Experimental investigation on structural damage detection scheme based on distributed fiber optic sensors

An advanced structural damage detection and assessment scheme based on distributed fiber optic sensing techniques have been presented in our recent research, which are expected to bring up a new way for both static and vibration-based structural health monitoring. Based on this scheme, the experimental investigation for beam structures pre and after different levels of damage with distributed long-gage FBG sensors is carried out in this paper. Both static and dynamic macro-strain distributions throughout the beams are obtained under various controlled loading tests. By using static measurements, stiffness estimations are implemented. Moreover, two-level vibration based method is also utilized for damage detection using modal parameters from dynamic macro-strain responses. The comparison of identified damages with the exact set ones has verified the applicability and effectiveness of distributed long-gage strain sensors for damage detection and structural identification.