Hydraulic activity and microstructural characterization of new fly ash–belite cements synthesized at different temperatures

The influence of the synthesis temperature of a new fly ash–belite cement (FABC) on its hydraulic activity and microstructural characteristics is discussed in this work. Three types of FABC were synthesized at 700, 800, and 900 °C after a previous hydrothermal treatment at 200 °C of the fly ash, CaO, and water mixture. The hydraulic activity of the pastes was evaluated during a period of 200 days from mixing through the combined water content, previously determined from thermogravimetric analyses, and the hydration advance degree by x-ray diffraction (XRD). The microstructure characterization of the pastes was studied by scanning electron microscopy (SEM).