RU2758307C1 - Charge for manufacture of cellular heat-resistant concrete - Google Patents

Abstract

FIELD: construction materials industry.

SUBSTANCE: invention relates to the field of construction materials, in particular to heat-resistant concrete intended for use in conditions of elevated temperatures. The charge for the manufacture of cellular heat-resistant concrete contains, by wt. %: Portland cement 50.40-54.30, chamotte powder with a particle size of no more than 0.63 mm 0.63 - 0.75, sand with a grain size of no more than 0.63 mm 6.10 - 7.78, a protein-based foaming agent 0.35-0.39, basalt fiber with a fiber length of 6-12 mm 1.50 - 1.70, water 37.12 - 38.98.

EFFECT: increase in the tensile strength during bending while maintaining the thermal conductivity coefficient of cellular heat-resistant concrete.

1 cl, 1 tbl, 1 ex

Description

The present invention relates to the field of building materials, in particular to refractory concretes intended for use at elevated temperatures.

Known charge for the manufacture of light heat-resistant concrete, including an aluminosilicate lightweight aggregate and cement, contains expanded clay as an aluminosilicate light aggregate with a fraction of 1-6 mm and a fraction of 0-1 mm, and as a cement - Portland cement with the following ratio of components, wt%: expanded clay fractions 1-6 mm - 30-55, expanded clay of fraction 0-1 mm - 5-25, Portland cement - 35-45. (RU 2291135, IPC С04В 38/08 (2006.01), 10.01.2007).

The disadvantages of this charge are low tensile strength in bending and high thermal conductivity.

The closest technical solution is a charge for the manufacture of aerated heat-resistant concrete intended for thermal insulation of heat-generating devices and thermal furnaces, containing a binder - high-alumina cement 15-30%, clay 40-60%, as a filler - scrap and scrap of spent chamotte, dinas and periclase-chromite refractories , 15-30% synthetic foaming agent based on anionic surfactants, air-entraining additives in concrete and protein foaming agents: Penostrom, Morpen, P0-6K, SDO and Neopor, stabilizer based on PVA and urea-formaldehyde liquid in the amount of 1.2-1.7% of the mass of the binder, water (Bolotnikova Olga Vasilievna "Heat-resistant cellular heat-insulating concretes on a mineral binder": abstract of dis. candidate of technical sciences: 05.23.05 / Penz. state. t of architecture and construction. - Penza, 2006. - 23 p.).

The disadvantage of the known technical solution is the low tensile strength in bending and a high coefficient of thermal conductivity, as well as the high cost of raw materials.

The present invention is directed to the manufacture of a new charge for the manufacture of aerated refractory concrete with high tensile flexural strength and low thermal conductivity. The technical result is an increase in tensile strength in bending and a decrease in the coefficient of thermal conductivity.

The technical result is achieved by the fact that the charge for the manufacture of aerated refractory concrete based on Portland cement binder, containing sand with a grain size of no more than 0.63 mm, fireclay powder with a particle size of no more than 0.63 mm, water, a foaming agent on a protein basis "Foamcem", additionally contains basalt fiber at the following ratios, wt%:

Portland cement 50.40-54.30 Sand 6.10-7.78 Chamotte powder 0.63-0.75 Protein Foamer 0.35-0.39 Basalt fiber 1.50-1.70 Water 37.12-38.98

The introduction of basalt fiber leads to a significant increase in tensile strength in bending, due to the reinforcement of the cement stone, as well as to a decrease in its thermal conductivity coefficient, due to a reduced thermal conductivity coefficient of basalt fiber.

EXAMPLE OF A SPECIFIC PERFORMANCE

Production of a charge for the manufacture of aerated heat-resistant concrete on a cement binder.

1. Dosing and loading of dry components into the mixer takes place in the following sequence:

- Portland cement with slag CEM II / V-Sh 42.5N, meeting the requirements of GOST 31108-2016;

- fine sand in accordance with GOST 8736-2014 “Sand for construction work. Specifications "with grain size no more than 0.63 mm;

- fireclay powder fraction, with a particle size of no more than 0.63 mm;

- water in accordance with GOST 23732-79, while basalt fiber is introduced into the mixing water according to TU 5952-002-13307094-2008, grade BS17-12.7 (1/2 ") r-KV-13 with fiber length 6- 12 mm in the specified quantity.

