Effect of corrosion on bond strength of steel and non-metallic reinforcement

Research attempts on the effect of environmental corrosion on bond between steel bars and concrete, report considerable losses of bond strength. Alternative solutions to the corrosion problem include the use of non‐metallic reinforcement. In this paper the effects of environmental corrosion (through accelerated carbonation) on the bond properties of fiber reinforced polymer (FRP) bars with the surrounding concrete are investigated. The work presented is part of an extensive project addressing the durability of FRP in concrete 1. It was found out that, in contrast to what is generally believed, concrete alkalinity does not have a major impact on the durability of FRP bar and its bond strength. The expected bond deterioration due to carbonation is more than compensated by the increase in compressive strength due to time and carbonation, contrary to the case when steel reinforcement is used.