Abstract:

Based  on strain modal analysis theory,a new strain modal shape factor was defined.The principles and methods to obtain structure strain modal shape from FRF were  derived.Meanwhile,the method was validated by a simply supported beam experiment.The results show that the method does not need to  measure the displacement mode,and  can quickly obtain the strain modal shape by  using strain gage to measure strain FRF information.  This method simplifies the process of strain modal experimental testing in structural damage identification.

Key words: strain mode, frequency response function(FRF), frequency response amplitude, strain modal shape coefficient, modal shape

摘要：

根据应变模态分析原理,定义了一个新的应变模态振型系数,提出了基于应变响应获取结构应变模态振型的一种简便方法,并通过简支梁实验进行了验证。研究结果表明,采用该方法无需测量位移模态,仅需采用单点激励，用电阻应变计测量结构上各测点的应变响应信息，即可获得被测结构应变模态振型，大大简化了应变模态在工程结构损伤识别中的实验检测分析过程。

关键词: 应变模态, 频响函数, 频响幅值, 应变模态振型系数, 模态振型