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

Autores

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

Palavras-chave:

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

Resumo

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.

Referências

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MADDALENA, R. et al. Direct synthesis of a solid calcium-silicate-hydrate (C-S-H). Construction and Building Materials, v. 223, p. 554–565, 30 out. 2019.

PHUNG, Q. T. et al. Effect of limestone fillers on microstructure and permeability due to carbonation of cement pastes under controlled CO2 pressure conditions. Construction and Building Materials, v. 82, p. 376–390, 2015.

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Publicado

2024-01-15

Como Citar

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. Recuperado de https://eventos.antac.org.br/index.php/sbcc/article/view/3716

Edição

Seção

Descarbonatação da indústria cimentícia