SU768778A1 - Concrete mix - Google Patents

Description

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The invention relates to compositions of concrete mixtures and can be used in the construction of structures for protection from radioactive effects of nuclear reactors, nuclear power plants, enterprises for the development and processing of isotopes and other special structures. . A concrete mix is known, including cement, sand, crushed stone, ore and water 1. A concrete mix is also known, including cement -7–9%, finely ground additive from ferrobor slag - 5–8%, sand from ferrobor slag 18–25%, crushed stone ferroboric slag 48-64% and water 2.

The known concrete mixture is closest to the invention in its technical essence and the achieved result.

The disadvantage of these concrete mixes is the relatively low bulk density, one of the main indicators of the effectiveness of protection against radioactive radiation.

The aim of the invention is to increase the density of concrete.

The goal is achieved by the fact that a concrete mix, including cement, finely ground additive from ferrocore mill slag, sand, crushed stone and water, contains sand and rolled gravel in the following ratio of components, mass %:

Cement 6,70-14,40

Grinder additive

from ferrobor slag 5,00-10,65 Sand from scale

5 rolling27,60-33,20

Crushed cinder

rolling34,65-48,40

Water 6.80-12.30

The essence of the invention is that 10 in the composition of the concrete mixture is introduced as a crushed stone and sand mill scale - waste rolling production. Scale of rolling is dense (, 0-5.1 g / cm), heavy material (bulk weight 15 Y 2350-2835 kg / m) and contains iron (Revost 70.0-75.0%). In terms of their physical and mechanical properties, mill scale rolls out beyond traditional aggregates — magnetite and hematite ores — for which the density varies from 3.2 to 4.3 g / cm and the bulk density is 2300-270 kg / m3.

According to the content of iron oxides, scale rolling also corresponds to high-quality ore materials. The composition of the concrete mixture includes finely ground ferroboric slags, which effectively absorb secondary v-out 0 radiation (up to 7.7 MeV) arising in iron upon the absorption of neutrons and thermal neutrons.

The concrete mixture according to the invention possesses a complex of universal protective properties, both of St y-radiation, and from secondary 7-radiation and thermal neutrons. Higher, but compared with traditional materials, the radiation-resistant properties of the concrete mixture are determined by the optimal qualitative and quantitative combination of its components.

The concrete mix is made up of local, cheap, non-deficient materials - rolling and ferro-syllav production waste, which are usually found at one metallurgical plant, such as, for example, at the Novolinetsky metallurgical plant. In addition, the main component of the proposed concrete mix, mill scale, does not require additional costs for its grinding, as it has an acceptable particle size distribution (it is advisable to screen only fractions of more than 20 mm).

The use of mill scale as a filler for radio-resistant concrete significantly expands the base of cheap building materials for energy construction.

When using mill scale in combination with slabs of ferrobor, the concrete mix is prepared according to the following technology. First, the cement is mixed with the finely ground additive from the ferroboric slags until homogeneous and the mixture is closed with water. Thereafter, sand and mill scale are added to the dough successively, which are mixed with the dough until a homogeneous mass is obtained. The prepared mixture is placed in a mold with a size of 15X15x15 cm and compacted on a standard vibrating plate for 30-45 seconds. Hardening of the cubes is carried out for 28 days in a normal storage chamber. After that, the cubes are subjected to testing but determining the properties of the concrete mix but GOST 10180-74.

Example 1. 6.67 (by weight) slag Portland cement mixed with 4.95% fine ......

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to obtain a uniform composition of the ferroboric slag, and the mixture is closed with a water of 6.80%. Thereafter, 33.18% of sand, 14.5% of crushed stone fraction 5-10 and 33.9% of crushed stone fraction 10-20 from mill scale are added in succession to the mixture. The mixture is again stirred until a homogeneous composition is obtained. Mixed concrete mix is placed in the form -cube size 15X15X X15 cm in two steps with compaction on a standard vibronisite for 45 seconds. The hardening of the cubes occurs in the normal hardening chamber for 28 days. After that, the samples are subjected to tests to determine the bulk density and cubic strength of concrete.

Example 2. 10.9% (by weight) of slag cement and cement are mixed with 6.57% of finely dispersed ferroboron slag until a uniform composition is obtained, and the mixture is sealed with water of 8.05%. After that, 29.42% of sand, 13.8% of crushed stone fraction 5-10, 31.26% of crushed stone are added to the mixture successively.

fractions 10-20 of rolling mill scale and again mix the entire mixture. Thoroughly mixed concrete mix is placed in molds measuring 15x15x15 cm. Further compaction of the concrete mix, storage and

Testing of concrete samples is carried out as in Example 1.

Example 3. 14.40% (by weight) of slagaceous cement was mixed with 10.65% of finely divided ferroboron slag to obtain a uniform composition and the mixture was sealed with water of 12.3%. After that, 27.6% of sand, 10.8% of crushed stone fraction 5-10, 24.25% of crushed stone fraction 10-20 from mill scale and again

mix the whole mixture. Thoroughly mixed concrete mix is placed in forms 15X15x15 cm in size. Further compaction of the concrete mix, storage and testing of concrete samples is carried out

as in example 1.

Physico-mechanical properties of concrete in examples 1, 2 and 3 are given in the table.

Thus, concretes of the above compositions by the size of the bulk mass, strength and chemical composition can be used in the construction of facilities serving for biological protection from radioactive radiation. The concrete of the invention has a higher bulk density and, as a consequence, a higher density, therefore, it has improved zash properties, from radioactive radiation. .

The use of concrete in the protection of radioactive waste from metallurgical production makes it possible to reduce the cost of concrete mixtures, eliminate the use of imported, expensive, and their scarce materials: limoiite, magnetite, barite, etc.

In addition, the economic efficiency from the application of the proposed concrete mix is achieved by the fact that the thickness of the protective barrier can be reduced due to the increased complex properties of concrete based on mill scale and ferrocore slag.

Precast monolithic products and structures made of concrete mixture according to the invention can be used in the construction of nuclear power plants, isotopes producing and processing plants, transport power plants, etc.

Claims (2)

Invention Formula Concrete mix, including cement, finely ground additive from ferrobor slag, sand, crushed stone and water, characterized in that, in order to increase the density, it contains sand and crushed stone from mill scale in the following ratio of components, mass. %: Cement 6,70-14,40 Grinder additive from ferrobor slag 5,00-10,65 Sand from scale rolling27,60-33,20 Crushed cinder rolling34,65-48,40 Water 6.80-12.30 Sources of information taken into account during the examination 1. Komarovsky A. N. Construction of nuclear installations. M., Atomizdat, 1965, p. 29, tab. 5.6. 2. Copyright certificate No. ... on application no. 2515929/33, cl. C 04B 15/00, 1977 (prototype).