Structural Health Monitoring System Based on FBG Sensor and Its Application

In this paper, the method of structural evaluation using structural health monitoring data in Japan and the status quo of the processing and analysis technique of measured data are briefly introduced. A distributed monitoring system and its applications for flexural structures proposed by author are illustrated. The method is based on a series of lab experiments and theoretical studies for the utilities of distributed long-gage fiber Bragg grating (FBG) sensor system by author's research group, combined with monitoring data analysis software SforD, the structure health monitoring for bridges can be implemented by means of the distributed strain measurement. From the measured distributed dynamic strain along the longitudinal direction of the bridge, the deflection distribution, the structure dynamic characteristics (such as nature frequency and modes), the information of load and the bridge damage detection can be obtained, and the structure evaluation can be performed by those parameters. The actual survey for several old under-use bridges in Japan proved effectiveness of this distributed monitoring system. This paper can provide multi-functional structural health monitoring and detection solutions for the construction of smart cities and smart structures.