ASSESSMENT OF FIBER OPTIC SENSOR TECHNOLOGIES FOR REAL-TIME STRUCTURAL HEALTH MONITORING OF CIVIL ENGINEERING INFRASTRUCTURE

Abstract

Structural health monitoring (SHM) has emerged as a critical strategy for ensuring the safety, durability, and sustainability of civil engineering infrastructure such as bridges, dams, tunnels, and high-rise buildings. Traditional inspection approaches, including visual assessment and conventional electrical sensors, often fail to provide continuous and high-precision monitoring of structural conditions. In recent decades, fiber optic sensor (FOS) technologies have gained considerable attention due to their high sensitivity, immunity to electromagnetic interference, long-distance sensing capability, and ability to operate in harsh environments. This study assesses the role and effectiveness of fiber optic sensor technologies in real-time structural health monitoring of civil engineering infrastructure. The paper reviews the principles of optical sensing, major fiber optic sensing technologies including Fiber Bragg Grating (FBG), interferometric sensors, and distributed optical fiber sensors (DOFS), and their performance in monitoring strain, temperature, vibration, and crack propagation in civil structures. The study further evaluates their integration with data acquisition systems and emerging technologies such as Internet of Things (IoT), artificial intelligence, and machine learning for predictive infrastructure maintenance.

Results from various experimental and field investigations demonstrate that fiber optic sensors provide high spatial resolution, real-time monitoring capability, and long-term stability compared with conventional strain gauges and electrical sensors. These technologies have been successfully applied in bridges, tunnels, pipelines, offshore platforms, and smart buildings. The findings highlight that distributed fiber optic sensing technologies, particularly those based on Rayleigh, Brillouin, and Raman scattering, enable continuous monitoring along several kilometers of infrastructure, providing early detection of structural anomalies. However, challenges remain related to installation complexity, calibration, signal interpretation, and cost of deployment. The study concludes that fiber optic sensor technology represents one of the most promising solutions for next-generation smart infrastructure monitoring systems, supporting resilient and sustainable infrastructure development.