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2018.
EFFECT OF NANOSILICA ON EARLY STRENGTH OF CEMENT MORTAR
This paper presents the effect of nanosilica on the early strength of cement mortars. Three series of samples were investigated: one with ordinary Portland cement CEM I 52,5 N and two with siliceous and calcareous fly ashes as a partial cement replacement (25 wt. %). The results reveal that by using small amount of nanosilica (2 and 4 wt. % of binder) water demand of all tested cement pastes increases proportionally to nanosilica content, while the setting time is not significantly influenced. Compared to the reference samples, the addition of 2 % nanosilica increased two-days strengths, while addition of 4 % nanosilica reduced two-days strengths of the mortar samples.