DRY CEMENT-SAND MIXTURE PROGRESS-II Russian patent published in 2000 - IPC

FIELD: preparation of water impermeable solutions and concretes, manufacture of concrete and reinforced concrete products and structures and also repair and reconstruction of rooms with higher moisture content. SUBSTANCE: dry cement-sand mixture comprises, wt %: portland cement, 21-42; sand, 50-75, expanding mineral additive, 4-8. Said additive comprises, wt %; volcanic rock at silicon oxide to aluminium ratio of more than 8.5; 1-15 wt % pumice, 40- 85; gypsum, 10-35; dolomite, 0-30; microsilica, 0.5; plasticizer, 1-3. Mixture comprises hardening and setting accelerator, and/or hardening and setting retarder, and/or water repellant. EFFECT: improved properties of the mixture. 2 cl, 2 tbl