Effect of the mechanical activation of nepheline concentrate on its binding properties in mixed cements

Binding properties of a Portland cement-nepheline-water formulation were studied in relation to its nepheline content by using a preliminary mechanical activation. A thermal analysis was used to estimate the hydration rate of cement phases in the system under study. The accelerating role of nepheline in hardening of mechanically activated Portland cement-nepheline formulations was revealed and found to be more pronounced in early stages. The gain in the strength of the cement stone was analyzed in relation to the formulation composition and hardening duration.