁幼亮,张劲泉,李爱群,邓扬..基于Morlet小波变换的结构密集模态参数识别[J].东南大学学报（自然科学版）,2012,42(2):339-345,7.基金项目
国家自然科学基金资助项目(51178100)、交通运输部“十二五”重大科技专项资助项目(2011318223190)、江苏省自然科学基金资助项目(BK2011141)、江苏省高校“青蓝工程”优秀青年骨干教师资助项目、东南大学重大科学研究引导基金资助项目. （51178100）
