FIELD: construction.
SUBSTANCE: invention relates to production of construction materials, articles and structures and can be used in production of small-size construction articles from dense, high-strength, fine-grained concrete. Method of concrete pressing with vibration from rigid, plasticized concrete mixture includes reduction of concrete mixture in matrix with piston, moistening of concrete after pressing and holding in normal temperature-humid conditions to its design strength setting. In addition, electric heating of concrete mixture at temperature of up to 100 °C for 5–7 minutes. Concrete mixture containing cement GC-500, water, aggregates in the form of quartz sand of uniform grain composition of fraction 0.16–2.5 mm and crushed sand of igneous rocks with grain density of 2.76 g/cm3, 2.5–5 mm fractions, with water-to-cement ratio of up to 0.22, with plasticizing hydrophobic, sealing hydrophilic and ultrafine additives. At that, after short-term preliminary vibration there performed is pressing, up to 100 MPa, and prolonged pressing till 20–30 min, in process of which up to 25 % of tempering water is squeezed. Concrete hardens and accelerates gaining fastening strength under pressure and electric heating performed after beginning of action of preset pressing pressures. After pressing, concrete is held for 28 days in normal temperature and humidity conditions with periodic after-drying and moistening thereof for 3 days.
EFFECT: high strength and density of concrete, shorter time for obtaining design strength of concrete, as well as higher quality of concrete articles.
1 cl, 2 dwg, 2 tbl
