In previous study the failure initiation and development in hybrid fiber laminates was successfully monitored and determined. In current investigation a novel damage monitoring approach is proposed for hybrid laminates by combining different optical strain measurement techniques namely digital image correlation (DIC), fiber Bragg grating sensors (FBG) and infrared thermography (IRT) with smoothing element analysis (SEA). This viable experimental procedure eliminates the effects of global/local nature of optical strain measurement systems on heterogeneous damage accumulation and is a two-step approach. First, all optical sensing systems together with conventional strain gauges are utilized concurrently to indicate the differences in the measured strains and monitor damage accumulation under tensile loading. This demonstrates how failure events disturb the measurement capabilities of optical systems, which can cause a miscalculation of hybrid effect in hybrid-fiber laminates. The second step involves the utilization of SEA algorithm for discretely measured DIC displacements to predict a realistic continuous displacement/strain map and rigorously mitigate the inherent noise of the full field optical system. Remarkably, for large deformation states in hybrid composites, the combination of SEA/DIC enables early prediction of susceptible damage zones at stress levels 30% below material strength.

在之前的研究中，成功​​监测和确定了混合纤维层压板的失效开始和发展。在当前的研究中，通过将不同的光学应变测量技术，即数字图像相关 (DIC)、光纤布拉格光栅传感器 (FBG) 和红外热成像 (IRT) 与平滑元素分析 (SEA) 相结合，提出了一种用于混合层压板的新型损伤监测方法。这种可行的实验程序消除了光学应变测量系统的全局/局部性质对异质损伤累积的影响，并且是一种两步法。首先，所有光学传感系统与传统应变计同时使用，以指示测量应变的差异并监测拉伸载荷下的损伤累积。这表明故障事件如何干扰光学系统的测量能力，这可能导致对混合纤维层压板的混合效应的错误计算。第二步涉及利用离散测量的 DIC 位移的 SEA 算法来预测现实的连续位移/应变图，并严格减轻全场光学系统的固有噪声。值得注意的是，对于混合复合材料的大变形状态，SEA/DIC 的组合能够在低于材料强度 ​​30% 的应力水平下早期预测易受损伤的区域。第二步涉及利用离散测量的 DIC 位移的 SEA 算法来预测现实的连续位移/应变图，并严格减轻全场光学系统的固有噪声。值得注意的是，对于混合复合材料的大变形状态，SEA/DIC 的组合能够在低于材料强度 ​​30% 的应力水平下早期预测易受损伤的区域。第二步涉及利用离散测量的 DIC 位移的 SEA 算法来预测现实的连续位移/应变图，并严格减轻全场光学系统的固有噪声。值得注意的是，对于混合复合材料的大变形状态，SEA/DIC 的组合能够在低于材料强度 ​​30% 的应力水平下早期预测易受损伤的区域。