Fiber optic monitoring system for prefabricated buildings

Structural health monitoring (SHM) is a crucial aspect of understanding the safety of in-service civil engineering structures. Real-time monitoring offers an effective solution for the timely detection of defects and structural damages, facilitating focused routine maintenance and mitigating the need for costly extraordinary structural repairs. While various technologies have been developed to monitor structural safety, identifying and quantifying anomalies in different materials, many of them exhibit high intrusiveness and sensitivity to electromagnetic interferences. Therefore, a more convenient approach is to implement a sensor monitoring system during the industrial production of pre-cast reinforced concrete (RC) structures. Embedding sensors in pre-cast beams, columns, etc., during construction enables quality control, aiding in the early detection of defects that may compromise load capacity and durability. To address issues related to intrusiveness and electromagnetic interference, the PREFOS research project employs fiber optical systems (FOS), utilizing quasi-distributed Fiber Bragg Grating (FBG) technology sensors. FBG sensors are well-suited for both static and dynamic measurements, allowing for the monitoring of strains, displacements, and temperature variations. This approach ensures that the final precast elements are inherently ready for monitoring at the construction site, eliminating the need for subsequent instrumentation steps.