基于互相关函数幅值向量的结构损伤检测实验研究

进行了基于互相关函数幅值向量(cross correlation function amp litude vector,CorV)的受随机激励结构损伤检测的实验研究。以一个复合材料单跨梁为实验对象,通过在梁的局部位置上安装夹板,改变夹板对结构附加刚度,来模拟结构的损伤。对结构施加随机激励,分别用加速度传感器和应变传感器采集结构的响应信号,计算结构在损伤前后的CorV,使用互相关函数幅值向量置信度准则(cross correlation function amp litude vector assurance criterion,CVAC)来度量结构受损前后CorV的变化。结果表明,结构损伤前后的CorV之间的CVAC较完好结构之间的CVAC有明显下降;分析结构损伤前后CorV中分量的相对变化,可确定损伤产生的区域。使用互相关函数幅值向量,只需要测量结构在随机激励作用下的时域响应信号,就可检测出结构损伤的存在及损伤的位置。因此本文所采用的方法可应用于环境激励下的结构健康监测。

Experimental Study of Structural Damage Detection Using Cross Correlation Function Amplitude Vectors

The paper conducted an experimeatal study of randomly-excited structural damage detection using cross section function amplitude vectors(CorV).Taking a composite beam of a single support as the object of experiment,it simulated structural damage by changing the stiffness of reinforced patches which have been clamped on the local region of the beam.The beam was randomly excited and its structural response signals were acquired by employing acceleration sensors and strain sensors separately.Then the CorVs between damaged structure and intact structure were calculated,and the changes of the CorVs were measured through using the cross correlation function amplitude vector assurance criterion(CVAC).The calculation results show that the CVAC among the CorVs between damage structure and intact structure decreases remarkably.Damage locations can be identified by analyzing the relative change in the CorVs between damaged structure and intact structure.The use of CorVs only requires the measurement of time domain response signals of a structure under random excitation in order to detect structural damage and its locations.Therefore the approach presented in this paper can be applied to the structural health monitoring under ambient excitation.