Fundamental understanding of carbonation curing and durability of carbonation-cured cement-based composites: A review.

• The process of carbonation curing and related chemical reactions are reviewed. • Different strategies of carbonation curing optimization are elaborated. • Matrix of cement-based composite is densified, and matrix/fiber interface is improved by carbonation curing. • Durability in different aspects are enhanced by carbonation curing. • Corrosion and alkali-silica reaction potential by carbonation curing are discussed. To tackle the rising CO 2 concentration in atmosphere, technologies of carbon sequestration are emerging. As one of these technologies, carbonation curing of cement-based composite at early age shows a great potential because its wide application and benefits to provide cement-based composite with enhanced mechanical properties and durability. However, carbonation curing is mostly investigated on lab-scale, due to two main challenges that should be addressed before it can be widely applied for industrial-scale production: (1) CO 2 sequestration rate is still low, which is around 20 %–50 % of the theoretical potential because of the limitation of CO 2 diffusion into matrix during the carbonation curing; and (2) the effect carbonation curing on the durability of cement-based composites and the underlying mechanisms remains unclear, especially for some critical aspects such as alkali-silica reaction, corrosion, and sulfate attack. Therefore, this paper focuses on discussing: (1) factors affecting CO 2 sequestration in cement-based composite during each stage of carbonation curing and the optimization methods of carbonation curing for high CO 2 sequestration rate without mitigating mechanical properties and durability, and (2) effects of carbonation curing on different aspects of durability and the corresponding mechanisms. Based on the review, future studies on addressing current challenges are inspired to comprehend and promote the carbon sequestration by carbonation curing of cement-based composites. [ABSTRACT FROM AUTHOR]