RU2256630C1 - High-strength concrete - Google Patents

Abstract

FIELD: construction.

SUBSTANCE: high-strength concrete comprises, in mass %, 43.58-48.08 of Portland cement, 14.43-15.69 of sand, 25.7-27.84 of crashed stone, 0.25-0.27 of silicon-containing component, 044-0.47 of admixture, and 12.1-12.15 of water. The silicon-containing component is composed of sol H₂SiO₃ with a density of ρ = 1.014 g/cm³ and pH=5-6.

EFFECT: enhanced strength and waterproofness.

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Description

The invention relates to building materials and can be used for the manufacture of concrete products in both civil and industrial construction.

Known raw mix for the manufacture of high-strength concrete (II Akhverdov. High-strength concrete. M., Gosstroiizdat, 1961, p. 155), containing cement, aggregate, crushed stone, water and additive.

Concrete based on this raw material mixture has insufficient compressive strength and is characterized by increased water absorption.

Known raw mix for the manufacture of high-strength concrete (Moreno X. The use of high-strength concrete in the construction of high-rise buildings // Concrete and reinforced concrete. 1988 No. 11 p.29-31) containing cement, aggregate, water, chemical additive “Pozolit 100” and ash- ablation

The disadvantage of this technical solution is the lack of compressive strength and frost resistance.

The closest in technical essence to the claimed invention is high-strength concrete (Yu.M. Bazhenov. Concrete technology. Publishing house of the Association of construction universities (DIA), M., 2002, S. 377) containing Portland cement, silica-containing component, sand, gravel , silicate flour, additive and water in the following ratio of components, wt. %

Portland cement 3.5-4.5

Silica-containing component

represented by silica fume 3,5-4,5

Silicate flour 7.5-8.5

Sand 35.9-37.9

Crushed stone 41.9-43.9

Additive - superplasticizer 0.3-0.5

Water 3.5-4.3

The disadvantage of this technical solution is the lack of compressive strength, frost resistance and increased water absorption.

The problem to which the invention is directed, is the creation of high-strength concrete with increased compressive strength at design age, reduced water absorption and increased frost resistance.

The problem is achieved in that high-strength concrete contains Portland cement, sand, gravel, a silica-containing component, an additive and water. New compared with the high-strength concrete selected for the prototype, is that the silica-containing component is represented by H ₂ SiO ₃ sol with a density ρ = 1.014 g / cm ³ , pH 5 ... 6, and the additive is potassium ferruginous K ₄ Fe ( CN) ₆ , in the following ratio, wt.%

Portland cement 43.58-47.08

Sand 14.43-15.69

Crushed stone 25.7-27.84

Silica-containing component

represented by sol H ₂ SiO ₃

with a density ρ = 1.014 g / cm ³ pH 5 ... 6 0.25-0.27

Additive - potassium ferruginous K ₄ Fe (CN) ₆ 0.44-0.47

Water 12.1-12.15

The silica-containing component represented by H ₂ SiO ₃ sol with a density ρ = 1.014 g / cm ³ pH 5 ... 6 compacts the concrete structure. The additive - potassium ferruginous K ₄ Fe (CN) ₆ in combination with H ₂ SiO ₃ sol plasticizes the concrete mixture and increases the hydration activity of cement, with the formation of low-basic CSH (I) hydrosilicate of fibrous structure and a small amount of tobermorite C ₅ S ₆ H ₅ , joint the presence of which further compacts the structure of concrete.

At the filing date, according to the authors and the applicant, the claimed high-strength concrete is not known and this technical solution has world novelty.

The inventive combination of essential features exhibits a new property, which provides an increase in the density of the concrete structure. The combined presence of a silica-containing component represented by H ₂ SiO ₃ sol with a density of ρ = 1.014 g / cm ³ , pH 5 ... 6 and an additive - iron-sulfide potassium, K ₄ Fe (CN) ₆ , provides an extra sum effect, which manifests itself in an increase the hydration activity of cement, which results in an increase in compressive strength of concrete by 31%, an increase in the durability of concrete, estimated by the frost resistance parameter, which increases by 35%, and a decrease in water absorption by 20%.

