RU2361833C2 - Complex modifier of concrete with polyfunctional action (versions) - Google Patents

Abstract

FIELD: construction.

SUBSTANCE: additives for concrete mixes based on different binders may find application in manufacture of structural units, plates, panels, heat insulating boards and tiles, finishing plates and plaster for finishing of facades, floor leveling, heat insulation of ceilings and roof and manufacture of other concrete and reinforced concrete products. Complex modifier of concrete with polyfunctional action includes the following components, wt parts: sodium tripolyphosphate - 1.0-4.0, amorphous silica or quartz sand - 0.3-1.5, calcium hydroxide - 65.0-89.0, plasticising additive selected from the following group: sodium polycarboxylate, sodium salts of sulfonated naphthalene formaldehyde and melamine formaldehyde resin - 10.0-37.0. According to another version of invention realisation, complex modifier of concrete with polyfunctional action includes the following components, wt parts: aqueous solution of sodium tripolyphosphate - 3.0-3.5, aqueous solution of plasticising additive selected from the following group: technical sodium lignosulphonate, sodium salts of sulphurised naphthalene formaldehyde and melamine formaldehyde resin, sodium polycarboxylate - 2.0-4.0, potassium polymethyl siliconate - 2.0-2.5, water - 0-3.0.

EFFECT: improved strength and water resistance of concretes based on different binders, lower water absorption.

2 cl, 1 tbl, 27 ex

Description

The invention relates to building materials, in particular to the compositions of complex additives for concrete mixtures based on various binders, as well as mortars, including dry concrete and mortar mixtures, and can find application in the building materials industry, in the manufacture of concrete and reinforced concrete products.

Various chemical additives are known, in particular plasticizing and water-reducing, used in various concrete mixtures, mortars, which allow you to control the mobility and workability of concrete mixtures, to control the duration of mobility and the speed of setting and hardening, by improving the flow rate of water to improve the quality characteristics of concrete (strength , impermeability, durability, etc.).

These additives are obtained both in solid form (solid modifiers) and in the form of solutions.

Known plasticizing additives based on lignosulfonates. Being a by-product of pulp and paper production, lignosulfonates well plasticize cement systems and, as a rule, provide a low rate of loss of mobility. Conversely, high dosages of lignosulfonates significantly slow down the setting of cement systems, providing increased viability (i.e. maintaining high mobility). For example, complex additives for concrete mixtures using a plasticizer — sulfite-yeast mash (SDB), containing up to 82% lignosulfonates and therefore having another name — technical lignosulfonates (LST) (Concrete and Reinforced Concrete magazine, 1978), are known. , No. 7, p. 26, “Complex chemical additives using caustic soda”, authors I. M. Glushko, I. M. Sviridenko, V. P. Zhiltsov).

The use of complex additives consisting of caustic soda, plasticizing (SDB) and air-entraining additives is accompanied by a slowdown in cement hydration, which reduces the strength of concrete and affects the quality of structures.

The most promising is the use of cement and concrete plasticizer based on technical lignosulfonates in the form of modified products.

Known plasticizing additive for concrete mix, consisting of technical lignosulfonate with a mineral adsorbent, which is used as peat ash (patent RU No. 2018496, 08/30/94).

The disadvantage of this additive is the low quality of the plasticizer due to the instability of the composition.

Known liquid complex additive for concrete mix (A.C. SU 1636378, 09/23/91), including technical lignosulfonates, phosphoric acid salt and water in a certain ratio.

The disadvantage of this additive is the low strength of concrete and the disadvantages inherent in liquid additives.

Known additive for concrete mixture, including the waste of caprolactam production and technical lignosulfonate, which allows to improve the quality indicators of concrete and products based on it (patent RU No. 2209792, 08/10/2003)

The disadvantage of this additive is also the low strength of the resulting concrete and concrete products.

Significant disadvantages of the mentioned lignosulfonate additives are their inherent slowdown in cement hydration and additional air entrainment into the concrete mixture, leading to a noticeable decrease in concrete strength.

