A new approach of shear connectors to delay debonding of CFRP laminates used for shear strengthening of RC beams

Abstract

Shear strengthening of RC beam with adhesively bonded carbon fiber reinforced-polymer (CFRP) laminates is becoming both environmentally and economically more preferable than replacement. However, the early separation of these plated stripes was the most critical failure which leads to prevent reaching the full capacity required from the strengthening. This study aims to present a new method to prevent debonding failure of CFRP laminates adhesively glued to concrete surface using embedded connectors to enhance the interfacial bond strength. Therefore, steel bar and adhesive connectors were fabricated and used at the interface of the bonded CFRP laminates. Five beam specimens including one control beam were tested to investigate the effects of the connectors to prevent or delay the premature debonding of the EB CFRP laminates. The experimental results showed that both steel and adhesive connectors completely prevented premature debonding failure of CFRP shear strip and allowed the beams to fail by flexure with full ductility and strength. Steel and adhesive connectors would enhance 33% and 38% failure loads respectively as compared to strengthened beam without connectors. © 2017 Trans Tech Publications, Switzerland.