Hydration and performance evolution of belite–ye'elimite–ferrite cement

The hydration, microstructure and mechanical performance of calcium belite–ye'elimite–ferrite cements were investigated by a multi-method approach. The early hydration was found to be dominated by the reaction of ye'elimite, calcium sulfate and calcium aluminate phases. The hydrates formed were mainly ettringite and an X-ray diffraction (XRD)-amorphous phase composed of CAH 10 and alumina hydroxide. The later reaction of belite resulted in the formation of strätlingite and phase transformations mainly occurring within the XRD-amorphous phases. These processes modified the initial microstructure and the resulting mechanical performance. The micromechanical modelling used in this work contributes to understanding of the performance origin and reveals the role of individual hydrates in volume filling and strength evolution.