High-strength active powder concrete and preparation method

Abstract

The invention discloses a cement-based composite material - high-strength active powder concrete which comprises the following raw materials by weight: 40-55 parts of quartz sand, 25-30 parts of cement, 0-10 parts of fly ash, 0-7 parts of silica fume, 1-4 parts of steel fibers, 1-2 parts of water reducers, and 2-7 parts of water; in the components, the particle size of quartz sand is less than 1.25 mm, wherein the weight content of SiO2 is 97%. The mixing preparation comprises the following steps: weighing quartz sand and steel fibers according to the mixing ratios, adding into a stirring pot, performing dry mixing for 2 min; weighing cement and a special composite admixture according to the mixing ratios, adding into the stirring pot, performing dry mixing with quartz sand and steel fibers for 2 min; finally adding the high-efficient water reducer and water together, stirring for 6 min; after the stirring of the concrete, blanking and molding. The concrete of the invention has ultrahigh strength, low brittleness, high durability, and high compactness, brings into better play of the excellent performance of the active powder concrete, and reaches the purposes of less maintenance or free of maintenance, and prolongation of structure service life.

Description

technical field [0001] The invention belongs to the technical field of concrete materials, and in particular relates to a material used for concrete prefabricated components in the current civil engineering field. Background technique [0002] Reactive powder concrete (RPC) is a cement-based composite material with ultra-high strength, low brittleness, high durability and high density. RPC material has extremely low permeability, high resistance to environmental medium erosion and good wear resistance, and the structure and performance of the interface transition zone have been well improved, and it has strong resistance to freeze-thaw cycles, salt corrosion and carbonization. resistance. [0003] Reactive powder concrete (RPC), as a new type of concrete material, not only can obtain an ultra-high compressive strength of 200MPa, but also has a flexural strength of 30MPa, which effectively overcomes the high brittleness of high-performance concrete. [0004] Compared with...

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Problems solved by technology

[0005] However, there are still some deficiencies in the existing reactive powder concrete technology. First, there are defects in the selection of components in the formula and the proportion configuration, which does not really reflect the reactive powder concrete. (RPC) superiority; 2. The aggregate particle size in the formula is large, resulting in poor uniformity of the internal structure; 3. The ratio of SiO2 and soil content in the sand is not controlled. lead to unstable quality

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