CARBONATION AND WETTING OF Ca/Si 0.83 AND 1.5 SYNTHETIC C-S-H
Keywords:
C-S-H carbonation, in-situ monitoring, kinetics, low-calcium C-S-H, high-calcium C-S-HAbstract
This study explores the kinetics of C-S-H carbonation using X-ray diffraction and ATR infrared spectroscopy. It reveals that 1.5 C-S-H exhibits enhanced carbonation due to increased calcium availability, resulting in faster reactions and the persistence of vaterite, even under atmospheric conditions. Despite the presence of portlandite, carbonation in 1.5 C-S-H occurs rapidly, attributed to its higher surface area. Notable changes in Q2 and the formation of silica gel were observed during carbonation. The developed in-situ monitoring method effectively tracks carbonation over 20 hours, offering valuable insights into C-S-H reactivity and structural changes in cementitious materials exposed to CO2.
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