THE MECHANISM OF THE HYDRATION OF TRICALCIUM SILICATE AND β-DICALCIUM SILICATE

Abstract

Labelled tricalcium silicate, prepared by heating together inactive dicalcium silicate and lime labelled with Ca45 has been hydrated in saturated solutions of calcium hydroxide at 21 °C. Parallel studies of the rate of liberation of lime due to hydrolysis and the coincident appearance of Ca45 in the solution indicate that the CaO:SiO2 ratio in the precipitated hydrated silicate is 3:2. A similar result is obtained when inactive tricalcium silicate is hydrated in an active lime solution. Comparable studies on the hydrolysis of labelled β-dicalcium silicate indicate the formation of a product with the same CaO:SiO2 ratio. The method appears to have rather general application.