2. Mixing of raw materials in a mixer.

3. Porization of the mixture due to separately prepared foam from the foaming agent solution. The following brands can be used as a foaming agent: Addiment SB 31L (trade mark RENIMENT SB 31L, manufacturer SIKA ADDIMENT GmbH В-69171 Leimen, Germany, base - protein hydralizates, dark brown liquid, foaming pH range: 6 -10 (Khitrov A.V., abstract for the competition for the academic st. D.Sc. "Technology and properties of foam concrete taking into account the nature of the introduced foam." St. Petersburg, PGUPS, 2006)), "FoamCem" (the main active substance - protein hydrolyzate; field of application: foaming agent for the preparation of lightweight aerated concrete; manufactured by Laston Italiana SPA), Neopor (manufactured by Neopor System GmbH, Germany, protein base, dark liquid, surface tension 45-55 J / m ² , pH range foaming: 6-8 (Khitrov A.V., abstract for competition for the academic article, candidate of technical sciences "Obtaining modern autoclaved foam concrete, taking into account the nature of the introduced building foams." St. Petersburg, PGUPS, 2000).

4. Laying the prepared aerated concrete mixture into molds;

5. Curing of aerated concrete within 28 days of normal hardening;

6. Drying of finished products within 48 hours at a temperature of 100 ± 2 ° C in accordance with GOST 20910-19;

Further, the physical and mechanical characteristics of aerated concrete are determined - tensile strength in bending and the coefficient of thermal conductivity. The obtained physical and mechanical characteristics of aerated heat-resistant concrete are presented in the table.

Analysis of the results obtained shows that heat-resistant cellular concrete based on the proposed composition has an increased tensile strength in bending and a reduced coefficient of thermal conductivity.

table

No. Average density, kg / m ³ Composition Physical and technical characteristics Flexural tensile strength, MPa Thermal conductivity coefficient, λ
W / (m ° C) Prototype 500 High-alumina cement 7.87
Clay 31.74
Breakage and scrap of spent fireclay refractories 15,87
Foaming agent 0.08
Stabilizer 0.07
Water 44.37 0.081 0.12 1 500 Portland cement with slag CEM II / V-Sh 42.5N 54.30
Fine sand in accordance with GOST 8736-2014 with a grain size of no more than 0.63 mm 6.10
Fireclay powder with a particle size of no more than 0.63 mm 0.63
Protein-based foaming agent "FoamCem" 0.35
Basalt fiber 1.50
Water 37.12 0.11 0.11 2 500 Portland cement with slag CEM II / V-Sh 42.5N 52.35
Fine sand in accordance with GOST 8736-2014 with a grain size of no more than 0.63 mm 6.94
Fireclay powder with a particle size of no more than 0.63 mm 0.69
Protein-based foaming agent "FoamCem" 0.37
Basalt fiber 1.60
Water 38.05 0.12 0.10 3 500 Portland cement with slag CEM II / V-Sh 42.5N 50.40
Fine sand in accordance with GOST 8736-2014 with a grain size of no more than 0.63 mm 7.78
Fireclay powder with a particle size of no more than 0.63 mm 0.75
Protein-based foaming agent "FoamCem" 0.39
Basalt fiber 1.70
Water 38.98 0.10 0.12

Claims (2)

A charge for the manufacture of aerated heat-resistant concrete, containing cement, chamotte powder, protein-based foaming agent and water, characterized in that Portland cement is used as cement, chamotte powder is used with a particle size of no more than 0.63 mm, and additionally it contains sand with a size grains no more than 0.63 mm and basalt fiber with a fiber length of 6 - 12 mm, with the following ratio of components, wt%: Portland cement 50.40 - 54.30 Sand 6.10 - 7.78 Chamotte powder 0.63 - 0.75 Protein Foamer 0.35 - 0.39 Basalt fiber 1.50 - 1.70 Water 37.12 - 38.98