| An overview of in-fibre Bragg gratings is given, as well as a discussion of the sensors themselves. The different sensor application techniques such as surface application, embeddment in fibre reinforced plastics, and embeddment in concrete are described. The other types of fibre optic sensors discussed include Fabry-Perot sensors, Measurand sensors, Con-tech sensors, and Microbend sensors. Application of sensors to a structure for the extraction of data is a form of nondestructive testing. Other methods of nondestructive testing including foil gauges applied to the surface of structures, vibrating wire and embedment gauges embedded in concrete, and acoustic emissions sensors are also discussed.; The fibre optic Bragg grating sensors used in this research were demodulated using the FLS-3000 grating strain indicator. An overview of the principles of operation of the FLS-3000 is given, as well as discussions on temperature compensation, remote monitoring, data acquisition, and problems with the instrument. Also discussed are the StressNet and SCXI data acquisition systems used for the monitoring of conventional foil gauges.; A series of laboratory tests are reported in this thesis including tests of steel straps, an aluminum test specimen, Model Deck 2, Model Deck 3, and a NEFMAC sample; in all tests strain was measured using fibre Bragg grating sensors and compared to values from a conventional gauge. (Abstract shortened by UMI.)... |
