HARDENING ACCELERATOR CONTAINING ETTRINGITE AND CALCIUM SILICATE HYDRATE

摘要

The invention concerns a process for the preparation of a calcium silicate hydrate and ettringite containing hardening accelerator composition by reaction of a water-soluble calcium compound, silicate compound, aluminum compound and a sulfate compound, wherein the molar ratio of silicon to sulfate is from 2/1 to 30/1 and the reaction of the four compounds being carried out in the presence of an aqueous solution which contains a comb polymer suitable as a plasticizer for hydraulic binders. Also concerned are the use of said accelerators in building material mixtures, the building material mixtures containing said accelerators and a process for the preparation of a sprayable binder composition in which said accelerators are used.