CS199347B1 - High-speed hardening hydraulic mixture - Google Patents

Description

The present invention relates to a fast setting hydraulic mix. In construction practice, there is often a need for rapid repairs and repairs, for example, to seal leakage water, usually from concrete walls to which water pressure will act on the other side, particularly in places where there are cracks, cracks, or various other damage.

It is known that loose lime greatly accelerates the setting of aluminous cement. It is undesirable when solidifying aluminous cement. Therefore, aluminous cement in normal construction practice should not be mixed with either Portland cement or lime. The mixtures of aluminous cement with quicklime powder harden particularly quickly, so that it cannot be mixed or processed sufficiently well. Despite accelerated solidification, the mixture of aluminous cement and Portland cement or lime cannot be used to seal water outlets due to the slow increase in strength and waterproofing effect, as well as poor mechanical properties.

The above-mentioned drawbacks are solved by the quick-hardening hydraulic composition according to the invention, consisting of a mixture of 100 parts by weight of aluminous cement, 2 to 40 parts by weight of ground lime, preferably 8 in the form of lime hydrate and 0.1 to 5 parts by weight of the anionic sulfonated aromatic or heterocyclic compound or salt.

The composition according to the invention may comprise one or a mixture of two or more anionic compounds conventionally produced, for example, in the form of a mixture of alkylarylsulfonic acids or a mixture of alkylarylsulphonic acids. their salts with different carbons in. alkyl chain.

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It is preferred to use a sulfonated triamine-s-triazine condensate and formaldehyde, for example in the form of a soluble sodium salt.

However, other condensation products of formaldehyde with arylsultonated acids, such as 3- ^{naphthalenesulfonic} acid with formaldehyde, are also suitable.

Said anionic sulfonated organic compounds, by their dispersing effect, after mixing with water, make the ground lime and / or lime hydrate more intimately mixed with the aluminous cement, so that the reaction between them is carried out on a higher interface.

Said ionically active sulfonated organic compounds act as a solidification regulator which slows down its course in the first minutes after addition of the mixing water. This extends the pot life of the fresh mixture, so that it is well applicable in practice. In addition, the addition of the aforementioned sulfonated anionic organic compounds allows a substantial reduction in the amount of mixing water required as a result of its effluent.

At the end of the pot life, the hardening of the rapid-hardening hydraulic composition according to the invention is substantially accelerated, resulting in a faster increase in mechanical strength and a faster waterproofing effect compared to a composition containing only aluminous cement, water and lime or lime hydrate. The mixture according to the invention thus has a substantial shortened time between the loss of processability and the acquisition of the necessary physical-mechanical

properties, especially strength. These properties and effects show next examples; Execution example 1 Commercial assays were used aluminous cement with a share 79% of particles smaller than 45 jum, containing; 48,07% Al ₂ ° 3 5.43% ^Pe 2 ° 3 38,18% CaO 4.50% sieve ₂ 0,04% MgO and ground quicklime, with a proportion of 69% of the particles smaller than 45 µm, which contained 91.5%

CaO.

Aluminous cement and ground lime were used as conventional commercial products, without further grinding. The ground lime complied with CSN 72 2209 Ground lime granulation Article 1 lime ground very fine.

Water doses, listed in Tab. 1 were chosen such that the flowability of the anionic agent mixtures was 1 minute from the time of addition of water equal to or better than that of the comparative mixture containing no anionic agent at a dose of 60 parts by weight water per 100 parts aluminous cement and 25 parts lime. The results obtained in the measurement of the workability of the mixtures since the addition of the mixing water are shown in Tab. First

The results show a much longer pot life of the composition according to the invention compared to the comparative compositions. The required pot life is achieved by selecting the dose and type of anionic compound.

Table 1

Composition of the mixture in parts by weight of an anionic sulfonated aromatic or heterocyclic compound

0.3 parts of alkylarylsulfonic acid mixture

0.8 dl of alkylarylsulfonic acid mixture

0.8 dl of propyl benzene sulfonic acid sodium salt!

Dissolved sodium sulfonated condensate! stopping of triamine-s-triazine with formaldehyde

Comparative mixture without anionic substance

Execution example 2

198 347 workability time clay. lime Water /min./ cement 100 25 38 4 ................... ........................- ................................- 100 25 38 15 100 25 38 10 100 25 38 ¹⁰ ............- and 100 25 50 1? 5 ........ ... ... 60 ² j cement and lime, as in 1 Example 1. Next he was with share 85% of the particles smaller than 45 pm, ob-

Calcium hydrate complies with CSN 72 2247.

In the tests, the water dose was selected in the same manner as in Example 1.

