Carbonation in reinforced concrete is one of the most common forms of deterioration of structures. It is the reaction of carbon dioxide in the environment with the calcium hydroxide in the cement paste. Due to carbonation, the protective oxide layer surrounding the structure's reinforcing steel breaks down and corrosion or rusting starts. Deterioration is much faster in structures such as bridges which are associated with the ingress of water and freeze/thaw cycling. Carbon dioxide from the atmosphere reacts with the concrete in these structures, leading to a loss of alkalinity and subsequent corrosion of the reinforcing steel. Once the concrete is rusting, concrete starts to stall and falls off leaving an open passage for contaminants to easily penetrate the concrete. The structural integrity of bridges can be compromised until it is protected with an anti-carbonation protective coating.

Anti-carbonation protective coatings protect bridges against the ingress of carbon dioxide and water, whilst allowing damp substrates to breathe without blistering. They protect concrete from carbonation by acting as a carbon dioxide barrier.

MC-Bauchemie is one of the specialist manufacturers and suppliers of anti-carbonation coating products in India. In this article we have focused on a project wherein their anti-carbonation protective products were used to meet the subsequent carbonation challenges in a bridge. Atal Setu Project [which was earlier known as Mandovi Bridge], in Goa, India is the project in focus. The surface protection work of the bridge was executed by using a range of MC-Bauchemie anti-carbonation protective coating products.