Performance and Health Monitoring of civil structures and infrastructure using long-gauge and distributed Fiber Optic Sensors

Construction, preservation, maintenance, and renewal of sustainable and resilient civil structures and infrastructure represent important challenges for a 21st-century society. Structural Health Monitoring (SHM) is a novel approach which can successfully assist in meeting these challenges by providing actionable, quasi-real-time information regarding structural performance and health condition. Fibre Optic Sensors (FOS) have been deployed in SHM applications since the 1990's, and besides proven long-term performance, they also offer two unprecedented sensor types for practical applications in strain-based SHM: long-gauge stain sensors and truly distributed strain sensors. These FOS enable two paradigm-changing SHM approaches, respectively: global structural monitoring and integrity monitoring. The aim of this paper is to briefly summarize physical principles of FOS, present commercially available long-gauge and distributed FOS, introduce theory behind structural monitoring and integrity monitoring enabled by FOS, and demonstrate the effectiveness of the approaches through real-life application on the Streicker Bridge.