Mineralogical-microscopical study of cement paste/mortar containing fly ash

摘要

Cement - fly ash (Type F) pastes hydrated at different ages were studied by scanning electron microscopy/energy dispersive X-ray analysis (SEM/EDXA), X-ray diffraction (XRD) and thermal analyses (TG/DTA). Methods of study are described and compared based on the results. Fly ash - cement replacement ratios were 0, 30 and 60 % by weight of the binder. A comparative study was conducted to verify the effect of gypsum (10 % by weight of fly ash) on the hydration process of the fly ash. Data including mineralogical composition of the pastes and degree of hydration at different ages are recorded in detail. In addition to the study on the pastes, cement-fly ash mortars of long term water curing (> 90 days) were examined microscopically by both SEM/EDEXA and backscattered image. 55 refs, 57 figs