CARBONATION AND WETTING OF Ca/Si 0.83 AND 1.5 SYNTHETIC C-S-H

Authors

  • Monique Lunardi USP
  • Thiago Ricardo Santos Nobre
  • Vanderley Moacyr John

Keywords:

C-S-H carbonation, in-situ monitoring, kinetics, low-calcium C-S-H, high-calcium C-S-H

Abstract

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.

References

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Published

2024-01-15

How to Cite

Lunardi, M., Santos Nobre, T. R. ., & John, V. M. . (2024). CARBONATION AND WETTING OF Ca/Si 0.83 AND 1.5 SYNTHETIC C-S-H. SIMPÓSIO BRASILEIRO DE CIÊNCIA DO CIMENTO, 1(00), 1–5. Retrieved from https://eventos.antac.org.br/index.php/sbcc/article/view/3716

Issue

Section

Descarbonatação da indústria cimentícia