RU2259970C1 - Method of concrete mix preparation - Google Patents

Abstract

FIELD: building materials, particularly used for producing concrete structures and articles.

SUBSTANCE: method involves metering quartz sand and binging material components; mixing above materials and forming articles. Binding material is ash-and-alkaline binder including fly-ash taken from the first zone and obtained from combustion of brown coal at heat generating plant and carbon-containing liquid glass. Liquid glass is produced from large-tonnage crystalline silicon production waste obtained at aluminum smelter, namely of microsilica, and including highly-dispersed carbon mixtures, namely graphite and carborundum with silica modulus n=1 and 1.40-1.53 g/cm³ density, in amount of up to 6-7% by weight. Concrete mix components are taken in the following amounts (% by weight): liquid glass obtainer from microsilica - 15.2-31.4, fly-ash - 23.8-48.5, quartz sand - 29.2-52.3. The mix may be hardened under temperature of up to -18°C.

EFFECT: extended range of concrete mix hardening temperatures.

1 ex, 2 tbl

Description

The invention relates to the construction materials industry and can be used in the manufacture of structures and concrete products.

Known hydraulically hardening composition, hardening at low temperatures and containing 50-80 parts of BCM, 13-35 parts of fly ash, 0-10 parts of metakaolin, 0-6 parts of slag, 0-4 hours of an additive that regulates setting time astringent and 1-5 hours of potassium carbonate [US patent No. 4842649, 1989].

The disadvantage of this composition is its multicomponent.

The closest analogue to the described invention is a method for preparing a concrete mixture, including dosing of quartz sand, components of a gold-alkali binder containing carbon-containing liquid glass, made from large-tonnage waste from the production of crystalline silicon of the Bratsk aluminum plant - silica fume and containing up to 6-7 wt.% Highly dispersed carbon impurities - graphite C and carborundum SiC, with a silicate module n = 1 and a density ρ = 1.45-1.49 g / cm ³ and fly ash from the burning of brown Kansko-Achinsky coal at TPP-7 in Bratsk, Irkutsk region, mixing of components and molding of products [RF patent No. 2130904, 1999].

The disadvantage of the described method of preparing a concrete mixture is the ability to harden only when steaming, which significantly limits the scope of such a concrete mixture.

The problem solved by the invention is to improve the quality of concrete.

The technical result is the expansion of the hardening temperature range to -18 ° C.

The specified technical result in the implementation of the invention is achieved by the fact that the preparation of concrete mixture includes dosing quartz sand and binder components, mixing and molding products, and as a binder, a gold-alkali binder (ZSCH) is used, consisting of fly ash of the first field obtained from burning brown Kansko-Achinsky coal at TPP-7 in Bratsk, Irkutsk region and carbon-containing liquid glass made from large-tonnage waste from the production of crystalline silicon from Bratsk aluminum Avoda - silica fume and containing up to 6-7 wt.% highly dispersed carbon impurities of graphite C and carborundum SiC, with a silicate module n = 1 and a density of ρ = 1.40-1.53 g / cm ³ in the following ratio of components, wt.% :

Carbon Liquid Glass silica fume 15.2-31.4 Fly ash I field 23.8-48.5 Quartz sand 29.2-52.3

The chemical composition of fly ash is presented in table 1

Table 1
The average chemical composition of fly ash of the first field of the TPP is 7 (Bratsk) The content of compounds,% by weight p.p.p. SiO ₂ Fe ₂ O ₃ + FeO Al ₂ About ₃ CaO MgO SO ₃ R ₂ O 51.9 7.9 10.8 20.1 5.1 2.2 0.6 3.2

Example. Concrete mixture was prepared as follows. The fly ash of field I in the amount of 23.8% was mixed with 52.3% of quartz sand and 23.9% of carbon-containing liquid silica glass with silica module n = 1 and density ρ = 1.40 g / cm ^{3 were} shut. The mixture was mixed in a forced-action concrete mixer for 2-3 minutes. The samples were formed on a laboratory vibratory platform. Samples in the molds solidified at a temperature of T = 16-20 ° C in air-dry conditions for 24 hours, after which they were redressed and placed in a freezer at a temperature of -18 ° C for further testing. The test results are shown in table.2.

table 2
Properties of concrete based on ash-base binder, hardening at low temperature Hardening temperature Compressive strength, MPa aged Frost resistance. cycles -18 ° C 1 day 3 days 7 days 14 days 28 days more than 200 5.7 10,2 11.6 15.9 25,2

An analysis of the data shows that the proposed concrete mixture is able to gain strength not only when steaming at T = + 80 ... 90 ° C (as in the prototype), but also at low temperatures (-18 ° C), which significantly expands the possibilities of application such concrete mix.

Claims (1)

A method of preparing a concrete mixture, including dosing quartz sand and binder components, mixing and molding products, characterized in that a binder is used as a binder, consisting of fly ash from field I obtained from burning brown Kansk-Achinsk coal at TPP-7 Bratka, Irkutsk Region, and carbon-containing liquid glass made from large-tonnage waste from the production of crystalline silicon from the Bratsk Aluminum Plant - silica fume and containing up to 6-7 wt.% highly dispersed carbon impurities of graphite C and carborundum SiC, with silicate module n = 1 and density p = 1.40-1.53 g / cm ³ in the following ratio of components, wt.%: Carbon Liquid Glass silica fume 15.2-31.4 Fly ash I field 23.8-48.5 Quartz sand 29.2-52.3