Investigation of strain sensors based on fiber Bragg grating used for steelwork

In the past few years, fiber Bragg grating (FBG) sensors have attracted a lot of interest and there were number of studies on the use of FBG sensors to detect the strain of steelworks. This paper describes the strain sensors based on FBG with different package used for steelwork. Strain distribution of the steelwork is predicted through Finite element analysis. Bare FBG, FBG sensor packaged with steel sheet and resistance strain gauges are set on the same specified location of steel specimen, and load is added on the steelwork by rally machine. Strain values of the steel specimen can be caught by three kinds of sensors when load is stabilized. Then the load added on the steelwork is changed from 0KN to 50KN and back to 0KN, meanwhile the values of strain are recorded respectively. Results of three sensors are compared mutually and are all close to theoretical values provided by FEA.