Synthetic superplasticizers based on sulfonated melamine and naphthalene formaldehyde resins, as well as polycarboxylate type additives to a much lesser extent slow down the hydration of Portland cement and the formation of cement systems and practically do not involve additional air in the concrete mixture, which leads to higher mechanical characteristics of concrete. At the same time, concrete mixtures with these additives are characterized by a quick loss of mobility; the pot life of cast concrete mixtures with S-3 superplasticizer usually does not exceed 45 minutes. Such an indicator is insufficient for ready-mixed concrete transported over considerable distances, which limits the use of these plasticizers in monolithic concrete.

Improving the viability of concrete mixtures, as well as their other properties, can be achieved through the use of complex modifiers of multifunctional action.

It is known to obtain a complex additive for concrete and mortar by mixing components — a naphthalene formaldehyde type plasticizer with technical lignosulfonates, and a complex additive is known to be a mixture of the specified plasticizer with the indicated lignosulfonates (Auth. St. No. 1270150, 10/18/2000).

It is known to obtain a powdered complex additive for concrete and mortar, including mixing aqueous solutions of technical lignosulfonates and a modifier, which is used as an enzyme preparation — an alkaline protease with a pH of 9-12, followed by isolation of a 10 · 10 ³ fraction using polymer membranes from the resulting mixture. -20 · 10 ³ and drying the resulting solution in a fluidized bed at 72-82 ° C to the final product, and a powder complex additive for concrete and mortar obtained by the specified method both (patent RU No. 2114082, 06/27/88).

The known method for producing a powdered complex additive is relatively complicated, as a result of which the cost of the additive is high.

A complex additive is known from RU 2273013, which is used in cementitious cementitious compositions for the manufacture of quick-hardening mortars and concrete.

This complex cement binder additive contains S-3 superplasticizer, sodium sulfate, technical lignosulfonate water-reducing agent, aluminum sulphate sealant and antifreeze additive - potash, in the following ratio, wt.%: S-3 14-28 superplasticizer, sodium sulfate 14 -28, technical lignosulfonate 3-7, aluminum sulfate 14-28, potash 30-50. The technical result is a reduction in the water demand of mortar and concrete mixtures, an increase in the hardening speed and strength of mortars and concrete, but the strength properties do not meet the increased requirements for them.

From RU 2292316, January 27, 2007, the Linamix P90 complex additive for concrete and mortar is known to be obtained by mixing aqueous solutions of technical lignosulfonates — LST and a modifier, followed by drying the resulting solution in suspension, using C- plasticizer as a modifier 3, and the specified mixing is carried out in a ratio of 1: 1 to 1: 3 on dry matter to obtain a 2.5% aqueous solution with a pH of 7-11, and drying is carried out in a stream of flue gas in a fluidized bed dryer with a fluoroplasto filler howling crumb - at the temperature of the flue gas at the inlet 160-230 ° C, in the fluidized bed 120-160 ° C and at the outlet 110-140 ° C with continuous unloading of the obtained additive through a group of cyclones into the hopper.

The method of obtaining this additive is quite complicated.

It is known to manufacture modifying additives for concrete mixtures, including mixing a mineral filler, a plasticizer and an inorganic hardening accelerator, in which a mixture of aqueous solutions of a plasticizer and an inorganic hardening accelerator is prepared before mixing, which is thoroughly mixed with a mineral filler and then dried at a temperature of 105-150 ° C to a residual moisture content of 10-14%, the resulting product is granulated in a disk or drum granulator. The additive thus obtained for preparing the concrete mixture is introduced in an amount of 10-20% by weight of cement, while the ratio of the components of the complex additive is, wt.%: Mineral filler (71.4-98.0), plasticizer (1.5-14 , 3), inorganic hardening accelerator (0.5-14.3) (RU 2070171, 1996). The disadvantage of this method is the complexity of the process, high energy consumption for the drying process, the organization of a joint process for the manufacture of modifying additives and the preparation of concrete mix. It excludes the possibility of producing pigmenting additives, which can be used in the paint and varnish industry for building materials and the production of colored cement mortars, ceramics, etc.

Another complex additive for concrete mix is known from RU 2278837, 06.27.2006, including technical lignosulfonate and trisodium phosphate, the amount of which is 0.4% by weight of cement, contains wt.%: Lignosulfonate 30-50, trisodium phosphate subjected to mechanical activation 50-70, moreover, it preferably contains lignosulfonate 50, trisodium phosphate 50, as well as at least one component: natural zeolite, silica, waste products of zeolite, sodium dichromate, potassium dichromate, sodium thiosulfate in an amount of up to 3 wt.%, which is subjected to mechanoactivity ovation to a particle size of not more than 10 microns, preferably together with trisodium phosphate, and technical lignosulfonate granular. However, this additive does not sufficiently provide high strength properties of concrete products.

