Microstructural Study of Hydration Reactions of a Fly Ash-Belite Cement

The evolution of the microstructure of a hydrated fly ash-belite cement (HFABC) has been studied during a period of 90 days after mixing. The cement was synthesized from a mixture of fly ash (ASTM Class F), lime and water by a hydrothermal procedure. The microstructure characterization at different times was followed by mercury intrusion porosimetry (MIP), scanning electron microscopy (SEM) and EDS, X-ray diffraction (XRD), thermogravimetry (TG) and analytical techniques. Besides, the compressive strength was determined and correlated to the microstructure characteristics. The pore solution was expressed and analyzed at different periods of the hydration reaction.