中文摘要：

利用光纤光栅(FBG)传感器对修补结构中修补片下的裂纹再次扩展进行监测。在循环加载情况下,修补片下的裂纹会再次扩展,且随着裂纹扩展长度的增加,FBG的反射谱也随之变化。借助裂纹处有限元模型模拟得到的应变场分布,计算了裂纹扩展到不同长度时FBG的反射谱响应。模拟和检测结果证实了FBG反射谱的变化和裂纹扩展长度之间的关系,表明修补片下裂纹扩展长度可由FBG传感器的反射谱变化来评估。

英文摘要：

A FBG sensor is used to monitor the propagation of crack in the repaired patch under cyclic loading condition.As the number of cyclic loading increases,the crack length will extend and the reflection spectra of FBG sensor are found to change.The reflection spectra of the FBG for different crack lengths have been calculated by the finite-element model of the strain field that results from a crack.The relationship between the spectral change and the crack length is verified by the theoretic analysis and the e...