WATER IMPERMEABLE CONCRETE Russian patent published in 2000 - IPC

FIELD: building materials industry, more particularly industrial manufacture of products and structures and repair and reconstruction of rooms with higher moisture content. SUBSTANCE: water impermeable concrete comprises portland cement, sand and expanding mineral additive comprising volcanic rock, gypsum, dolomite, microsilica, and plasticizer. Expanding mineral additive includes volcanic rock at silicon oxide to aluminium oxide ratio of more than 3.5 and comprises 1-15 wt % of pumice, ratios of additive components being as follows; wt %: said volcanic rock, 40-85; gypsum 10-35; dolomite 0-30; microsilica, 0-5; plasticizer, 1-3; concrete comprises sand with fraction size of greater 0.14 mm and crushed stone, ratios of component, 400-500; additive, 70-100; sand with fraction size of greater than 0.14 mm, 500-700; crushed stone, 600-800, and water till water cement ratio is reached, 0.3-0.4. Water impermeable concrete comprises hardening accelerator and/or hardening retarder and/or water repellant. EFFECT: greater strength and higher frost resistance of both shrinkage-free and expanding water impermeable concrete. 2 cl, 2 tbl