SU1578242A1 - Method of erecting concrete under hot climatic conditions - Google Patents

Abstract

The invention relates to the construction of concrete pavements and can be used in the construction of roads, airfields and in other industries. The purpose of the invention is to accelerate the commissioning of the coating. In the method of erection of the coating, including the distribution and compaction of the concrete mix with mineral in the ground, the covering of the coating with a polymer film and the subsequent surface treatment of the coating with the film-forming composition, the coating is kept in air for three days before covering it, and under the film for seven days, then the coating is cleaned with a mechanical brush and a film-forming composition is applied to the surface. In this case, the coating is carried out from a rigid concrete mixture on a slow-hardening slag in the holding. As the film-forming composition using a 20% solution of polyethylsiloxane emulsion. 1 hp f-ly.

Description

The invention relates to the construction of concrete pavements and can be used in the construction of roads, airfields and in other areas of construction.

The aim of the invention is to accelerate the commissioning of the coating.

The method is carried out as follows.

Rigid concrete mix on the basis of slow-hardening slag is placed on the prepared base, for example, using concrete distribution machines, universal laying machines, graders, after which it is compacted by repeated passes of road rollers. Stiff concrete

the mixture is characterized by a zero draft of the cone and a workability of 156-214 seconds. The flow of water is 6-8%.

Slag-in-slag is obtained by joint grinding of granulated blast-furnace or phosphorus slag with visitors, for example, cement dust, in a ratio of 9: 1 or 8: 2.

After compaction, the concrete coating is kept at ambient air temperature for 3 days, after which a polymer film, for example, polyethylene, 0.2 mm thick, the edges of which are covered, is rolled over the entire width of the coating for sealing the roadsides with soil. With

resistant weather conditions that are typical for the southern regions of the country, the coating is kept under the polymer film for 7 days for concrete to set on the osmol of a slow-hardening slag that holds the required strength, then the film is removed, and the surface of the coating is cleaned with a mechanical brush mounted on the washer to remove unbonded crushed stone from the surface. After cleaning, a film-forming composition is applied to the surface of the coating, for example, a 20% solution of polyethylsiloxane emulsion. The filling of the film-forming composition is carried out using known machines, such as self-impacting machines. After the formation of the film, traffic is opened along the road.

When pre-curing the concrete at ambient temperature, the degree of slag hydration into the material in the surface layer of the material increases due to the formation of dense hydrated shells when the upper layers of concrete evaporate from gel-like calcium hydrosilicate of the CSH type. These hydration shells further prevent the evaporation of moisture from the inner layers of concrete.

tones, and the resulting vapor pressure increases the degree of hydration in the person. When preliminary held, evaporation of moisture from concrete occurs very slowly due to its limited content and very dense packing of particles of a rigid concrete mix. For 3 days, the concrete warms up to the ambient temperature, a small amount of evaporated moisture is not able to adversely affect the quality of the coating, since some of the excess moisture in the free state in the pores of the concrete evaporates.

During the period of solar heating of concrete protected by a polymer film,. Accelerated structure formation and concrete curing under the action of solar energy occurs. Evaporation of moisture practically does not occur, since free moisture has already evaporated, and the associated moisture can evaporate only at very high temperatures (up to 100-120 ° C), therefore no condensation occurs on the inside of the polymer film and the concrete is good. warms up.

The great influence on the process of structure formation and the rate of concrete strength build-up pump the optical properties of the polymer film, depending on its thickness. The thinner the film, the more solar energy

goes through it. In the proposed method, a non-stabilized polyethylene film with a thickness of 0.2 mm is used.

To ensure concrete hardening

5 on the basis of a slow-hardening slag in a binder, which has the ability to gain strength for a long time, after removing the polymer film to prevent the evaporation of water from the coating, it is necessary to treat its surface with a film-forming composition, in the proposed method with a 20% solution of loliethylhydride siloxane emulsion,

5 produced by the chemical industry organosilicon compounds. The polyethylsiloxane emulsion (CE-30-04) is manufactured by the chemical industry of organosilicon compounds and is subject to the specification of Specifications TU 6-02-816-78. Physico-mechanical properties of the emulsion KE-30-04 are given in table 1.

When the emulsion is applied to the concrete surface, the liquid medium restores the free moisture in the upper layers of concrete, which evaporated during the pre-curing period of the coating in air without protection with plastic wrap, and the emulsion phase envelops the concrete surface, creating a thin impermeable layer on the surface. It is optimal to apply a 20% aqueous solution of a polyethylhydrosyloxane emulsion to the surface; this consumption ensures a further curing of the concrete without decreasing its intensity during hardening in the open air.

PREMIENTAL OF THE CHEMKENT Phosphorus Plant 5 with a chemical composition shown in Table 2 was used as a slow-hardening mortar in a mixture.

Made. Concrete mixtures had the compositions given in tabl.3o

0

five

0

five

50

The strength characteristics of concrete at different periods of hardening, depending on the storage conditions of the samples, are given in Table 4.

The test results show that the use of the proposed method allows for 10 days to reach penetrability equal to the strength of concrete on slow-hardening slag in the gnarled, hardened for 90 days under standard temperature-humidity conditions, which allows to speed up the commissioning of the coating, as well as reduce the cost construction process.

Claims (2)

1. A method of erecting a concrete pavement in a harsh / climatic climate, including distribution and compaction 57824 6 Concrete smog on the mineral in the susceptible, covering the coating with a polymer film and subsequent treatment of the film-forming composition from the surface, in that, in order to speed up the commissioning of the coating, the coating is kept in the air for 3 days before covering it, and under the film - for 7 days, after which the film-forming base was applied to the surface of the coating, while the coating was made of rigid concrete mixture on a slow-hardening slag in the grit. 2. The method according to claim 1, similar in that a 20% solution of polyethylsiloxane emulsion is used as the film-forming composition. 15 20 Table 1 The name of indicators Norms one with g, White homogeneous liquid 2D 25 Continuation of table 1 The reaction medium (pH 25% - aqueous solution) The content of silicon Active hydrogen content,% Hydrophobic ability, not less g 5.5-7 16.5-19.5 0.6-0.8 table 2 15782428 Table 3 27 24 21 65 68,5 72 765 one 1.5 Editor A.Makovska Compiled G. Can tire Tehred L. Oliynyk Proofreader E. Lonchakova Order 1894 Circulation 459 VNIIPI State Committee for Inventions and Discoveries at the State Committee on Science and Technology of the USSR 113035, Moscow, Zh-35, Raushsk nab. 4/5 Production and publishing plant Patent, Uzhgorod, st. Gagarin, 101 28 64 25 22 68 7 72 6 Table 4 Subscription