固有模态函数振动传递率损伤识别实验研究

Experimental Study of Damage Identification Based on Intrinsic Mode Function Vibration Transmissibility

针对风荷载、地震荷载等存在但难以精确量测的问题,提出一种无需量测外荷载的新的损伤识别方法。将经验模态分解(Empirical Mode Decomposition,EMD)应用于结构损伤识别,通过求振动响应信号固有模态函数(Intrinsic Mode Function,IMF)的振动传递率,构建了一种新的结构损伤识别参数。对预置不同程度开胶损伤的玻璃幕墙试件进行动态测试,得到不同损伤程度下玻璃幕墙的固有模态函数振动传递率,与无损伤条件下的固有模态函数振动传递率进行比较来识别和评估玻璃幕墙开胶损伤程度。研究表明:此方法无需量测外荷载也能识别结构损伤,损伤参数值能反映损伤大小。

Traditional dynamic testing methods require the excitation measurement that is difficult to perform due to stochastic loading such as load produced by wind or earthquake.A new dynamic damage identification method is proposed in this paper based on the application of empirical mode decomposition（EMD） to structure damage identification.Seeking vibration transmissibility of intrinsic mode function（IMF） through experimentally recording vibration response signals,a set of dynamic damage identification parameters were constructed.Dynamic testing was carried out for glass curtain wall with different preestablished unglued damages,and vibration transmissibility of intrinsic mode function under different damages was obtained.Comparison between above vibration transmissibility with the one without preestablished unglued damage was carried out to identify and assess the damage of glass curtain wall.Results show that this method can identify structural damage without excitation measurement and the damage severity can also be reckoned through damage identification parameters.