Effects of accelerating and retarding agents on nucleation and crystal growth of calcium aluminate cement

Abstract

Although calcium aluminate cement (CAC) has been widely used, one of the critical unclear issues in the field of cement chemistry focuses on certain mechanisms that manipulate the rate of cement hydration. A better understanding of hydration provides critical information such that issues, such as setting time, strength gain, and durability, can be better addressed. This study aimed to initially provide theoretical predictions using experimental information on the dissolution, nucleation, and precipitation mechanisms of ions, induction time (tind), interfacial free energy (γ), and the crystal growth mechanism of CAC containing accelerating and retarding agents in microstructural systems. We also aimed to investigate the early-age performance of CAC, including the setting time of pastes and strength development of mortars. Results found that adding accelerating and retarding agents affected the dissolution, nucleation, and precipitation mechanisms of the CAC hydration. This finally affected the phase formation of the final products.