Bridge monitoring by distributed strain measurement using a time-domain Brillouin sensing system

Abstract

We report the results of a load test performed on a road-bridge. In particular, the tests were performed by a portable prototype based on stimulated Brillouin scattering (SBS) in optical fibers. The optical fiber sensor, previously attached along the steel beam, was able to provide the strain profile along the structure, with a spatial resolution of 3 m and a strain accuracy of ±20 με. A comparison with finite-elements-method simulations, as well as with data collected by vibrating wire strain gauges, permitted to confirm the validity of the SBS-based approach in monitoring the deformation of large structures. © 2011 Springer Science+Business Media B.V.