The effect of etching on the performance of FBG-based strain sensor

Cracking is a widely existent issue for any infrastructures that may lead to its advanced failure. In every infrastructure it is important to make sure that the cracks can be detected and monitored earlier in order to avoid any unwanted incident or any deformation of structures. Recently, Fibers Bragg gratings (FBGs) are growing interest in sensing applications such as in aerospace, military, structural monitoring and many others. FBGs are very high accuracy and also high sensitivity. In this paper, FBGs strain sensor is proposed. The effect of etching on the FBG is studied and compared with the non-etched FBG. The sensor sensitivity for non-etched and etched FBG recorded is 1.20 pm/pr and 0.94 pm/pr respectively. It is shown that the sensitivity of the sensor using etched FBG improved 21.6% compared to its counterparts. This sensor is proven suitable for the application of crack sensing in building structure.