【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。更多还原

【Abstract】 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.更多还原