RU2485067C1 - Building mortar - Google Patents

Abstract

FIELD: chemistry.

SUBSTANCE: invention relates to construction materials and can be used as mortar for making penetrating-action waterproof coating. The building mortar contains: portland cement 25-27, alumina cement 8.1-8.3, construction sand with particle size of 0.63 mm 36.0-36.5, dolomite limestone with particle size of 100 mcm 7.9-8.3, bentonite clay additive 0.7-0.8, water 16.2-16.6, and a complex additive 4.1-4.5, with the following ratio of components of the additive, wt %: acrylate copolymer Neolith 23.5-25.5; potassium sulphate 36.0-35.5; 20% silicic acid sol solution with pH 4 38.5-39.0.

EFFECT: high adhesion strength of the waterproof coating to the surface of the concrete base and high strength of the concrete base.

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Description

The invention relates to the field of building materials and can be used to protect and restore concrete surfaces of both operated and newly constructed buildings and structures in civil and industrial construction.

Known mortar containing cement, sand, montmorillon clay with S _beats = 150 m ² / kg, silica fume with S _beats = 2000 m ² / kg, and as an additive CMID and 20% solution of sol of orthosilicic acid with pH 3-4 and water (RU No. 2305671, C04B 41/65, 2006.01).

Known mortar, including cement, sand, sodium nitrate, sodium carbonate, sodium sulfate, calcium chloride, calcium carbide, calcium hydroxide and water (RF №2072335, С04В 28/00, B28B 19/00, E04B 1/64, 27.01. 1997).

The disadvantage of these technical solutions is the insufficient adhesive strength of the waterproofing coating to the surface of the concrete base and the insufficient increase in the strength of the concrete base.

Closest to the claimed mortar is a mortar containing Portland cement, alumina cement, sand for construction fractions up to 0.63 mm, dolomitic limestone with a fraction size of 100 microns, the additive represented by superplasticizer C-3 and magnesium sulfate, and water in the following the ratio of components, wt.%:

Portland cement 26.18-32.18 alumina cement 3.76-, 56 specified sand 37.3-38.3 specified limestone 7.34-9.34 superplasticizer C-3 1.88-2.48 magnesium sulfate, 1.37-1.97 water 16.17-17.17

(RU No. 2373166 C04B 28/00, C04B 111/20, 11/20/2009).

The disadvantage of this technical solution is the insufficient adhesive strength of the waterproofing coating to the surface of the concrete base and the insufficient increase in the strength of the concrete base.

The objective of the invention is the creation of a new mortar, the use of which would achieve a technical result consisting in increasing the adhesive strength of the waterproofing coating to the surface of the concrete base and increasing the strength of the concrete base.

The technical result is achieved by the fact that the mortar, including Portland cement, alumina cement, sand for construction work with a fraction of 0.63 mm, dolomitic limestone with a grain size of 100 microns, an additive and water, additionally contains bentonite clay, and Neolith acrylate copolymer as an additive potassium sulfate and a 20% solution of silica sol with a pH of 4, in the following ratio, wt.%:

Neolith Acrylate Copolymer 23.5-25.5 potassium sulfate 36.0-37.5 the specified solution of silica sol 38.5-39.0

Mortar has the following ratio of components, wt.%:

Portland cement 25-27 alumina cement 8.1-8.3 specified limestone 7.9-8.3 specified sand 36.0-36.5 bentonite clay 0.7-0.8 specified complex additive 4.1-4.5 water 16.2-16.6

Compared with the known mortars, the combination of the well-known components of Portland cement, alumina cement, sand for construction fractions of 0.63 mm, dolomitic limestone with a fraction size of 100 microns with bentonite clay and a complex additive consisting of a copolymer of Neolith acrylates, potassium sulfate and 20 is new % solution of silica sol with a pH of 4.

