RU2332389C1 - Production method of concrete products - Google Patents

Abstract

FIELD: chemistry.

SUBSTANCE: method relates to concrete products preparation (slabs, blocks) at freezing temperature. The method of concrete products preparation includes dosing of cement, filler material, water, antifreeze additive, preparation of concrete mixture and placing of concrete and maturing at freezing temperature. The particles, colored with the pigments of cement paste without an antifreeze additive and cooled down to freezing temperature are added into the concrete mixture which is cooled down to freezing temperature. After maturing of the concrete mixture, concrete products are aged at positive temperature till the particles are hardened. The particles take 0.1-10% of concrete mixture's volume.

EFFECT: enhancement of freeze-thaw resistance.

1 ex

Description

The invention relates to the production of concrete products (plates, blocks) at negative ambient temperatures.

A known method of manufacturing concrete products, including dosing of cement, aggregates, water, pigments, antifreeze additives, preparation of concrete mix, laying the mixture, hardening at low temperatures, machining [1]. For coloring concrete mixtures in an array, various pigments are used in large quantities [2, 3].

The objective of the invention is to reduce the consumption of pigments, increase frost resistance.

The technical result is achieved by the fact that, according to the method, which includes dosing of cement, aggregate, water, antifreeze additives, preparation of concrete mixture, laying of concrete mixture, its hardening at a negative temperature, granules of a pigment-colored cement cooled to a negative temperature are introduced into a concrete mixture dough without antifreeze additives, and after the specified hardening of the concrete mixture, concrete products are kept at a positive temperature until the end of rhenium specified granules. Granules occupy 0.1-10% of the volume of concrete mix.

A method of manufacturing concrete products is illustrated by example.

The components of the concrete mixture are dosed, for example, in the following ratio, kg: cement (Portland cement) 250; aggregate (silica sand for construction work) 750; water 125, antifrosty additive (potash) 10. The concrete mixture is cooled to negative temperatures (for example, -25 ° C).

Prepare a cement paste, including, kg: cement (white Portland cement) 25; water 10; pigment (redoxide) 2. Granules are formed from the cement paste, which are cooled, for example, to a temperature of -25 ° C. It is possible to cool a block of cement paste with its subsequent crushing into granules. Frozen cement paste is durable, only due to frozen water.

Granules are introduced into the cooled concrete mixture, which employ 0.1-10% of its volume. The concrete mixture is placed in a formwork or mold (metal, plastic, plywood, etc.) and left to solidify at low temperatures. At the same time, cement hydration processes occur only in concrete mix, which includes an antifrosty additive, but not granules. Then the concrete product is placed in a positive temperature, for example, + 20 ° C. Under these conditions, the hydration process in the cement paste begins. Concrete products withstand conditions of positive temperature until the curing of the granules. Then the concrete products are machined (sawn into slabs, grinded, ground, polished). As a result, on a gray background the surface of concrete products receive red inclusions. Frost resistance of products increases by 10%.

The proposed method allows to obtain a "spotty", including multi-color, coloring of concrete products, to reduce the consumption of expensive pigments.

Information sources

1. Afanasyev A.A. Concrete works. - M .: Higher. school, 1991. - S.232-250.

2. Gershberg O.A. Technology of concrete and reinforced concrete products. - M .: Stroyizdat. 1965. - P.77, 78, 136.

3. Chernykh V.F. Wall and decoration materials. - M.: Rosagropromizdat, 1991. - P.86-93.

Claims (2)

1. A method of manufacturing concrete products, including dosing of cement, aggregate, water, antifreeze additives, preparation of concrete mixture, laying concrete mixture, its hardening at a negative temperature, characterized in that the granules of the colored are cooled to a negative temperature and injected pigment cement dough without antifreeze additives, and after the specified hardening of the concrete mixture, concrete products are kept at positive temperatures until finished hardening said granules. 2. The method according to claim 1, characterized in that said granules occupy 0.1-10% of the volume of the concrete mixture.