Improving corrosion resistance of reinforced concrete structures using carbon fibre reinforced polymer

Abstract: Corrosion of steel is regarded as one of the most important issues for the durability of reinforced concrete (RC) structures, as corrosion can induce the serviceability decrease, bond strength dropping, steel properties reduction, and longitudinal cracking in RC structures. Carbon fiber reinforced polymer (CFRP) has been applied in RC structures for strengthening existing structures, due to such benefits in high flexural strength, reducing drying shrinkage and improving tensile strength etc.. However, limited researches related to the corrosion of RC structures wrapped by CFRP could be identified. This study aims to improve corrosion resistance of reinforced concrete structure using CFRP. The steel corrosion diffusion of RC structures with different CFRP wrapped ratios, mainly in the corrosion initiation stage, was investigated in 3.5% NaCl solution. The monitoring techniques of the open circuit potential (OCP), linear polarized resistance (LPR) and electrochemical impedance spectroscopy (EIS) were employed to monitor and assess the corrosion behavior of RC specimens. The experimental results indicated that CFRP could delay the corrosion diffusion of RC elements. The study has benefits in enhancing the durability of RC structures using CFRP for strengthening existing civil engineering structures.