Patch Repair and Structural Health Monitoring of Fatigue-Cracked Aging Aircraft Panels

发展老化飞机结构维修技术，延长老化飞机的使用寿命已成为迫切需要。本课题从修复后的飞机结构面板结构健康监测的角度出发，研究了粘合纤维增强聚合物（FRP）复合贴片修复技术。主要研究结果总结如下：基于二维有限元法和三维有限元/边界元结合方法，提出了玻璃钢复合材料修补裂纹飞机结构板疲劳裂纹扩展行为的数值模拟方法。提出了一种识别修复后飞机结构板疲劳裂纹和剥离面位置和形状的方法。研制了在贴片表面安装光纤布拉格光栅（FBG）传感器的应变测量传感器系统。基于非线性数学规划方法，开发了玻璃钢复合材料贴片的设计系统。对修复技术在实际应用中存在的问题进行了探讨，并进行了可行性研究。

Developing the repair technology of aging aircraft structures has been desired to extend the service life of aging aircraft. In this research project, the repair technology using bonded fiber-reinforced polymer (FRP) composite patches has been investigated from the viewpoint of structural health monitoring of repaired aircraft structural panels. The main results are summarized as follows :1.Based on a two-dimensional FEM and a three-dimensional combined FEM/BEM, the numerical simulation method of the fatigue crack growth behavior in cracked aircraft structural panels repaired with a bonded FRP composite patch was presented.2.The method for identifying the locations and shapes of fatigue crack and disbond fronts in repaired aircraft structural panels was presented.3.The strain measuring sensor system using fiber Bragg grating (FBG) sensors installed on the patch surface was developed.4.Based on a nonlinear mathematical programming method, the design system of the FRP composite patches was developed.5.The issues in practical use of repair technology were examined, and the feasibility study was made.