HYDRATION CHARACTERISTICS OF BETA/CIS IN THE PRESENCE OF SOME POZZOLANIC MATERIALS

There are four polymorphs for dicalcium silicate designated as alpha, alpha, beta and gamma. The gamma form is essentially non-hydraulic. The common form in commercial cement clinker is the beta-C2S. The hydration products of beta-C2S are Ca(OH)2 and calcium silicate hydrate gel which is poorly crystallized substance known as tobermorite. The aim of the present work is to prepare B2O3-stabilized beta-C2S and investigate the hydration characteristics in the presence of granulated slag, fly ash and silica fume. The results indicated that the presence of these materials leads to the consumption of the liberated Ca(OH)2 and forming hydration products such as CSH and/or calcium aluminate hydrate. Also, these pozzolanic materials accelerate the hydration of beta-C2S.