Hydration Mechanism of Cement-based Materials with Different Si-rich Mineral Admixtures

Abstract

Early hydration mechanism of cement-based materials with silica fume, nano-SiO₂ and silica sol of different contents was investigated, and the detailed effect of these Si-rich mineral admixtures in three stages of early hydration (NG, I, D) using kinetics model was focused. The results showed that silica fume, nano-SiO₂, and silica sol have significant effect on kinetic parameters n, k ₁, k ₂ and k ₃, the fineness and existing form of SiO₂ particles in these Si-rich mineral admixtures are two important factors to affect the hydration process and on the parameters. Through integrated use of methods of hydration heat-Krstulovic-Dabic Modelsynthetical thermal analysis, data of hydration heat were collected, hydration degree was characterized, as well as the resulting crystallization behavior of early hydration, to build a numerical relationship between parameter n and CH contents that n decreases with increasing CH, and thus, a direct connection between hydration heat release behavior and crystallization behavior has been established.

Keywords

silica fume / nano-SiO₂ / silica sol / hydration kinetics model / early hydration / CH content

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