Keywords: nondestructive testing, NDT, fibre optic sensors, performance evaluation, interfacial strain measurement, long–term monitoring, structural monitoring, concrete structures
Fibre optic sensors as a non–destructive tool for structural monitoring
Structural monitoring is a diagnostic tool for detection of defects/damages and for scheduling maintenance operations. It is essential to determine the safety of the structures by Non–Destructive Testing (NDT) for evaluation of strength/integrity. This assessment is required for the repair, rehabilitation and life extension of the structure. Fibre Optic Sensors (FOS) are attractive sensing devices as an NDT tool, given their small size, light weight, immunity to electrical noise and electromagnetic interference. Optical fibres offer the possibility of embedding in cement/concrete without affecting their performance. Sensors can also be surface mounted on concrete/steel members. There are challenging problems/issues in applying FOS for concrete structures. Systematic studies on FOS have been carried out in the laboratory to solve the issues/problems. In this paper, details of the laboratory studies carried out in solving some of the technical challenges and issues in fibre optic sensing technology are covered.