Correia, Sandra F. H.Antunes, PauloPecoraro, Édison [UNESP]Lima, Patricia P.Varum, HumbertoCarlos, Luis D.Ferreira, Rute A. S.Andre, Paulo S.2014-05-202014-05-202012-07-01Sensors. Basel: Mdpi Ag, v. 12, n. 7, p. 8847-8860, 2012.1424-8220http://hdl.handle.net/11449/26170In this work we proposed a relative humidity (RH) sensor based on a Bragg grating written in an optical fiber, associated with a coating of organo-silica hybrid material prepared by the sol-gel method. The organo-silica-based coating has a strong adhesion to the optical fiber and its expansion is reversibly affected by the change in the RH values (15.0-95.0%) of the surrounding environment, allowing an increased sensitivity (22.2 pm/%RH) and durability due to the presence of a siliceous-based inorganic component. The developed sensor was tested in a real structure health monitoring essay, in which the RH inside two concrete blocks with different porosity values was measured over 1 year. The results demonstrated the potential of the proposed optical sensor in the monitoring of civil engineering structures.8847-8860engfiber Bragg gratingsoptical fiber sensorsrelative humidityorgano-silica hybridstructure health monitoringArtigo10.3390/s120708847WOS:000306796500024Acesso abertoWOS000306796500024.pdf5282584912774370000-0002-5049-8797