Repair mixture for concrete   ICBM 300   Appointment : Dry construction mix MBR 300 is intended for the preparation of building fine-grained concrete used for repairing concrete structures, monoling joints, technological holes, sealing cracks, etc.   Composition :             Dry construction mix MBR 300   is a polymer-mineral fine-grained mixture obtained by intensive mixing of fractionated sand, Portland cement and a complex of modifying additives.   Concrete preparation : For the preparation of dry building mix MBR 300   poured into clean fresh water, constantly mixing until a homogeneous mass with a wooden spatula, electric drill with mixer nozzle or low-speed forced-action stirrer. Mixing is carried out for at least 5 minutes. The amount of water required for the preparation of concrete is determined from the ratio of 0.2-0.22 L per 1 kg of dry construction mixture (5.5-5.75 L of water per bag of 25 kg of dry construction mixture). The exact amount of water is determined when the consistency required for the work, the plasticity of the building concrete, is achieved. Ready concrete to stand   for 5 minutes to obtain complete homogeneity and then re-mix. Ready concrete must be used within 1 hour.   Preparation of the working surface (base) : The working surface (base) must be strong, durable, free from dust, dirt, oils, fats, wax, bitumen, paint residues. Cracks are broken, old fragile concrete is removed, the released reinforcement is cleaned of rust. The prepared surface is cleaned of dust using compressed air. Weak old concrete or mortar reinforced with polymer-mineral primer Apply a highly absorbent surface to the primer. Metal parts must be treated with an anti-corrosion solution.   Concrete Application : Before applying concrete, the prepared surface is abundantly moistened. Allow the water to soak in and then apply the concrete manually. For large areas of the surface to be repaired, repair of places subject to large bending loads, the layer of applied concrete, the thickness of the concrete layer of more than 50 mm must be reinforced with an alkali-resistant fiberglass mesh, metal reinforcement or fiber. Concrete laying is carried out without interruption until complete completion, or by grips. Before applying subsequent layers, it is necessary to moisten the previous layer, i.e. observe the processing method - “wet on wet”. The temperature of the working surface when applying MBR300 should be not less than + 5ºС and not more than 30ºС. The temperature of the working surface when applying MBR300M should be at least -10ºС and not more than + 5ºС. Concrete consumption depends on the type of repair. To repair a damaged horizontal surface of 95-110 kg per 1 sq. M of the surface to be repaired with a layer thickness of 50 mm.   Specifications : Colour Gray Astringent Portland cement Aggregate fractionated sand Placeholder fraction up to 1.0 mm Water retention capacity not less than 98% Maximum thickness in one run 50 mm Water consumption for cooking 0.2-0.22 L per 1 kg of mixture Viability at least 1 hour Hardening time 24 hours Work surface temperature For MBR-300 For MBR-300M   from + 5˚С to + 30˚С from -10˚С to + 5˚С Compressive strength (grade) 300 kgf / m 2 (30 MPa) Peel strength from concrete surface 18 kgf / m 2 (1.8 MPa) Frost resistance no less than 400 cycles   Safety precautions : Portland cement contained in the mixture, when interacting with water, forms an alkali. Avoid getting ready-made mortar on the skin and mucous membranes. In case of contact, rinse the contact area with clean running water.   Shelf life : Store mortar in a dry place at a relative humidity of 60%, temperature from –50 to +50 ˚С. Shelf life in the manufacturer’s packaging 6 months from the date of manufacture