HYDRATION CHARACTERISTIC OF LIME - SILICA FUME PASTES

The hydration of two calcium hydroxide - silica fume mixtures was stud ied at 25-degrees-C, these are Mix I and Mix II with molar lime/silica ratios of 1 and 1.7, respectively. The free lime, free silica and che mically combined water contents were determined at various time of hyd ration from which the molar CaO/SiO2 ratioS Of the formed calcium sili cate hydrate, C-S-H, were calculated. The results indicated that hydra tion takes place in six steps where C-S-H (I) is formed at early stage s of hydration, for Mix I, while for Mix II formation of C-S-H (I) and C-S-H (II) were detected by X-ray diffraction analysis and differenti al thermal analysis.