SU687023A1 - Concrete mixture - Google Patents

Description

I

The invention relates to compositions of concrete mixtures containing modifying additives.

A known concrete mixture containing cement aggregate, water, and an accelerator N82804 in quantities of 1.2% and 3%.

Closest to the proposed mixture is a concrete mixture containing cement, aggregate, ammonium chloride, sodium sulfate and water. The additive is introduced in an amount of about 5% by weight of cement with a ratio of the components, respectively, 0.3: 0.7 2.

However, this additive does not allow to increase the strength of the concrete before and after steaming. The aim of the invention is to increase the strength of concrete after heat treatment and subsequent hardening.

This is achieved by the fact that the concrete mixture contains cement, aggregate, ammonium sulphate sodium chloride and water in the following ratio, wt.%:

Cement8,000-25,000

Zapolitel51,000-89,000

Ammonium chloride 0.032-0.375

0.064-0.75

Sodium Sulphate Else, Water

The proposed complex additive allows the directional influence on the hydration of the hardening of cement stone and concrete during steaming and to obtain optimal hardening structures. The presence of NH4CI in the mixture makes it possible to enhance the effect of increasing strength due to sodium sulfate immediately after steaming and especially at 28 days of age. In addition, gaseous ammonia released during interaction with cement forms the fine-porous structure of cement paste, which makes it possible to predict a higher frost resistance of concrete. The ratio between the components of the additive depends on the mineralogical composition of the cement used.

The additive is introduced into the concrete mix while mixing.

In tab. 1 shows the compositions of the proposed and known concrete mixes.

The composition of the mixture, wt.%

Components proposed famous

13.5

13.5 30.0 30.0. 49.507 49.6825 ammonium 0.081

0.02025 sodium 0.162 0.04725

675 6.7

In tab. 2 shows the compressive strength of ар steamed Ofaztsov obtained from the proposed stiff mixtures.

table 2

Concrete mixture containing cement, aggregate, amkyuni chloride, sodium sulfate water, characterized in that, with a crack to increase the strength of concrete, 1 is less than the heat and moisture treatment, and during subsequent hardening, these components, with the following ratio, weight:

Cement

8,000-25,000 51,000-89,000 Aggregate Ammonium chloride 0.032-0.375 Sodium sulfate 0.064-0.750

Water Else.

Sources of information taken into account by the expert

1.Maksimov V.G. On the effect of sodium sulfate additives on the strength of shotcrete.

Building and architecture of Uzbekistan, N 3, 1972, p. 12-14.

2. Voznesensky, V. A., Kryzhanovsky, I. I., Planning of Experiments in the Selection of Effective Additives of Concrete Quality Controllers. —Investigation of Concrete and Reinforced Concrete Structures by Experimentally Static Methods, Chisinau, Shtiishi, 1972, p. 6-28.