With the purpose of accelerating the process of fine-grained concrete solidification on the basis of Ceyranchol volcanic ashes solution CaCl2 has been used. The method of mathematical planning of experiment helped optimize composition of alkaline-mineral fine-grained concrete with average density 1590-1670 kg/m3, ultimate strength at compression in dry condition of 136.8-362.3 kg/sm2 and softening ratio of 0.62-0.698.