On the hydration of Belite-Ye'elimite-Ferrite (BYF) cement pastes: Effect of the water-to-cement ratio and presence of fly ash

Autor(es)

Koga, Guilherme Yuuki ; Albert, Blandine ; Nogueira, Ricardo Pereira

• Tipo de documento: Artigo Científico
• Fonte: CEMENT AND CONCRETE RESEARCH; v. 137, p. 12-pg., 2020-11-01.

Resumo

This work reports the evolution of the phase assemblage, pore solution, porosity, and mechanical resistance of Belite-Ye'elimite-Ferrite (BYF) cement pastes. Different water-to-cement (w/c) ratios were considered and the addition of fly ash (FA) evaluated. The initial 1-day hydration of BYF cement paste was characterized by the ye'elimite hydration accompanied by a pronounced alkalinity increase controlled mainly by the molar ratio of calcium sulfate to ye'elimite. Throughout the 1-year test, the phase assemblages of 0.50 and 0.67 w/c samples were similar, composed of ettringite, AFm, stratlingite, silicious hydrogarnet, and C-S-H. The hydration of the 0.40 w/c cement paste was almost complete within a month. Additions of 25 wt% FA increased the fraction of stratlingite and ettringite without long-term strength losses compared to plain BYF cement paste with the same water-to-binder ratio. Results from different characterization techniques for both liquid and solid phases at early-age (first 24 h) were complemented by thermodynamic calculations. (AU)

• Processo FAPESP: 19/02136-3 - Corrosão de ligas de alta entropia conformadas por spray
• Beneficiário: Alberto Moreira Jorge Junior
• Modalidade de apoio: Auxílio à Pesquisa - Pesquisador Visitante - Internacional