PROCESS FOR IMPROVING ACTIVATION OF LATENTLY HYDRAULIC BASIC BLAST FURNACE SLAG IN THE PRODUCTION OF BUILDING MATERIAL

摘要

The invention relates to a method of improving the activation of latently hydraulic granulated basic blast-furnace slag in the manufacture of building materials. Known activating methods can be improved by a combination of activating agents, whereby the latently hydraulic slag is converted to a directly-acting hydraulic binder, which together with water and aggregate, such as sand and gravel, will produce a concrete of high tensile and high compression strength, and also a concrete which has good chemical resistance to attack by salt, sulphates and chlorides, and which is heat-resistant to temperatures up to 1000 DEG C. Activation is also able to eliminate the negative effect of aging. The improved activation is achieved by adding to the concrete mix a limited amount of alkali, a limited amount of Portland cement and optionally calcium oxide and amorphous silica powder, and an activator which includes magnesium oxide and phosphate.