基于互相关函数幅值向量的结构损伤定位方法研究

在利用互相关函数幅值向量（Correlation Function Amplitude Vector，CorV）进行结构损伤检测的方法基础上，进一步提出了利用互相关函数幅值向量来确定受损结构的损伤位置的方法。通过在随机激励下不同测点的时域响应求得结构互相关函数幅值向量后，对损伤前后结构的互相关函数幅值向量进行二阶差分处理，根据差分处理后的互相关函数幅值向量分布图可以直观地判别出结构损伤的位置。用一个四边固支板和一个四层楼房基准模型的损伤定位为算例，验证了所提出方法的有效性和准确性。算例表明，用所提出的方法只需要测量结构受随机激励的时域响应，就可同时确定多处结构损伤的位置，且具有较好的抗测量噪声能力。因此，所提出的方法可应用于环境随机激励下的结构健康监测技术。

STRUCTURAL DAMAGE DETECTION WITH RANDOM EXCITATION AND CORRELATION FUNCTION AMPLITUDE VECTOR

The principle of structural damage detection based on Correlation Function Amplitude Vector(CorV) is presented in this paper.It is verifide that under random excitaion with specific frequency spectrum,the CorV of structure only depends on the frequency response matrix of the structure,and the normalized CorV has a specific shape.Therefore with the correlativing and the relative change between the CorVs obained from the intact and the damaged structure under the same random excitation,the damage in the structure can be detected with the concept of Correlation function amplitude Vector Assurance Criterion(CVAC).Furthermore,based on this damage detecting method,a damage locating method is proposed.To locate damages in the structure,second order difference handling of CorVs are used and it is found that the damaged location will emerge and easy to be identifed. This approach is demonstrated with the damage locating examples of a 4 side-clamped plate and a benchmark model of ASCE.The damage detecting and locating results show the feasibility of this method and can be used in the structural health monitoring with ambient excitaion.