A complex concrete modifier is known from RU 2288197, November 27, 2006, containing a dispersed mineral component, including rock or its mixture with fly ash and / or gas treatment products from furnaces smelting silicon-containing alloys, and a plasticizing additive, while the dispersed mineral component as a rock includes heat-treated kaolin and gypsum, and the modifier may further include calcium hydroxide, in the following ratio, wt.%:

Dispersed Mineral Component 80-98 Plasticizing additive 2-20 Calcium hydroxide 0-10

which ensures the presence of the following oxides in the modifier at the following content, wt.%:

SiO ₂ 20-66 Al ₂ O ₃ 4-27 SO ₃ 4-26 CaO 3-22 H ₂ O 3-12

Moreover, this complex additive as a plasticizing additive contains a salt of polycondensate β-naphthalene sulfonic acid and formaldehyde, and / or a salt of lignosulfonic acid, and / or polycarboxylate.

However, this well-known complex additive also does not provide the necessary level of properties for strength properties and water resistance.

This invention is selected as the closest analogue of the claimed invention in technical essence.

An object of the invention is to increase the strength properties of concrete based on various binders (gypsum, Portland cement, mixtures thereof, etc.), increase water resistance, reduce water absorption.

The stated technical problem is achieved by the claimed group of the invention, which includes a dry (solid) complex modifier of multifunctional action and a complex modifier of multifunctional action in the form of a solution.

So, the solution of this problem is achieved by a complex modifier of concrete of multifunctional action, including a mineral component, calcium hydroxide and a plasticizing additive containing amorphous silica or quartz sand grade PB-150-1 of a fraction of 0.1-1 mm as a mineral component according to GOST 22551-77 a plasticizing additive selected from the group consisting of sodium polycarboxylate, sodium salt of sulfonated naphthalene formaldehyde resin, sodium salt of sulfonated melamine formaldehyde resin and additionally sodium tripolyphosphate in the following ratio, wt.h:

Sodium Tripolyphosphate 1.0-4.0 Amorphous silica or silica sand 0.3-1.5 Calcium hydroxide 65.0-89.0 The above plasticizing additive 10.0-37.0

The obtained modifier according to the invention is made in the form of a solid modifier, i.e. in the form of a dry powder.

The stated technical problem is also achieved by another modifier, which is another embodiment of the invention of the claimed group.

So, the solution of the problem of the invention is also achieved by another complex modifier of concrete of multifunctional action, including an aqueous solution of a plasticizing agent selected from the group including technical sodium lignosulfonates, sodium salt of sulfonated naphthalene formaldehyde resin, sodium salt of sulfonated melamine formaldehyde resin, sodium polycarboxylate and

An aqueous solution of sodium tripolyphosphate 3.0-3.5 An aqueous solution of the above plasticizing additives 2.0-4.0 Potassium Polymethylsiliconate 2.0-2.5 Water 0-3.0

This modifier is made in the form of a solution.

So, the complex modifier of concrete of multifunctional action obtained by the claimed invention (group of the invention) is made either in the form of a dry powder (one embodiment of the invention) or in the form of a solution (composite solution).

In the claimed group of the invention, upon receipt of the modifier as a plasticizing additive, use:

- technical lignosulfonates in the form of sodium salts

- sodium polycarboxylate, for example, Visco Crete-105 Pulver additive, which is a copolymer based on oxyethylene and oxypropylene compounds, as well as the Melflux 164IF brand;

- sodium salt of sulfonated naphthalene formaldehyde resin (polycondensation product of naphthalenesulfonic acid and formaldehyde);

- Sodium salt of sulfonated melamine formaldehyde resin, for example, brand Melment F10 and its analogues.

The polycondensation products of naphthalene sulfonic acid with formaldehyde, as well as the polycondensation products of sulfimethylated melamine with formaldehyde, are described in the monograph (Ramchandran BC Additives in Concrete, M., Stroyizdat, 1988, pp. 372-373 and Hattorn K. Development of new plasticizers for high-strength concrete, K Gijutsu, 1976, v. 29, No. 8, pp. 71-77).

