SU893970A1 - Method of producing concrete articles - Google Patents

Description

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The invention relates to building industry and can be used at house-building factories in concrete plants for concrete products and concrete and concrete products.

And there is a natural way of making free-standing and reinforced concrete products and my own designs with heated concrete mixture, subsequent vibration and heat treatment. To reduce the heat treatment and increase the dnoTHOCTH of concrete, the betsuyu mixture put into molds is compacted, and then heated, for example, by electric current for 1 min-30 min to ZO-98 ° С | and then immediately re-condense the HZ.

The known method does not provide an excessive amount of water and entrapped air from a freshly laid concrete concrete wall, which does not allow to obtain a sufficiently dense concrete structure.

The closest to the present invention is the method of concreting concrete weeds, including heating the concrete mix, laying it into a mold, vibrating compaction with simultaneous surface heating and subsequent heat treatment C2,

The disadvantage of the known method is that with a constant vibro-compaction mode, it is not ensured that sufficient water is evaporated out of excess water and the strength of the product is not observed.

The purpose of the invention is to increase the strength of the product.

IS

This goal is achieved by the fact that in the method of making concrete products, including heating the concrete mix, laying it into a mold, vibrating compacted with simultaneous surface heating and subsequent heat treatment, compaction takes place cyclically in 20-60 seconds with an interval of 4-5 min for 15 -25 min with an increase in the frequency of oscillations. From 50-55 to 65-70 Hz in ampites from 0.2-0.3 to 0.7-O, 8 mm

The method is carried out as follows.

Forms with a laid concrete mixture are installed under the thermal board (panel with generators of thermal radiation located on it), and the distance from the surface of the product to the thermo-furnace is taken to be 5-1 O cm so as to provide surface heating of the product to 90-100 ° C. Then the product subjected to joint exposure to surface heating and Ishslichesky vibro-compaction of 20pO for 15-25 minutes every 4-5 minutes with an increase in frequency / vibrations from 5O-55 to 65-7O Hz and amplitudes from O, 2-O, 3 to O , 7-Oh, 8 mm. The product is then sent for heat treatment.

When combining periodic vibrating of concrete with surface heating of the product, moisture and air in the concrete mix under the action of vibration rushes to: 1 1 of the surface of the product, and the supply of heat to this surface promotes the evaporation of excess water, i.e. increase the stiffness of concrete. Therefore, it is necessary during this time (work to change the intensity of the screen).

Samples of the size O2O2O cm are made of heavy concrete mix Mi-4OO.

Example. With the initial stiffness of the concrete mixture of 25 seconds, vibration compaction with simultaneous exposure to surface heating was carried out 5 times (cycles) in 5 minutes for 30 seconds.

The vibration mode of the first and second cycles is an amplitude of 0.35 mm, a frequency of 5O Hz} of the third and fourth cycles is an amplitude of 0.5 mm, and the frequency of 5O Hz.

Example 2. At an initial hardness of a concrete mix of 25 s for compaction with simultaneous exposure to surface heating, it is performed 5 times (cycles) after 5 min in 30 s.

The mode of bibration of the first and second nick is 0.2 mm amplitude, frequency is 7 O Hz; the third and fourth - amplitude O, 3 mm, frequency 70 Hz; The fifth cycle - amplitude 0.5 mm, frequency 70 Hz.

Example 3. With an initial concrete mixture stiffness of 25 s, vibration compaction with simultaneous exposure to surface heating takes 5 cycles in 5 minutes, 30 seconds each.

The vibration mode of the first and second cycles is the amplitude O, 35 mm, frequency 5O Hz; the third and fourth - the amplitude of 0.5 mm, frequency 50 Hz; The fifth Shosh - amplitude 0.5 mm, frequency 70 Hz.

The molded specimens are heat treated.

The test results of prototypes are presented in the table.

According to the studies, the products have a higher potential and durability.

The proposed spos (it allows to reduce the consumption of 1umenta by 1O-15%.

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Claims (1)

Invention Formula A method for manufacturing a concrete LII, including heating the concrete mix, laying it into a mold, vibrating compaction with simultaneous surface heating, and subsequent heat treatment, characterized in that, in order to improve the strength of the product, 55 5 min for 15-25 min with increasing often58939706 you, koebyniyot 5O-55 to 65-7O Hz1. USSR author's certificate and amplitudes from O, 2-O, 3 to 0.7-O, 8 mm. No. 239096, cl. C O4 To 15/00 1969. Sources of information, 2, USSR Copyright Certificate taken into account during examination № 405845, cl. From 04 to 41 / ZO, 1970.