Infrastructure Optics

An overall strategy in infrastructure health monitoring systems is given through the concept of Infrastructure Optics. The focus is to design and build optical devices and systems, primarily fiber optic communication technology, for health monitoring of infrastructure. Recent developments in the use of Optical Frequency Domain Reflectometry (OFDR) to demodulate Fiber Bragg Grating Arrays (FBGA) have shown promise in its use in infrastructure health monitoring systems. However, the number of papers on the simulation and characteristics of FBGA using OFDR demodulation for health monitoring purposes is not great. In this paper, a FBGA is simulated using OFDR demodulation technique to extract strain information from a simulated cantilever beam host. The structure is first simulated using a Finite Element Model (FEM) to determine displacement and strain response, and the results are used as inputs to the FBGA. An OFDR program then demodulates the array to extract the strain response of the cantilever beam. The characteristics of OFDR and FBGA system is analyzed and compared to actual FEM results.