FIELD: chemistry.
SUBSTANCE: invention relates to techniques for producing unfired fly ash aggregate based on acidic ash and additives. The composition for producing unfired fly ash aggregate, which includes acid ash from heat power industry, portland cement, ground blast-furnace slag, an additive which accelerates hardening of gummy granules - sodium sulphate, additionally contains ground basic rock - hornblendite, with the following ratio of components in wt %: portland cement - 15-20, ground blast-furnace slag - 0-25, sodium sulphate - 2; hornblendite - 10-25, acidic ash - the balance.
EFFECT: high strength and frost resistance of unfired fly ash aggregate through optimisation of the composition which is taken for granulation.