The use of a complex additive consisting of a copolymer of Neolith acrylates, potassium sulfate and a 20% solution of silicic acid sol with a pH of 4, on the one hand, increases the hydration activity of the mortar used as a waterproofing coating, thereby increasing the number of hydrated phases in the waterproofing used coating, which at the time of formation have increased reactivity, on the other hand, the components of the mortar used for waterproofing coating, sink deep into the concrete base, excite unreacted cement and involve it in new hydration processes, thereby increasing the number of hydrated neoplasms.

Due to the presence in the complex additive of potassium sulfate, the components of the mortar mix penetrate as deep as possible into the concrete base, and the presence in the complex additive of a 20% solution of silicic acid sol sufficiently effectively increases the hydration activity of unreacted cement in the pores of the concrete.

Thus, the increased number of hydrated neoplasms in the waterproofing coating and the appearance of an increased number of hydrated neoplasms in the concrete to be protected leads to the formation of an increased number of contacts at the coating - concrete base interface that arise between the hydrated phases with increased reactivity, especially at the time of formation, which and helps to increase the adhesive strength of the waterproofing coating to the concrete base.

At the filing date, according to the authors and the applicant, the claimed mortar is not known and this technical solution has a world novelty.

The claimed combination of essential features exhibits a new property: an increase in adhesive strength and an increase in the strength of a concrete base.

It is another property of the totality of essential features that is not equal to the known properties of the distinguishing features that allows us to recognize this totality as compared to the known ones in science and technology, and the claimed invention corresponds to the eligibility criterion of "inventive step".

The claimed invention is industrially applicable and can be used for the manufacture of mortar used for waterproofing coatings with a restoring and protective effect.

Concrete example

1. Preparation of complex additives:

- dose:

- 20% sol solution of silicic acid with a pH of 4;

- potassium sulfate;

- a copolymer of Neolith acrylates in accordance with GOST 24211-91,

- metered components are manually transported to the mixer and mixed thoroughly until a homogeneous mixture of complex additives.

2. Preparation of mortar:

- dose:

- Portland cement (ПЦ400Д20);

- alumina cement;

- sand for construction work fraction 0.63 mm;

- dolomitic limestone with a fraction size of 100 microns;

- bentonite clay in accordance with GOST 28177-89;

- complex supplement;

- water

- metered components are transported to a horizontal batch screw mixer and mixed thoroughly until a homogeneous mortar mixture is obtained;

- the resulting mortar mixture is used for the manufacture of a waterproofing coating;

- an assessment of the adhesive strength at the age of 28 days of a waterproofing coating to a concrete base of class B15 and B22.5 as the most common concrete in construction is carried out using an attorney device Constant-A and using a ring with a diameter of 3 cm. Assessment of the change in the strength of the concrete base was made 28 days after applying a waterproofing coating and storing the sample under normal conditions.

The results of physical and mechanical tests of the adhesive strength of the waterproofing coating and the strength of the concrete base are presented in the table.

The results show that the specified component composition provides a mortar for a waterproofing coating with a 3.4-fold increased adhesive strength, and the use of a waterproofing coating provides an increase in the strength of the concrete base by 23%.

Claims (1)

Mortar, including Portland cement, alumina cement, sand for construction fraction 0.63 mm, dolomitic limestone fraction 100 microns, additive, water, characterized in that it additionally contains bentonite clay, and as an additive - a copolymer of Neolith acrylates, potassium sulfate and A 20% solution of silicic acid sol with a pH of 4, in the following ratio of the components of the additive, wt.%:
Neolith Acrylate Copolymer 23.5-25.5 potassium sulfate 36.0-37.5 the specified solution of silica sol 38.5-39.0
and the following ratio of solution components, wt.%:
Portland cement 25-27 alumina cement 8.1-8.3 specified limestone 7.9-8.3 specified sand 36.0-36.5 bentonite clay 0.7-0.8 specified complex additive 4.1-4.5; water 16.2-16.6