The following are specific examples illustrating the claimed invention, but not limiting it. These examples describe the preparation of variants of a complex modifier of concrete of multifunctional action both in the form of dry powder and in the form of a solution, and also illustrate their use.

These modifiers according to the invention are intended for the manufacture of dry construction mixtures for general use using gypsum binder or Portland cement, as well as the widespread use of local building fillers and industrial wastes, and, in particular, they are intended for;

1. preparation of concrete solutions based on:

- gypsum binder;

- cement;

- a mixture of gypsum binder and cement used for monolithic housing construction;

2. manufacturing structural wall parts:

- blocks;

- plates;

- panels;

3. facades and interior walls:

- finishing plates;

- plaster;

4. floor leveling;

5. insulation of ceilings and roofs;

6. heat insulating products:

- plates;

- tiles.

Modifiers are made in the form of dry powders or composite solutions.

Examples 1-15 illustrate dry modifiers, and examples 16-26 illustrate the preparation of the complex modifier according to the invention in the form of solutions.

EXAMPLE 1. In the mixer-activator with an adjustable rotor speed of 0 to 100 m / s place 3.0 wt.h. sodium tripolyphosphate, 81.5 parts by weight calcium hydroxide, 15.0 parts by weight sodium polycarboxylate and 0.5 parts by weight amorphous silica and stirred at a speed of 30 m / s for 20 s, and then at a speed of 100 m / s for 15 s. The obtained dry modifier is unloaded and tested upon receipt of 6 gypsum concrete samples (30 g of modifier per 1 kg). The average value of the data obtained, the test results are shown in the table "The main properties of concrete samples obtained using the declared modifiers".

EXAMPLE 2. In the mixer-activator with an adjustable rotor speed of 0 to 100 m / s place 2.0 wt.h. sodium tripolyphosphate, 87.2 parts by weight calcium hydroxide, 10.0 parts by weight sodium polycarboxylate and 0.8 wt.h. amorphous silica and stirred at a speed of 50 m / s for 25 s, and then at a speed of 80 m / s for 20 s. Further, as in example 1.

EXAMPLE 3. In the mixer-activator with an adjustable rotor speed from 0 to 100 m / s place 4.0 wt.h. sodium tripolyphosphate, 79.7 parts by weight calcium hydroxide, 16.0 parts by weight polycarboxylate sodium and 0.3 wt.h. amorphous silica and stirred at a speed of 30 m / s for 20 s, and then at a speed of 100 m / s for 15 s. Further, as in example 1.

EXAMPLE 4. In the mixer-activator with an adjustable rotor speed of 0 to 100 m / s place 3.0 wt.h. sodium tripolyphosphate, 81.5 parts by weight calcium hydroxide, 15.0 parts by weight sodium polycarboxylate and 0.5 parts by weight amorphous silica and stirred at a speed of 30 m / s for 10 s, and then at a speed of 100 m / s for 30 s. Further, as in example 1.

EXAMPLE 5. Acted as in example 1. The resulting composite modifier mixture is unloaded and tested on gypsum concrete samples. The dosage of the modifier is 15 g per 1 kg of gypsum binder. Further, as in example 1.

EXAMPLE 6. Do as in example 1. The resulting composite modifier mixture is unloaded and tested on concrete samples, including gypsum binder and Portland cement. The dosage of the modifier is 15 g per 1 kg of gypsum binder. Further, as in example 1.

EXAMPLE 7. In the mixer-activator with an adjustable rotor speed of 0 to 100 m / s place 3.0 wt.h. sodium tripolyphosphate, 81.5 parts by weight calcium hydroxide, 15.0 parts by weight sodium polycarboxylate and 0.5 parts by weight silica sand and stirred at a speed of 30 m / s for 10 s, and then at a speed of 100 m / s for 30 s. The obtained dry modifier is unloaded and tested upon receipt of 6 gypsum concrete samples (10 g of modifier per 1 kg of Portland cement). Further, as in example 1.

EXAMPLE 8. Everything, as in example 7. The resulting composite modifier mixture is unloaded and tested on concrete samples based on Portland cement and gypsum binder (modifier dosage of 10 g per 1 kg of Portland cement). Further, as in example 1.

