Optical fibers, serving as sensors and data conduit, are particularly relevant for long-term health monitoring of civil structures. Nevertheless, many challenges associated with the on-site application of such sensors have to be solved, these are mainly related to the application methodology.
The objective of this current research is to assess the feasibility and reliability of strain measurements by utilising FBG (Fiber Bragg Grating) optical sensors embedded in two types of FRP (Fiber Reinforced Plastic) packaging. The first device consists of an FRP reinforcing sheet with embedded FBG sensor, conceived for external application on the structural element surface. The FRP packaging of the second device consists of a FRP rebar, conceived for internal or Near Surface Mounted (NSM) applications. These two FRP packages provide the optical fiber with the necessary protection against accidental damage during handling and installation. The mechanical characteristics of the packaging material allow the use of the device for structural reinforcing purpose as well.
The paper discusses the various steps in the development of the technology set-up, the physical and the mechanical testing and the in situ validation for the two devices.
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