A Study on Effect of Inhibitors and Concrete Surface Coatings on Corrosion Performance of Rebar in RC Specimens

Abstract

Corrosion is a major economic and safety risk in the construction industry, costing 3-4% of GDP annually. Advances in corrosion science and technology have led to development of corrosion-resistant materials, protective coatings, and corrosion inhibitors. These techniques can reduce infrastructure impact, increase structural durability, and improve sustainability. Shifting towards green inhibitors is crucial for sustainability. newlineThis study examines the impact of chemical and green inhibitors and suface coating on chloride-induced corrosion of reinforcing steel in concrete, evaluating their compressive strength, performance, and dosage optimization, and predicting service life under aggressive exposure conditions. The study systematically investigates the influence of chemical inhibitors (benzotriazole, Sodium Molybdate Dihydrate) and green inhibitors (Calotropis Gigantea and Azadirachta Indica) on the corrosion performance of rebar in simulated concrete pore solutions and contaminated concrete. The experimental work is organized into four series. The first series employs electrochemical methods to assess the inhibitory capacity of organic and inorganic inhibitors in simulated concrete pore solutions over a 150-day exposure period. Azadirachta indica and Calotropis gigantea leaf extracts were the inhibitors used in this research. A chemical inhibitor called benzotriazole and Sodium molybdate Dyhydrate were used to compare the performance of these organic inhibitors. In simulated concrete pore (SCP) solution, organic and inorganic inhibitor concentrations are assessed using electrochemical methods to provide optimum inhibitory capacity. The main objective of the present study was to investigate the effect of organic inhibitor on the corrosion of Thermo Mechanical Treated (TMT) rebar under chloride exposure. This work addresses the evaluation of corrosion resistance of the inhibitors in a simulated concrete pore solution over an exposure period of 150 days and in concrete. newlineThe second series evaluates the corrosion re