Optical sensor networks for structural health monitoring of canton tower

Abstract

Structural health monitoring (SHM) systems are crucial for modem civil structures such as high-rise buildings and long-span bridges in terms of operational safety and economical aspects. Fiber Bragg gratings (FBGs) sensing system is one of the optical fiber sensory systems with maturity in fabrication, comprehensive in functionality and effective in implementation. SHM systems based on FBG sensor networks are becoming popular in civil applications. FBG sensor also possesses salient features such as light weight, small size. immunity to electromagnetic interference, corrosion resistance, multiplexing capability over a single fiber for measuring different parameters such as strain, temperature, acceleration, wind speed, etc. These distinctive advantages make FBG sensor system a good candidate to serve as an integral part of a long-term SHM system. The small size (Le. diameter of optical fiber with 125J.1m) of FBG sensors permit them to be used to monitor/measure even scaled-down model of civil structures. In this paper, a SHM system for the 61O-m tall Canton Tower in Guangzhou, China integrates both in-construction and inservice monitoring, comprising about 800 sensors with over 200 FBG based sensors was successfully installed.