A DISTRIBUTED STRAIN SENSOR FOR BRIDGE MONITORING

To facilitate an efficient bridge management system, knowledge is required of the state of health of bridge structures. It has been shown that Electrical Time Domain Reflectometry (ETDR) distributed strain sensors possess great potential for the application of on-line health monitoring of large concrete civil structures. The ETDR strain sensing technique can not only monitor structural response but also can detect crack damage and pinpoint its locations. The full potential of the ETDR strain sensing method needs to be further explored for its practical application for real-world bridge structures. In this project, the effect of various surface treatments for embedded ETDR sensors on sensor signal responses was investigated. Small laboratory-scale bending tests were conducted for reinforced concrete specimens with embedded ETDR sensors with various surface treatments. The test results showed that the application of interface adhesive agents substantially improved signal response of the embedded ETDR sensor.