Increasing the density of concrete, increasing the hydration activity of the starting minerals of Portland cement has a beneficial effect on the strength and durability of concrete.

A mixture including Portland cement, sand and gravel, a silica-containing component represented by H ₂ SiO ₃ sol with a density of ρ = 1.014 g / cm ³ , pH 5 ... 6, and potassium iron-synergy K ₄ Fe (CN) ₆ additive, provided high-strength concrete, characterized by increased compressive strength, reduced water absorption and increased frost resistance.

According to the applicant and the authors, the claimed invention meets the eligibility criteria - inventive step.

The claimed invention is industrially applicable and can be used in industrial and civil engineering.

The raw material mixture is prepared as follows: from distilled water and liquid glass Na ₂ SiO ₃ with a density ρ = 1.46 g / cm ³ , pH 11, a solution with a ratio of Na ₂ SiO ₃ : H ₂ 0 = 1: 20 is prepared. Dosage materials are placed in a glass container and stirred until a homogeneous solution with ρ = 1.014 g / cm ³ , pH 10 is obtained. A solution of Na ₂ SiO ₃ with ρ = 1.014 g / cm ³ , pH 10 is passed through a cation exchange column and sol N is obtained ₂ SiO ₃ with a density ρ = 1.014 g / cm ³ pH 5 ... 6, which is a silica-containing component. Dosage: the silica-containing component, the addition of potassium ferruginous is placed in the dosed water. The dosed components of the raw material mixture: Portland cement M400, sand - MKR = 2.1, crushed stone fr. 5 - 10 mm and water containing the dosed silica-containing component and the additive - iron-synergy potassium K ₄ Fe (CN) _6, are placed in a concrete mixer, where mixing the components and preparing the concrete mixture from which the required concrete products and samples are made for quality control according to GOST 10180.

Concrete hardening was carried out under normal conditions and the test results are presented in table 1.

Analysis of the data presented in table 1 shows that the proposed high-strength concrete according to this invention, in comparison with the prototype, increases compressive strength at the project age (28 days) by 31%, water absorption decreases by 20%, frost resistance increases by 35%.

Table 1 Sample Number The composition of high-strength concrete, wt. % Portland cement M400 aggregate silica component Additive Silicate flour water Compression strength at the age of 28 days, MPa Water absorption,% Frost resistance cycle Sand Mkr = 2.1 Crushed stone, fr. = 5-10 mm silica fume Sol H ₂ SiO ₃ with ρ = 1.014 g / cm ³ , pH = 5 ... 6 superplasticizer potassium ferruginous K ₄ Fe (CN) ₆ I prototype 4 36.9 49.2 4 - 0.4 - 8 3.8 54.0 4,5 300 2 43.58 15.69 27.84 - 0.27 - 0.47 - 12.15 67.8 3,7 400 3 45.33 15.06 26.77 - 0.26 - 0.455 - 12.3 70.7 3.6 400 4 47.08 14.43 25.7 - 0.25 - 0.44 - 12.1 68,2 3,7 400

Claims (1)

High-strength concrete, including Portland cement, sand, gravel, a silica-containing component, an additive and water, characterized in that it contains a H ₂ SiO ₃ sol with a density of ρ = 1.014 g / cm ³ , pH = 5-6 and as an additive as a silica-containing component - potassium ferruginous-synergistic K ₄ Fe (CN) ₆ , in the following ratio of components, wt.%: Portland cement 43.58-47.08 Sand 14.43-15.69 Crushed stone 25.7-27.84 Silica-containing component represented by sol H ₂ SiO ₃ with density ρ = 1.014 g / cm ³ , pH = 5-6 0.25-0.27 Additive - potassium ferruginous-synergistic K ₄ Fe (CN) ₆ 0.44-0.47 Water 12.1-12.15