Bridge displacement monitoring based on fiber Bragg grating-differential settlement measurement sensors

Bridge managers are always looking for an easy way to measure vertical displacements of bridges. With the advancement of fiber–optic technologies, Fiber Bragg Grating (FBG) sensors are more commonly used in structural health monitoring due to their outstanding advantages including multiplexing capability as well as high resolution and accuracy. In this study, FBG–Differential Settlement Measurement (DSM) sensors, connected by hydrostatic leveling system of communicating vessels, were used for the displacement measurements along a large–scale Prestressed Concrete I (PCI) beam. The measured displacements matched well with the corresponding experimental values using Linear Variable Differential Transformers (LVDT).