Quantatative determination of pozzolanas in hydrated systems of cement or Ca(OH)2 with fly ash or silica fume

Abstract A selective dissolution method using a slightly modified picric acid-methanol-water solution procedure was found to be adequate for the quantitative determination of unhydrated fly ash and silica fume in hydrated systems of cement-fly ash and cement-silica fume, respectively. The extent of hydration of fly ash and silica fume in various paste mixtures has been calculated. The hydration products and the residue composition were examined by both X-ray diffraction and energy-dispersive X-ray analysis and their morphologies were observed under an SEM.