Retrofit of Shear Critical R.C. Beams with Carbon Fiber Reinforced Polymers (CFRP)

Abstract

This paper presents results of an experimental investigation involving eighttests on 1800mm long reinforced concrete (RC) beams strengthened in shear withexternally bolted carbon fiber reinforced polymer (CFRP) composites. The overallobjective of this study was to investigate the shear performance and failure modesof RC beams strengthened with externally fixed carbon FRP (CFRP) manufacturedU-warp strips and the specific goal was to keep the CFRP strips working till thebeam reaches its flexural failure because in most of the previous researches theCFRPs debonded from the concrete surface and the failure (separation) happenedin the concrete. The variables investigated within this program included: CFRPspacing and number of CFRP layers. The experimental results indicated that thecontribution of externally fixed CFRP strips to the shear capacity is significant anddepends on the variables investigated. In all the beam specimens (with endanchorage) the debonding was not observed.