Influence of Cements Containing Calcareous Fly Ash on Rheologlcal Properties of Fresh Mortars and Its Variability

摘要

In the research influence of cements containing calcareous fly ashes W as non-clinker constituent produced by different methods on rheological properties of mortars and its variability is presented. In comparison to mortars with CEM I mortars with cements CEM II/A-W, CEM II/B-W, CEM IV/B-W are characterized by worse workability and faster workability loss, the greater the more fly ash W is in cement. However, using cements CEM II/A-W, CEM II/B-W produced by intergrinding of the constituents or homogenization with ground fly ash W it is possible to obtain mixtures with acceptable rheological properties. Obtained results shows significant influence of properties of the fly ash W on the variability of rheological properties of cement CEM II/B-W mortars. However, if fly ashes W with a bulk density of less than 900 kg/m~3 are not used for the production of cement, it is possible to achieve variability of the rheological properties of mortars, to a level not deviating significantiy from other types of cements.