Influential factors on concrete carbonation: a review

After water, concrete is the most widely used substance on the planet. Carbonation of cementitious materials is an inevitable process through which concrete compositions react with carbon dioxide. Carbonation leads to rebar corrosion in reinforced concrete (RC) structures, reducing structures’ longevity. This process increases cement production, for repair and replacement, which brings about more carbon dioxide emission. Conversely, plain concrete could be one of the materials with the most potential in terms of carbon dioxide storage. Therefore, an understanding of concrete carbonation and the influential parameters on its carbonation is significant. Identifying the effective parameters helps engineers increase RC structures’ carbonation resistance and increase plain concrete capacity as a carbon dioxide capture source, which could be both cost-effective and environmentally friendly. In this review, an attempt has been made to summarise present-day knowledge considering cementitious materials’ carbonation and point out the areas that need more research to be conducted. Influential factors have been categorised comprehensively. Affecting factors have been explained. Environmental conditions, concrete characteristics and construction operation effects have been reviewed. Furthermore, mathematical models for concrete carbonation proposed by different researchers have been examined to investigate influential parameters in the models and their precision in prediction.