Keywords: wet-dry cycle
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A study on the application of accelerated carbonation cement paste powder by wet-dry cycle technique to supplementary cementitious material
Carbonated recycled concrete paste can serve as a supplementary cementitious material (SCM) with pozzolanic properties from alumina-silica gel. Additionally, since it contains fine particles of calcium carbonate, it is expected to enhance concrete performance through its filling effect when used as SCM. Previous studies have shown that the wet-dry cycle method promotes CO₂ absorption and increases the porosity of concrete paste. Based on this, the study aims to efficiently absorb CO₂ using waste concrete paste through the wet-dry cycle method and seeks to recycle resources and enhance concrete performance by reusing the carbonation products as SCM.
Dayoung OH (researchmap.jp, researchgate.net, scholar.google.com), and Ryoma KITAGAKI
The Taisei Foundation 2025.4~2026.3
Effect of Wet−dry Cycles and Water-to-cement Ratios on Cement Paste Carbonation
Cement production consumes a significant amount of energy and releases CO₂ emissions, while concrete waste can potentially reabsorb CO₂. This study examined the effect of relative humidity (especially wet-dry cycles) on the carbonation of hardened cement pastes. Wet–dry cycles increased porosity and caused the decomposition of calcium silicate hydrate (C-S-H) through shrinkage and deformation during drying. As a result, the highest CO₂ absorption in the wet-dry cycle sample was twice that of the constant RH. Additionally, the amount of CO₂ captured during the 28-day wet-dry cycle accounted for about 17% of the annual CO₂ emissions from cement production.
Zhiwei Zhao, Dayoung Oh (researchmap.jp, researchgate.net, scholar.google.com), Ryoma Kitagaki, Tianlong Zheng, and Ippei Maruyama