Autonomous structural monitoring using fiber Bragg grating

Abstract

An autonomous structural monitoring system (ASMS) is a functional unit capable of sensing and assessing the health of a structure and reporting the status to a maintenance center for appropriate action. In this paper, such a system is presented. The main components of an ASMA are: power meter, broadband optical source, twin-core fiber, spring, fiber Bragg grating (FBG), and a wired or wireless transmitter. It has been shown that FBG has applications in strain and temperature measurements. A newly developed sensing head has been built and tested which consists of a spring and FBG and is used to sense displacement or cracks in various structures such as buildings, bridges, pipelines, ships..., etc. Here, the new sensing head is adapted to integrate the functions of the sensing head FBG and spring with an optical coupler and twin-core fiber into a displacement sensor unit. The proposed ASMS can be tuned for different structures and specifications.