RU2459785C1 - Waterproofing mixture - Google Patents

Abstract

FIELD: chemistry.

SUBSTANCE: invention relates to waterproofing dry construction mixtures with use of chemically active components to treat concrete surface exposed to water. The waterproofing mixture for treating concrete surface contains the following in wt %: portland cement 87.5-89.0, sodium sulphate 8.8-10, organosilicon liquid GYUK-11 1.0-2.0, superplasticiser S-3 0.5-1.2.

EFFECT: high water impermeability, 9-12% increase in surface layer density, more than three-fold increase in adhesion strength, reduced formation of efflorescence on the treated surface, reduced shrinkage of the waterproofing composition with respect to the treated surface which enables to prevent formation of cracks.

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Description

The invention relates to waterproofing dry construction mixtures using chemically active components for surface treatment of concrete exposed to water.

A known composition for waterproofing porous concrete surfaces, including in wt.%: Sodium carbonate 7-12; citric acid 3-6; Portland cement 20-25, sand fractions up to 600 microns rest. The composition is applied to the concrete surface (Patent RU 2325370, C04B 41/65. Composition for waterproofing porous concrete surfaces, 10/06/2006).

The disadvantage of this invention is the formation of efflorescence on the treated surface and greater shrinkage of the waterproofing composition compared to the concrete surface, which leads to the formation of surface cracks.

The known composition of the waterproofing mixture for surface treatment of concrete. The composition includes, wt.%: Sodium carbonate 30,0-51,3; sodium sulfate 20.5-40.0; sodium chloride 0.4-0.5; sodium nitrate 14.5-27.7 and calcium nitrate 0.1-15.0. The composition is mixed with cement-sand mortar containing quicklime and applied to the concrete surface (Patent RU 2052413, C04B 28/04. The composition of the additive "Kalmatron" for concrete mix or surface treatment of concrete, 01/20/1996).

The disadvantage of this composition is the low degree of water resistance of the treated concrete, the small penetration depth of the concrete body is about 15 cm, the low cubic, prismatic and adhesive strength, as well as the appearance of efflorescences on the surface of the treated concrete.

The first objective of the invention is to increase the water resistance, density of the treated concrete.

The second task is to reduce the formation of efflorescence formed on the surface of the treated concrete, to reduce the shrinkage of the waterproofing composition in relation to the treated concrete surface, which eliminates the formation of cracks on the treated surface.

A third object of the invention is to increase the adhesion strength to old concrete.

The result is achieved in that the waterproofing mixture for treating the concrete surface, consisting of Portland cement, sodium sulfate, according to the invention, additionally contains silicone liquid GKZH-11%, superplasticizer C-3, in the following ratio of components, wt.%:

Portland cement 87.5-89.0 sodium sulfate 8.8-10.0 silicone fluid GKZH-11 1.0-2.0 superplasticizer C-3 0.5-1.2.

To obtain a waterproofing mixture, Portland cement, PC 500-D0 without additives, GOST 10178-85, chda sodium sulfate (pure for analysis), GOST 4166-76, silicone liquid GKZh-11 - TU 6-02-696-72, superplasticizer S-3 are used - TU 254-1298281-031-90.

The waterproofing mixture is prepared as follows: sodium sulfate is closed in water and mixed thoroughly until sodium sulfate is completely dissolved, after which organosilicon liquid is added to the resulting solution and thoroughly dissolved in the solution; Portland cement is mixed with a superplasticizer and the resulting dry mixture is sealed in the above solution. The resulting waterproofing mixture is thoroughly mixed until a homogeneous consistency is obtained, after which it is applied to a wet concrete surface. The mixture can be applied by brush or trowel, depending on the amount of mixing water.

Possible options for a waterproofing mixture are given in table 1, wt.%:

Table 1 Component Composition 1 Composition 2 Composition 3 Portland cement 89.0 88.25 87.5 sodium sulfate 8.8 9,4 10.0 silicone liquid GKZH-11 1,0 1,5 2.0 superplasticizer C-3 1,2 0.85 0.5

Physico-mechanical characteristics of the waterproofing mixture are given in table.2.

table 2 Indicator Waterproofing mixture Kalmatron composition 1 composition 2 composition 3 Water resistant W20 W22 W26 W12 Adhesion to concrete surface, bending strength of glued samples, MPa 3.3 (concrete failure) 3.1 (concrete failure) 3.5 (concrete failure) 1,1 (seam fracture) Density increase, at 28 days in comparison with control samples 9-12% 9-12% 9-12% There is no data Rolling time, min Start fifteen fifteen fifteen There is no data end 40 40 40 There is no data Shrink Education
cracks, age of samples 28 days - - - cracks up to 0.1 mm

Thus, an increase in water resistance to W26 was achieved, an increase in density by 9-12%, adhesive strength increased by more than 3 times. The introduction of GKZh-11 and S-3 superplasticizer into the composition of organosilicon liquid significantly reduced the formation of efflorescence on the treated surface and the shrinkage of the waterproofing mixture deposited on the concrete surface, with cubic strength reaching 190 MPa, prismatic strength 110 MPa, and bending strength 5.6 MPa.

Claims (1)

A waterproofing mixture for treating a concrete surface containing Portland cement, sodium sulfate, characterized in that it additionally contains GKZh-11 organosilicon liquid and C-3 superplasticizer in the following ratio, wt.%:
Portland cement 87.5-89.0 sodium sulfate 8.8-10.0 organosilicon liquid GYUK-11 1.0-2.0 superplasticizer C-3 0.5-1.2