Externally Bonded Fiber-Reinforced Polymer for Rehabilitation of Corrosion Damaged Concrete Beams

Abstract

This paper reports the results of an experimental program designed to provide a realistic assessment of the potential of using fiber-reinforced polymer (FRP) materials in the repair and strengthening of reinforced concrete (RC) flexural members. The experimental program included seven RC flexural beams, 270-by-400 mm in cross section and 4,350 mm in length. Four of the seven RC beams were reinforced externally with one or two layers of carbon FRP (CFRP) composite. Variables considered included state of damage (damaged versus undamaged) and loading condition during bonding (loaded versus unloaded). Damage was introduced in four of the seven RC beams using an accelerated corrosion technique developed at the University of Toronto. Test results revealed that it is necessary to consider the effects of corrosion- and load-induced damage as well as sustained load on the load-carrying and deflection capacities of externally reinforced flexural members. Furthermore, it is concluded that it is possible to achieve adequate corrosion repair with externally bonded CFRP and minimal intervention. In particular, results showed that it is important to optimize CFRP layout to balance strength recovery with control of faulting and splitting, which could lead to premature member failure.