Optical Fiber Relative Humidity Sensor Based on a FBG with a Di-Ureasil Coating
authors Correia, SFH; Antunes, P; Pecoraro, E; Lima, PP; Varum, H; Carlos, LD; Ferreira, RAS; Andre, PS
nationality International
journal SENSORS
author keywords fiber Bragg gratings; optical fiber sensors; relative humidity; organo-silica hybrid; structure health monitoring
abstract In 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.
publisher MDPI AG
issn 1424-8220
year published 2012
volume 12
issue 7
beginning page 8847
ending page 8860
digital object identifier (doi) 10.3390/s120708847
web of science category Chemistry, Analytical; Electrochemistry; Instruments & Instrumentation
subject category Chemistry; Electrochemistry; Instruments & Instrumentation
unique article identifier WOS:000306796500024