SU920024A1 - Concrete mix composition - Google Patents

Description

 CONCRETE MIXTURE

t

The invention relates to concrete mixes containing additives, and is intended for use in the construction industry.

A concrete mixture is known that includes cement, fine and coarse aggregates, water, and the addition of sulfanic acid HP.

Closest to the proposed technical essence and the achieved result is a concrete mix in which the condensation product (i-naphthalenesulfonic acid with formaldehyde in the amount of 0, by weight of cement 12 is added as an additive)

A disadvantage of the known mixture is the low strength of the resulting concrete with natural hardening.

The purpose of the invention is to increase the strength of concrete naturally hardening.

The goal is achieved by the fact that a concrete mixture, including cement, fine and coarse aggregate and water, contains as a polycondensate additive a condensation product of an alkali metal sulfonate with formaldehyde in the following ratio of components, wt .:

8.5-24.5

Cement

Small zapol26-3 media

Large zapolto

tjl-SO support

The condensation product of alkali metal sulphonate with formaldehy, 025-0.368 degid Remaining Water

The proposed additive is prepared as follows.

Sodium sulfanate or sulfanilic acid is mixed with a 38% formaldehyde aqueous solution. The resulting mixture is stirred while heating to 70-90 ° C for 2 hours. When condensation of formaldehyde with sulfanilic acid is carried out, the solution after heating is cooled to 2060 ° C and neutralized with an aqueous solution of alkali metal hydroxide (N aOH) to pH 6-7.

The known additive is obtained by mixing p-naphthalenesulfonic acid with an aqueous 38% formaldehyde solution. The reaction mixture is heated to 80 ° C and kept at this temperature for 0.5 hours. Then the mixture is cooled I to room temperature and neutralized with an aqueous solution of sodium hydroxide to a pH of 7. At the same time, 1 m.ch. p-naphthalene sulfonic acids take 0.38 mas. formaldehyde (38th), 0, t9 mac. sodium hydroxide and 1, 2 ma.ch. water.

Portland cement of Volkovysk plant M500 with a normal thickness of 26.5% is used as materials for the preparation of a concrete mix;

eight,

16.7 30.6

5 6, 5 26

quartz sand Zaslavl career with Mk 2.49; crushed granite fraction of 5-20 mm.

The concrete preparation technology is as follows.

The condensation product of an alkali metal sulphonate with formaldehyde in the required amount is fed into the concrete mixer together with the mixing water into a dry mixture of other constituents of concrete. The water added with the additive is subtracted from the total amount of water mixed

The resulting concrete mixtures are tested according to GOST 10181-76 d /) for determining the mobility. Samples are then made - cubes with a 10 cm edge for testing compressive strength.

The compositions of concrete are given in table 1. The composition of the additive is presented in Table 2. The obtained properties of the concrete mix and the strength of the concrete with a normal-wet hardening are indicated after 28 days.

in tab. 3

Table 1

7,479

0.021

0.334 6.666

0.98 7.52

With the proposed addition The amount of additive polycondensate is indicated in

(-naphthalenesulfonic acid

Sulfanilic acid

Sodium sulfanilate

Foryaldehyde

0.38 0.7 1.0 (solution)

TableTable one

eleven

OL

0.5 0.5

Claims (2)

1.5 based on dry matter. . Table 2 99 Natural hardening concrete obtained from the proposed concrete mix has an increased compressive strength. In order to obtain uniformly moving concrete mixes, the proposed additive mix requires less than in the known concrete mix. The concrete mix can be used in concrete technology, where it is required to increase the mobility of the concrete mix or reduce the water-cement ratio, as well as increase the strength of the natural hardening concrete. Concrete mix, including fine cement and large aggregate, water and formaldehyde-based polycondensate additive, characterized in that, in order to increase the strength of the concrete, natural solid, it contains as an additive polycondensate product and alkali metal sulfonate metal with rmaldehyde with the following ratio of components, wt.%: Cement 8.5-2, 5 Fine aggregate Coarse alkali metal sulfonate condensation product from formaldehy, 0.055-0.368 house Water The rest Sources of information, which are considered in the examination 1. The author's certificate of the USSR 90001, cl. S O B 7/35, 1967. 2. US Patent No. 3677780, From Ot To 13/28, 1972.