Flexural retrofit of RC beams using CFRP laminates

Abstract

RC structural members have to be retrofitted to comply with the revised codal provisions and changes in functionality of structures. This study aims to investigate the behaviour of prototype RC beams having high shear span ratio externally bonded with CFRP laminates. Four-point bending tests were conducted up to failure of the specimens. The applied load, deflection, strain in concrete, steel reinforcements and CFRP laminate were measured during the testing. The retrofitted specimens showed an increase in ultimate load carrying capacity and stiffness up to 53% and 61% respectively. The retrofitted specimens failed by interfacial crack induced debonding failure mode at a strain of 25% of CFRP laminate's rupture strain. This study concludes that CFRP laminates are to be anchored on RC beams along with bonding using adhesives.