EXAMPLE 9. As in example 1, placed 3.0 wt.h. sodium tripolyphosphate, 71.0 parts by weight calcium hydroxide, 25.0 parts by weight sulfonated melamine formaldehyde resin in the form of sodium salt and 1.0 wt.h. amorphous silica and stirred at a speed of 30 m / s for 20 s, and then at a speed of 100 m / s for 15 s. Further, as in example 1.

EXAMPLE 10. As in example 1, put 5.0 wt.h. sodium tripolyphosphate, 76.5 parts by weight calcium hydroxide, 18.0 parts by weight sulfonated melamine formaldehyde resin in the form of sodium salt and 0.5 wt.h. amorphous silica and stirred at a speed of 30 m / s for 15 s, and then at a speed of 100 m / s for 15 s. Further, as in example 1.

EXAMPLE 11. As in example 1, placed 2.5 wt.h. sodium tripolyphosphate, 86.0 parts by weight calcium hydroxide, 10.0 parts by weight sulfonated melamine formaldehyde resin in the form of sodium salt and 1.5 wt.h. amorphous silica and stirred at a speed of 30 m / s for 25 s, and then at a speed of 100 m / s for 15 s. Further, as in example 4.

EXAMPLE 12. As in example 1, placed 2.5 wt.h. sodium tripolyphosphate, 86.0 parts by weight calcium hydroxide, 10.0 parts by weight sulfonated melamine formaldehyde resin in the form of sodium salt and 1.5 wt.h. amorphous silica and stirred at a speed of 30 m / s for 25 s, and then at a speed of 100 m / s for 15 s. Further, as in example 6.

EXAMPLE 13. As in example 1, placed 2.5 wt.h. sodium tripolyphosphate, 65.0 parts by weight calcium hydroxide, 37.0 parts by weight sulfonated naphthalene formaldehyde resin in the form of sodium salt and 0.5 wt.h. amorphous silica and stirred at a speed of 30 m / s for 25 s, and then at a speed of 100 m / s for 15 s. Further, as in example 1.

EXAMPLE 14. As in example 1, was placed 1.5 wt.h. sodium tripolyphosphate, 67.5 parts by weight calcium hydroxide, 30.0 parts by weight sulfonated naphthalene formaldehyde resin in the form of sodium salt and 1.0 wt.h. amorphous silica and was stirred at a speed of 30 m / s for 15 s, and then at a speed of 100 m / s for 15 s. Further, as in example 8.

EXAMPLE 15. As in example 1, put 1.0 wt.h. sodium tripolyphosphate, 65.7 parts by weight calcium hydroxide, 35.0 parts by weight sulfonated naphthalene formaldehyde resin in the form of sodium salt and 0.3 wt.h. amorphous silica and stirred at a speed of 30 m / s for 15 s, and then at a speed of 100 m / s for 15 s. Further, as in example 6.

EXAMPLE 16. In the mixer is prepared sequentially 3.5 wt.h. an aqueous solution of sodium tripolyphosphate with a concentration of 35 g / l, 4.0 wt.h. an aqueous solution of sodium polycarboxylate with a concentration of 300 g / l. The resulting solutions are mixed with 2.0 wt.h. potassium polymethylsiliconate and 0.5 parts by weight distilled water. The modifier prepared in this way is tested on 6 samples of gypsum concrete, adding 25 g of modifier and 10 g of hydrated lime for each 1 kg of gypsum binder. A suspension of gypsum binder is poured into molds, which are molded and after hardening of gypsum samples for 2 hours they are tested according to GOST 23789. The results are shown in the table.

EXAMPLE 17. In the mixer is prepared sequentially 3.0 wt.h. an aqueous solution of sodium tripolyphosphate with a concentration of 30 g / l, 4.0 wt.h. an aqueous solution of sodium polycarboxylate with a concentration of 250 g / l. The resulting solutions are mixed with 2.0 wt.h. potassium polymethylsiliconate and 1.0 wt.h. distilled water. Further, as in example 16.

EXAMPLE 18. As in example 16, prepare sequentially 3.5 wt.h. an aqueous solution of sodium tripolyphosphate with a concentration of 40 g / l, 3.5 wt.h. an aqueous solution of sodium polycarboxylate with a concentration of 270 g / l. The resulting solutions are mixed with 2.0 wt.h. potassium polymethylsiliconate and 1.0 wt.h. distilled water. The modifier prepared in this way is tested on 6 samples of gypsum concrete, adding 15 g of modifier and 20 g of hydrated lime for each kilogram of gypsum binder. Further, as in example 16.

