Quantitative calculation of hydration products for binary slag-Portland cement system

Abstract

The reaction models and the quantitative calculation on the volume fraction of hydration products for binary ground granulated blast-furnace slag (GGBFS) cement system are presented, in which two important factors are taken into account, i e, the reactivity of GGBFS influenced by its chemical compositions and the partial replacement of aluminum phase in calcium silicate hydrate (C-S-H) gel. A simplified treatment is further suggested towards the quantification. In particular, when the replacement level of GGBFS is lower than 70%, the ratio of calcium over silica (C/S) is set at 1.5 or at 1.2 otherwise. The validity of the proposed model is addressed in terms of the contents of calcium Portlandite and non-evaporable water.

Keywords

Portland cement / GGBFS / reaction model / hydration product

References

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