Mixed gypsumless portland cement and its production.

摘要

The invention relates to mixed gypsumless Portland cement the application of which enables to achieve high initial and long-lasting strength. The cement contains 60 to 96.7 mass-% of gypsumless Portland cement clinker with a specific surface of 350 to 550 m<2>/kg, 3 to 40 mass-% of ground latently hydraulic matter, such as granulated blast-furnace slag, light ash etc., these two components having been ground in the presence of 0.01 to 0.1 mass-% of a liquid milling admixture, advantageously with a synthetical surface-active matter with wetting properties, and containing further 0 to 20 mass-% of fine amorphous SiO2 and/or 0.1 to 3 mass-% of a sulfonated polyelectrolyte or ligninsulfonate, and from 0.5 to 6 mass-% of an alkali carbonate, hydrogen carbonate or hydroxide.