Comparative analysis of performance of portland cement blended with nanosilica and silica fume

Abstract

In this paper some physical properties of Colombian Portland cement type III replaced with nanosilica in percentages of 1, 3, 5 and 10% were evaluated. Main determined properties were fluidity, normal consistency, setting times, heat of hydration and compressive strength on pastes and mortars. It was made also a comparative analysis with samples substituted with commercial silica fume in percentages of 5, 10 and 15%. Results showed that the nanosilica from 5% beginning to have a major positive influence on the mechanical strength of mortars and with a 10% of substitution improvements in compressive strength up to 120% with respect to the control sample for one day of curing can be achieved. For longer curing time the improvement is decreased slightly, with near 80%, remaining this improvement in strength after 28 days of curing.