基于多传感器的裂纹扩展监测研究

A multi-sensor based crack propagation monitoring research

疲劳裂纹扩展是结构健康监测的主要问题之一,为了保证金属结构的可靠和安全运行,实时监测结构的疲劳裂纹扩展过程十分必要。针对结构裂纹扩展的问题,采用压电传感器(PZT)和电阻应变片两种传感器,提出结合能够连续监测结构损伤的被动监测方法以及对微小损伤敏感的主动监测方法对裂纹扩展进行综合监测,以提高裂纹扩展的监测水平。采用随机森林算法对裂纹长度进行识别,并使用D-S证据理论对两种传感器的识别结果进行数据融合,得到比单一传感器更准确、可靠的裂纹扩展识别结果。进行了基于应变和主动Lamb波的裂纹扩展监测实验研究,验证了该方法对提高裂纹扩展监测识别准确率的有效性和实用性。

Fatigue crack propagation monitoring research is one of the main problems of structural health monitoring.In order to ensure the reliable and safe operation of metal structures,it is necessary to monitor the fatigue crack growth process of structures in real time.Aiming at the problem of structural crack propagation,this paper adopts two sensors,PieZoelectric Transducers(PZT)and resistance strain gauge,and proposes a comprehensive monitoring method to combine crack monitoring with passive monitoring method for continuous monitoring of structural damage and active monitoring method sensitive to small damage,so as to improve the monitoring level of crack propagation.In this paper,the random forest algorithm is used to identify the crack length,and the D-S evidence theory is used to fuse the recognition results of the two sensors.The crack propagation recognition result is more accurate and reliable than the single sensor.In this paper,the experimental study on crack propagation monitoring based on strain and active Lamb wave is carried out.verifying the effectiveness and practicability of the method for improving the accuracy of crack propagation monitoring and identification.