Properties of Portland-composite cements with zeolite tuff

Growing requirements for protection of the environment every year gradually increase production of cements with a high content of mineral additives and clinker cements should be considered as cements for special purposes. The strong development of a quaternary Portland cement composite system containing blast-furnace slag, zeolite tuff and limestone powder is presented. The composition and particle size distribution of the constituents are optimized by the incremental coefficient of the surface activity of the zeolite-containing Portland composite cements. Zeolite tuff and limestone powder of high specific surface area lead to the increase of the surface activity of the entire system and a corresponding improvement in the performance of the cement. It was shown that low-energy Portland-composite cements “green cements” obtained by separate grinding are characterized by higher early compressive strength. The optimization of Portland-composite cements was carried out and the relationship between the phase composition, microstructure and strength of the cement matrix were investigated. The main role of zeolite is to improve the properties of cement stone by reducing the quantity and size of hydrate calcium hydroxide with increasing of low alkali calcium hydrosilicates. It is shown that a synergistic combination of mineral additives of different groups with substantial reduction of high energy-consumption clinker component in the Portland-composite cements allows to improve rheological properties and provides of strength increase of binder.