A Study on Sensing Properties of Nickel Protected and Embedded Fiber Bragg Grating Based on Stress Analysis

The Fiber Bragg Grating (FBG) sensor was embedded in cement mortar after it was nickel electroplating protected. The stresses on the embedded FBG under varied temperature were analyzed. The temperature sensitivity of embedded FBG was achieved in theory base on stress analysis and verified by experiment. The temperature sensitivity of embedded FBG is 19.2188 pm/°C in theory, while the experiment result is 20.688 pm/°C. A finite element analysis software (ANSYS) was used to simulate the stresses on the embedded FBG. The results of theoretical analysis match the ones from experiments and simulations very well.