EXAMPLE 19. In the mixer, 3.5 parts by weight are prepared sequentially. an aqueous solution of sodium tripolyphosphate with a concentration of 35 g / l, 2.5 wt.h. an aqueous solution of sulfonated melamine formaldehyde resin in the form of sodium salt with a concentration of 500 g / l. The resulting solutions were mixed with 2.0 wt.h. potassium polymethylsiliconate and 2.0 parts by weight distilled water. The modifier prepared in this way is tested on 6 samples of gypsum concrete, adding 40 g of modifier and 25 g of hydrated lime for each kilogram of gypsum binder. A suspension of gypsum binder is poured into molds, which are molded and after hardening of gypsum samples for 2 hours they are tested according to GOST 23789. The results are shown in the table.

EXAMPLE 20. In the mixer prepare sequentially 3.0 wt.h. an aqueous solution of sodium tripolyphosphate with a concentration of 35 g / l, 3.5 wt.h. an aqueous solution of sulfonated melamine formaldehyde resin in the form of sodium salt with a concentration of 500 g / l. The resulting solutions are mixed with 2.0 wt.h. potassium polymethylsiliconate and 1.5 parts by weight distilled water. The modifier prepared in this way is tested on 6 samples of gypsum concrete, adding 30 g of modifier and 25 g of hydrated lime per kilogram of gypsum binder. Further, as in example 19.

EXAMPLE 21. In the mixer is prepared sequentially 3.0 wt.h. an aqueous solution of sodium tripolyphosphate with a concentration of 35 g / l, 2.8 wt.h. an aqueous solution of sulfonated melamine formaldehyde resin in the form of sodium salt with a concentration of 500 g / l. The resulting solutions are mixed with 2.0 wt.h. potassium polymethylsiliconate and 2.2 parts by weight distilled water. The modifier prepared in this way is tested on 6 samples of gypsum concrete, adding 20 g of modifier and 20 g of hydrated lime per kilogram of gypsum binder. Further, as in example 19.

EXAMPLE 22. In the mixer prepare sequentially 3.5 wt.h. an aqueous solution of sodium tripolyphosphate with a concentration of 35 g / l, 2.0 wt.h. an aqueous solution of sulfonated naphthalene formaldehyde resin in the form of sodium salt with a concentration of 600 g / l. The resulting solutions are mixed with 2.0 wt.h. potassium polymethylsiliconate and 2.5 parts by weight distilled water. The modifier prepared in this way is tested on 6 samples of gypsum concrete, adding 40 g of modifier and 35 g of hydrated lime for each kg of gypsum binder. A suspension of gypsum binder was poured into molds, which were unformed and after hardening of gypsum samples for 2 hours was tested according to GOST 23789. The results are shown in the table.

EXAMPLE 23. In the mixer, 3.5 parts by weight are prepared sequentially. an aqueous solution of sodium tripolyphosphate with a concentration of 30 g / l, 2.0 wt.h. an aqueous solution of sulfonated naphthalene formaldehyde resin in the form of sodium salt with a concentration of 650 g / l. The resulting solutions are mixed with 2.0 wt.h. potassium polymethylsiliconate and 2.5 parts by weight distilled water. Further, as in example 22.

EXAMPLE 24. 3.0 parts by weight of a batch are prepared sequentially. an aqueous solution of sodium tripolyphosphate with a concentration of 30 g / l, 3.0 wt.h. an aqueous solution of sulfonated naphthalene formaldehyde resin in the form of sodium salt with a concentration of 650 g / l. The resulting solutions are mixed with 2.0 parts by weight of potassium polymethylsiliconate, and 2.0 parts by weight of distilled water. Further, as in example 22.

EXAMPLE 25. In the mixer prepare sequentially 3.5 wt.h. an aqueous solution of sodium tripolyphosphate with a concentration of 35 g / l, 4.0 wt.h. an aqueous solution of technical sodium lignosulfonates with a concentration of 300 g / l. The resulting solutions are mixed with 2.5 wt.h. potassium polymethylsiliconate. The modifier prepared in this way is tested on 6 samples of gypsum concrete, adding 40 g of modifier and 30 g of hydrated lime for each kilogram of gypsum binder. A suspension of gypsum binder is poured into molds, which are molded and after hardening of gypsum samples for 2 hours they are tested according to GOST 23789. The results are shown in the table.

