Structural health monitoring based on area sensing technology using distributed long-gauge FBG strain sensors
Most sensors for structural testing and health monitoring are “point” sensors which strongly limit the ability to announce the correct structural heath status, especially in noise environment. The corresponding monitoring method is one of the research hotspots and still needs to be developed. In this study, area sensing technology based on long-gauge fiber optic bragg grating sensors will be introduced. Numerical simulations and experimental investigations are performed to develop structural damage detection, response reconstruction and finite element (FE) model updating based on area distributed FBG strain sensing technology. It includes three aspects: (a) a novel damage detection method using quasi-static macro strain based on the advanced complete ensemble empirical mode decomposition adaptive noise (CEEMDAN) technology is put forward to detect and localize damages; (b) a novel macro-strain reconstruction approach is proposed to reconstruct dynamic macro-strain response induced by structural vibration from limit measurement acquired by the deployed FBG sensors, and dynamic displacement response is therefore estimated using the measured and reconstructed macro strain; (c) a model updating method is present using very limited measured modal macro strain vectors and modal frequencies to update the structural model. Results demonstrated the applicability of area distributed FBG strain sensing technology in structural health monitoring and the corresponding proposed methods have potential for structural health monitoring in real applications.