Accelerated corrosion and repair of reinforced concrete columns using carbon fibre reinforced polymer sheets

An experimental study on the simulation of corrosion in large-scale reinforced concrete columns and their repair using carbon fibre reinforced polymer (CFRP) sheets is presented. Seven columns were subjected to an accelerated corrosion regime, wrapped using CFRP sheets, then tested to structural failure and (or) subjected to further post-repair accelerated corrosion, monitoring, and testing. Accelerated corrosion was achieved by adding sodium chloride to the mixing water, applying a current to the reinforcement cage, and subjecting the specimens to cyclic wetting and drying. Results showed that the CFRP repair greatly improved the strength of the repaired member and retarded the rate of post-repair corrosion. Moreover, subjecting the repaired column to extensive, post-repair corrosion resulted in no loss of strength or stiffness and only a slight reduction in the ductility of the repaired member.Key words: accelerated corrosion, carbon fibre reinforced polymer, composites, corrosion damage, corrosion rate, external confinement, reinforced concrete columns.