ABSTRACT
The use of Optical Backscatter Reflectometer (OBR) as a distributed fiber optic system to measure strain and detect cracking in concrete structures is investigated. The cooling tower of a power plant was monitored using the OBR sensor system. Brillouin systems have been used to monitor piles and other geotechnical works and reinforced concrete bridges. Due to the roughness of the concrete surface and the material heterogeneity, the application to concrete civil engineering structures has been limited. In 2010, a bridge load test was conducted in order to investigate once again the effectiveness of the OBR technology monitoring system in a concrete structure. Important points such as the geometrical non linearity and the material non linearity, durability, possible settlements, must be considered in order to obtain global information about the behavior of the structure. In order to facilitate the application of the optical fiber it was necessary to prepare the concrete surface due to its roughness.
