There is an increasing concern about the high carbon dioxide emission associated with the construction industry as the utilization of cement-based materials emits enormous amounts of carbon dioxide into the atmosphere. Sustainable concrete development can be achieved by CO2 sequestration through accelerated carbonation early. It can improve the crystallinity of carbonates during the hydration of cementitious materials. It not only stores CO2 in the thermodynamically stable form of carbonates but also contributes to increasing strength and microstructure densification. These properties enhance concrete durability.
Moreover, CO2 sequestration through carbonation may consume less energy and water than traditional moist curing techniques. A shorter curing time is expected to achieve desired properties than traditional moist curing. However, it should be noted that carbonation curing will consume calcium hydroxide and lower the pH of the pore solution. This may induce de-passivation of the oxidation layer on the surface of steel reinforcement. Overexposure to carbonation curing also leads to the decomposition of C-S-H, thus decreasing the strength.
Therefore, our research goals are to determine carbonation curing strategies; investigate the microstructure development; and evaluate the mechanical, durability, and CO2 binding capacity of different cementitious systems under carbonation curing.