The anionic substances used, as well as the composition of the test mixtures, are shown in Tab. Second

In the tests, 2x2x2 cm specimens were tested for compressive strength after 30 minutes and 1 hour after the addition of water.

The results are shown in Tab. Second

From the results shown in Tab. 2 shows that the hydraulic mixture according to the invention has an order of magnitude of 1 hour higher than comparative mixtures no. 1 and 2, wherein the aluminate cement with water / mixture no. 8 / did not yet have measurable hourly strength.

The effect of the invention is thus that it is possible to achieve a strength of from 2.6 to 8.2 MPa in a very short time - as early as 30 minutes after the addition of the mixing water, while at the same time controlling the necessary pot life as shown in Tab. 1. This also reduces the time from solidification of the fresh mixture to its hardening and obtaining the necessary strength. Such a rapid increase in strength, or the required pot life, could not be achieved with the comparative mix.

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Table 2

cis lo zrně- it Used anionic the compound and its doses in parts by weight Composition in parts by weight Po z nka hlinita- new cement lime hydrate calcium-R th waters strength pressure PO 30 min. in MPa Compressive strength after 1 h in MPa Comparative mixture bes undetectable Poor samples after 1 anionic compound 100, 25 - 62.5 gestative 0.5 30 min. not yet - Nina confirmed the Comparative mixture be: Samples after 30 min. 2 anionic compound 100 25 - 75 0.3 has not confirmed with 1 part al- Γ -------------- 3 kylarylsultónových 100 25 s - 50 2.6 3.9 - acid 4 s with 1 part sodium salt of alkylaryl-100 sultonic acid condensate j with formaldehyde j 25 1 / i _ J ................... ............ r and ! ...... i .................. ! 25 50 · ' 3.8 4.2 - 5 f with 1 part of the sodium salt of a sulfonated trlamino-s-triazine condensate with formaldehyde 100 25 ..................... ₅ 0 4.6 5.1 - 6 _ 1 »_! 100 - ⁵⁰ 8.2 9.9 - 7 and with 2 parts of sodium sulfone. triamine-s-triazine condensate with formaldehyde i 100 - - ... 4 and 34 50 7.1 8.8 - Comparative without lime- s ! Harmful samples 8 on and without anionic- 100 - j - 1 35 - - they were not after 1 h compound 1 1 ................... 1 1 J ....... l ossification

Execution example 3

100 parts by weight of aluminous cement, parts by weight of calcium hydrate and 100 parts by weight of natural siliceous granular material up to 2 mm were mixed with 1.25 parts by weight of sodium salt of sulfonated tr-amino-s-triazine formaldehyde condensate. After adding 65 parts of water, 2x2x2 cm fashion samples were made from the mixture. After 15 minutes from the addition of the mixing water, the test samples had a strength of 2.8 MPa. Further, samples were made from the mixture to test the watertightness so that the mixture was applied at a thickness of 6 mm to a 20 x 20 x 12 µm concrete sample that had previously flowed at a pressure of 0.2 MPa. Twenty-four hours after the application of the mass layer of the present invention, they were again subjected to a water-tightness test, the first 24 hours being under a pressure of 0.2 MPa, and then the water pressure was increased every 24 h at 0.2 MPa. The samples did not overflow even at 1 MPa.

The composition of the invention is readily prepared by mere mixing of the ingredients, wherein by selecting the dose of lime and / or lime hydrate and selecting the dose of an anionic organic compound, the pot life and mechanical strength increase can be controlled within these limits. The addition of 1 to 300 parts by weight of inorganic filler, calculated per 100 parts of aluminous cement, results in a cement saving in the mixture. By selecting a suitable type of inorganic filler and its granules5

199 347 lometry, as well as its doses, achieve the desired rheological properties of the fresh composition when applied to the substrate, and adjust the resulting mechanical properties of the hardened composition.

The composition according to the invention is suitable e.g. for the most diverse repairs and repairs of building constructions, especially where it is necessary to achieve extremely fast mechanical strengths and waterproofing effect.

Claims (5)

OBJECT OF THE INVENTION A quick-setting hydraulic mixture comprising a mixture of 100 parts by weight of aluminous cement, 2 to 40 parts by weight of ground lime and / or lime hydrate and 0.1 to 5 parts by weight of an anionic sulfonated aromatic or heterocyclic compound or a soluble salt thereof. . 2. The composition of claim 1, wherein the anionic compound is alkylarylsulfonic acid. 3. The composition of claim 1, wherein the anionic compound is an arylsulfonic acid-formaldehyde condensate. 4. The composition of claim 1, wherein the anionic compound is a sulfonated condensate of triamine-s-triazine with formaldehyde. 5. A composition according to claims 1 to 5 comprising from 1 to 300 parts by weight of inorganic filler per 100 parts by weight of aluminous cement.