工作应变模态时域识别方法研究
|
摘要
由于应变型指标比位移型指标对结构损伤具有更好的识别能力,在考虑了环境激励的优越性的情况下,借鉴环境激励下位移模态时域识别方法,提出了基于应变模态特征系统实现的时域识别方法。采用随机减量技术对随机应变响应信号进行预处理,得到系统的应变自由衰减曲线,近似获得应变脉冲响应数据。构造Hankel矩阵,通过奇异值分解得到该系统的最小实现,最后对最小实现状态矩阵进行特征值分解,推导得到应变模态参数的时域识别方法。
Strain type index is more sensitive to structure damage than displacement type index.In consideration of the superiority of environment encourage and according to time domain identification method of the displacement mode shape,the time domain identification based on the eigensystem realization of strain mode shape is put forward.The random strain response signals of structure are pre-treated by the random decrement technology.The free damped curve of strain is obtained and its impulse response data is also obtained.Then the Hankel matrix is established.The minimal realization of such system was obtained by the method of singular value decomposition.Furthermore,the eigenvalue matrix of the minimal realization is decomposed to deduce the time domain identification method of the parameter of strain mode shape.
Strain type index is more sensitive to structure damage than displacement type index.In consideration of the superiority of environment encourage and according to time domain identification method of the displacement mode shape,the time domain identification based on the eigensystem realization of strain mode shape is put forward.The random strain response signals of structure are pre-treated by the random decrement technology.The free damped curve of strain is obtained and its impulse response data is also obtained.Then the Hankel matrix is established.The minimal realization of such system was obtained by the method of singular value decomposition.Furthermore,the eigenvalue matrix of the minimal realization is decomposed to deduce the time domain identification method of the parameter of strain mode shape.
引文
[1]李德葆,陆秋海.实验模态分析及其应用[M].北京:科学出版社,2001.
[2]顾培英,丁伟农.模态试验在梁损伤诊断中的应用研究[J].振动与冲击,2004,23(3):60-63.
[3]顾培英,陈厚群,李同春,邓昌.应变模态技术诊断梁结构损伤[J].地震工程与工程振动,2005,25(4):50-53.
[4]顾培英,陈厚群,李同春,邓昌.应用应变模态试验技术诊断模型渡槽结构损伤[J].河海大学学报,2006,34(4):422-425.
[5]顾培英,邓昌.基于环境激励下的工作应变模态频域识别方法[J].振动与冲击,2008,27(8):68-70.
[6]曹树谦,张文德,萧龙翔.振动结构模态分析:理论、实验与应用[M].天津:天津大学出版社,2001.
[2]顾培英,丁伟农.模态试验在梁损伤诊断中的应用研究[J].振动与冲击,2004,23(3):60-63.
[3]顾培英,陈厚群,李同春,邓昌.应变模态技术诊断梁结构损伤[J].地震工程与工程振动,2005,25(4):50-53.
[4]顾培英,陈厚群,李同春,邓昌.应用应变模态试验技术诊断模型渡槽结构损伤[J].河海大学学报,2006,34(4):422-425.
[5]顾培英,邓昌.基于环境激励下的工作应变模态频域识别方法[J].振动与冲击,2008,27(8):68-70.
[6]曹树谦,张文德,萧龙翔.振动结构模态分析:理论、实验与应用[M].天津:天津大学出版社,2001.
版权所有：© 2023 中国地质图书馆 中国地质调查局地学文献中心