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Introduction The hydration of the cement minerals C 3 S (3CaO·SiO 2 ), C 2 S (2CaO·SiO 2 ), C 3 A (3CaO·Al 2 O 3 ) and C 4 AF (4CaO·Al 2 O 3 ·Fe 2 O 3 ) is an exothermal chemical process. At early ages, the generated heat can
) are fulvic acids (FA) and humic acids (HA); FA are fractions of NOM soluble at all pH values, while HA are soluble only in alkaline solutions [ 2 ]. Hydration is the crucial factor playing role in biological function of molecules in both living
]. Calorimetric studies of Portland cement [ 1 , 2 ] and calcium aluminate cement [ 3 , 4 ] pastes show that the FCC catalyst remarkably influences the hydration of various cements. It has been found that, in the compositions with Portland cement, the FCC
, the cement has no longer enough water to hydrate and the final properties of the mortar are altered [ 3 ]. Thus, cellulose ethers are additives commonly used in mortars as water retention agents, as thickeners and film formers [ 4 ] to prevent water
assessment of mineralogical composition and texture of modified clinkers [ 1 , 4 ]. Data on combined effect of different type of compounds or regarding the influence of foreign ions on the cement hydration and hardening processes are less numerous [ 4 – 8
of the main phases of normal Portland cement clinker, plays an important role in the early stage of hydration process, and it is believed to be the responsible species for the setting and hardening behaviours of cement. The ionic substitution of this
England in years 1973–1974) CACs are applied to structural concrete much less often than Portland cements [ 1 – 3 ]. The deterioration of strength is related with a process of conversion of aluminate hydrates. In case of CACs the nature of hydration
temperatures [ 4 ]. Preparation of such quality product based on aluminate cement requires extensive studies. It is difficult to predict the hydration process of new cement-based materials, because not only the influence of addition on hydration of this cement
of PC with CAC has been found to result in a great decrease of compressive strength especially at later age [ 2 , 6 , 7 ], which becomes a barrier for the application of PC/CAC mixtures. It may result from the film-like hydration products that
Abstract
In this work, the hydration rate and products of blended zeolite cements were studied for periods up to 360 days. Thermoanalytical methods (TG/DTG and DTA) were applied in order to evaluate the hydration rate of blended cements, while. X-ray diffraction and FTIR spectroscopy were used in order to identify the hydrated products. As it is concluded the incorporation of zeolite in cement contributes to the consumption of Ca(OH)2 formed during the cement hydration and the formation of cement-like hydrated products. The pozzolanic reaction of the zeolite is rather slow during the first days of hydration but it is accelerated after the 28 days.
