PROTECTIVE COMPOSITION FOR CONCRETE SURFACES AND METHOD FOR PROTECTING CONCRETE SURFACES Russian patent published in 1997 - IPC

FIELD: manufacture of building materials. SUBSTANCE: composition contains cement, sand, inorganic ionogenic additive and has the following component contents (in wt %): sodium nitrate, 0.9-1.8; sodium carbonate, 2.0-3.0; sodium sulfate, 2.5-3.6; calcium chloride, 0.05-0.15; calcium carbide, 0.75-1.15; calcium hydroxide, 0.8-1.0; cement, 36.0-40.0; sand, 39.0-49.0; and water, the balance. To protect concrete surface, the latter is subjected to piercing uniformly distributed cavities to the depth of the open concrete pore system and subsequently applying protective composition, wherein the area of obtained cellular surface equals 1.15-1.36 area of protected surface. Protective layer exhibits following characteristics: mud fill degree 95-100%, compression strength 50 MPa, tensile strength 7 MPa, strength of adhesion to old concrete is manifested as break down within the old concrete, waterproofness after applying protective layer 16 atm, that after removing protective layer 14 atm, cold resistance 300-350 cycles, hardening time 25-40 min. Invention may find use for buildings under repair and new buildings and structures. EFFECT: improved performance characteristics of concrete. 2 cl, 3 tbl