Fiber Optics Technique for Quality Control and Monitoring of FRP Installations

Synopsis: Advantages such as light weight, high mechanical properties and resistance to aggressive and chemical agents, non invasive installation, low tooling and machinery costs, possibility to repair the structure without interrupting its use have determined great expectation on Fiber Reinforced Polymer (FRP) composites for the strengthening of civil structures. However, their diffusion is often limited by the lack of procedures and methods to assess the quality of installations. The main focus of this paper is to present a non destructive methodology based on a fiber optic refractometer for the quality control of FRP wet lay-up systems. After summarizing the basic parameters necessary for monitoring the cure reaction and introducing the principles of the proposed technique, some preliminary experimental tests are discussed. The analysis of laboratory outcomes allows identifying the aspects that need further research before the proposed technique can be implemented as a field tool for quality assessment of FRP installations.