复合材料层合梁结构在线损伤检测

复合材料层结构在服役过程中关键部位的裂纹或分层损伤累积发展到一定程度，常出现损伤突变现象，导致结构局部刚度突发性降低和结构性能下降，通过粘贴或埋入复合材料结构中的小型电片构成结构动态响应的激励和检测系统、以小波分析技术从应信号中识别结构损伤信息，可主动在线检测服役中的复合材料结构力学性能的突变，准确捕获结构突发损伤的时刻，这项研究将为许多在役中人们无法直接观察或量测的复合材料结构的在线健康监控提供新的技术支持。

Online damage detection for laminated composite beam

During the service of composite material structures, crack or delamination in their key components will continuously accumulate, and finally lead to a sudden increase of structural damage. This will result in an abrupt reduction of local stiffness of composite material structures and perturbations to the structural dynamic responses. Using piezoelectric patches bounded or embedded in composite material structures as actuators and sensors, the system for exciting the structure and sensing its dynamic response can be established. Extracting damage information from the response and monitoring the perturbations of structural dynamics can be implemented by using wavelet analysis. This will conduce to the capture of the accurate time of damage occurrence. The method developed in this paper can help build the system of online damage detection and health monitoring of composite material structures when they cannot be directly observed or measured.