EXAMPLE 26. In the mixer prepare sequentially 3.5 wt.h. an aqueous solution of sodium tripolyphosphate with a concentration of 35 g / l, 4.0 wt.h. an aqueous solution of technical sodium lignosulfonates with a concentration of 300 g / l. The resulting solutions are mixed with 2.5 wt.h. potassium polymethylsiliconate. Further, as in example 25.

EXAMPLE 27. (prototype) Used for the preparation of gypsum concrete complex modifier containing 44 wt.h. heat-treated kaolin, 44 parts by weight gypsum, 12 parts by weight fly ash and 7 parts by weight sulfonated naphthalene formaldehyde resin in the form of sodium salt. Consumption of the complex modifier 40 g per 1 kg of gypsum binder. Prepared by mixing 1000 g of a gypsum binder and 40 g of a complex modifier and water samples were tested, as in example 26. The results are shown in the table.

The following table summarizes the properties of concrete using the modifiers of the invention.

The main properties of gypsum concrete samples obtained using modifiers Example No. Strength, MPa Water absorption,% Water resistance, K _r compression bend one. 12.0 6.8 2.7 0.98 2. 14.5 8.2 1.7 0.98 3. 12.5 5.3 4.6 0.97 four. 13.6 7.1 4.0 0.88 5. 11.0 5.8 5,0 0.79 6. 12.9 8.9 2,3 0.87 7. 11.0 6.0 4,5 0.90 8. 15.6 8.9 1,0 0.98 9. 11,4 6.7 4.7 0.89 10. 10.8 7.9 3,5 0.88 eleven. 10.9 5.8 3.0 0.87 12. 15.7 9.0 1.8 0.97 13. 10.1 7.8 2.9 0.79 fourteen. 11.8 8.9 2.7 0.80 fifteen. 12.0 7.6 2.6 0.83 16. 20.3 10.8 1.9 0.98 17. 19.8 9.8 2.0 0.97 eighteen. 19.6 9.9 2.1 0.97 19. 16.5 9.0 3.0 0.94 twenty. 15.0 9.0 2.9 0.95 21. 17.7 7.8 3.4 0.90 22. 13.9 7.0 4.9 0.87 23. 13.8 7.6 5,0 0.80 24. 12.9 7.2 4.8 0.83 25. 11.8 6.7 3.8 0.79 26. 11.9 6.5 3.0 0.80 27. (prototype) 5.8 2.0 18.9 0.43 28. (no additives) 5.2 2.9 22.4 0.40

As follows from the table, the complex concrete modifiers of multifunctional action according to the invention both in the form of a dry powder and in the form of a solution provide increased strength properties to concrete (compressive and bending strength), as well as increased water resistance.

Claims (2)

1. A complex modifier of concrete of multifunctional action, including a mineral component, calcium hydroxide and a plasticizing additive, characterized in that it contains amorphous silica or quartz sand as a mineral component, a plasticizing additive selected from the group comprising sodium polycarboxylate, sodium salt of sulfonated naphthalene formaldehyde resin, sodium salt of sulfonated melamine formaldehyde resin, and additionally sodium tripolyphosphate in the following ratio, wt. .:
Sodium Tripolyphosphate 1.0-4.0 Amorphous silica or quartz sand 0.3-1.5 Calcium hydroxide 65.0-89.0 The above plasticizing additive 10.0-37.0 2. A complex modifier of concrete of multifunctional action, including an aqueous solution of a plasticizing additive, characterized in that it contains a plasticizing additive selected from the group comprising technical sodium lignosulfonates, sodium salt of sulfonated naphthalene formaldehyde resin, sodium salt of sulfonated melamine formaldehyde resin, sodium polycarboxylate, and additionally an aqueous solution sodium tripolyphosphate, potassium polymethylsiliconate and water in the following ratio, wt.h .:
An aqueous solution of sodium tripolyphosphate 3.0-3.5 Aqueous solution of the above plasticizing additives 2.0-4.0 Potassium Polymethylsiliconate 2.0-2.5 Water 0-3.0