On the processing and evaluation of pultruded smart composites

Abstract

The use of the pultrusion process for the manufacture of fiber reinforced polymer (FRP) composites with embedded fiber optic sensors are discussed. The specific application is the use of smart composite reinforcements for strain monitoring in innovative bridges and structures. The Bragg Grating and Fabry Perot fiber optic sensors are successfully embedded during the pultrusion of FRP rods. The behavior of optic sensors during pultrusion was assessed, and the effect of the embedment of optical fibers and their surface coatings on the mechanical properties of the composite was investigated. Monitoring of the output of embedded fiber optic strain sensors during the pultrusion of composite rods may provide useful information about the formation of process-induced strains within the composite. To verify the operation of the optic sensors embedded in the smart pultruded tendons, mechanical tests were conducted and the output of the fiber optic sensors was compared to that of an extensometer during quasi-static and cyclic tensile tests.