Treatment of concrete with a non-shrinking mixture. The best mixture for concrete repair. The material can be divided into two groups

Concrete is strong and durable. However, under the influence of various unfavorable factors, concrete begins to deteriorate: poor-quality pouring, non-compliance with the proportions of components, exposure to aggressive environments and mechanical damage.

A special tool can eliminate surface damage. concrete repair mixture, which, according to world and domestic experience, is much more effective than traditional cement-sand mortars. All repair mixtures for concrete existing in nature are divided into types:

• For repair of load-bearing structures (concrete columns, load-bearing beams, floor slabs and other structures);
• For repair asphalt concrete pavement and self-leveling floors;
• To protect concrete from corrosion.

In addition, repair mixtures are divided into casting mixtures (for horizontal surfaces) and thixotropic, for vertical and ceiling surfaces.

Factors influencing the choice of type of repair composition

• Type of damage: crack, chip, leveling or pothole of concrete;
• Size of damage;
• Terms of Use.

In this regard, there are the following types repair and concrete work:

• Strengthening the strength of the concrete surface;
• Surface leveling;
• Sealing cracks and potholes.

To strengthen concrete that carries significant loads and at the same time has a loose surface (concrete floor screed, floor slabs, etc.), as a rule, deep penetration primers are used.

The most common type of surface repair is concrete leveling and crack filling. Vertical cracks are sealed with thixotropic mixtures. They “adhere” perfectly to the surface, do not spread, have minimal shrinkage and have high strength, frost resistance and water resistance.

Particularly critical areas require the addition of reinforced fiber fiber, and prompt repairs are provided with special compounds. Horizontal damage can be repaired using injection molded repair compounds. These are more liquid substances, therefore they have minimal shrinkage, set faster and form a more durable “crust”.

Below are the best imported and domestic mixtures for repairing concrete surfaces depending on the type of repair.

• The best mixtures for leveling horizontal surfaces: “VOLMA-Nivelir Express”, “Vetonit-2000”, KESTONIT 97;
• Repairing chips and potholes: IVSIL EXPRESS-BASIS, Thomsit RS 88, “LAKHTA” quick repair»;
• Repair of cracking: “LAKHTA basic repair mixture”, BASF MasterEmaco S 488, Sika Monotop 612.

Remember! A correctly selected composition for concrete repair is the key and guarantee of the required long-lasting result.

Potholes, chips, cracks - all this can happen to any concrete surface. In this article we will tell you how and with what mixtures you can repair concrete.

Types of repair compounds

Concrete is known for its strength, reliability and durability. However, under the influence various factors over time it begins to deteriorate. The reason for this may be poor-quality installation, non-compliance with the proportions of the components, aggressive external environment, mechanical damage. Defects can be eliminated using special repair compounds.

In order to prepare the composition, you need to mix the dry repair mixture with water. It is possible to use special additives, which improve some characteristics of concrete. Ready-made formulations used for repairing floors, walls, stairs, bridges, roads and other concrete structures.

All repair mixtures can be divided according to their purpose:

• for repairing load-bearing concrete structures, for example, columns, beams, floor slabs;
• for repairing roads and concrete floors;
• to protect concrete structures from corrosion.

The market offers a fairly wide range of repair compounds with different properties, from different domestic and global manufacturers. Accordingly, their quality and price category can differ quite significantly.

Repair compositions must ensure high adhesion to concrete, non-shrinkage and absolute compatibility with it. With their help, the load-bearing capacity of structures is restored, water resistance, frost resistance and strength of concrete are increased. In addition, they must be accessible and economically feasible.

According to international and domestic experience, it has been proven that the use of repair mixtures is more effective than the use of traditional cement-sand mortars.

Repair mixtures for concrete are divided into thixotropic and castable. The first ones are used for vertical surfaces, the second ones for horizontal ones. The reinforcing properties can be increased using fiberglass.

How to choose a repair compound

Several factors influence the choice of repair composition:

• type of damage
• defect size
• terms of Use

There are three main types repair work:

• strengthening the concrete surface
• leveling the concrete surface
• crack repair

To strengthen concrete that carries heavy loads and has a fragile surface (screed, floor slabs), deep penetration primers are usually used.

The most common type of concrete repair is leveling out uneven surfaces. Sealing of vertical surfaces is carried out using thixotropic dry mixtures. They cling perfectly to the surface, stick well to them and do not blur. They have minimal shrinkage and high performance in strength, water and frost resistance.

Particularly critical areas require the addition of reinforced fiber fiber. Quick repairs are ensured by special compounds. Their hardening time is up to 6 hours. But they have a limitation on layer thickness - up to 30-40 mm.

Horizontal surfaces are leveled with casting mixtures. They are more liquid and, thanks to this, they are simply poured onto the surface. The mixture sets quickly, has minimal shrinkage and is quite durable. One layer can be laid up to 10 cm thick.

Leveling mixtures are also used to repair cracks in concrete.

The choice of repair composition is influenced by the operating conditions of the structure. If necessary, you can add components to the mixture that enhance different properties, for example, water resistance or fast drying.

The most famous manufacturers repair mixtures - BASF, MAPEI, SIKA, from Russian ones - Lakhta, Alit, Consolit, SpetsRemSmes.

Leveling the floor

To level the floor, you need to prepare a cement-sand screed. The concrete surface is first cleaned of dust and treated with a primer. After this, they determine the point at which the floor will be leveled, according to laser level beacons are installed.

Next, the screed is poured. Its maximum height should not exceed 35-40 mm. The pre-mixed solution is poured onto the surface and leveled with a spatula. On the second day, the beacons are removed and the seams are sealed with a trowel.

The screed should dry well. This may take up to 2 weeks. The screed is covered with film, and the surface itself is periodically moistened with water. Thanks to this, it will become stronger and will not crack.

Horizontal surfaces can be repaired using a self-leveling compound. They are used in the presence of small defects and uneven areas. The result of use is a perfectly flat surface.

To level the floor I use the following mixtures: “VOLMA-Nivelir Express” (cost: 14 rubles/kg), “Vetonit-2000” (17 rubles/kg), KESTONIT 97 (39 rubles/kg).

Repairing potholes on the floor

At the beginning of the work, small cuts are made around the damage using a diamond disc or grinder. Then the remnants of damaged concrete are removed with a chisel and a hammer drill, and the surface is cleaned of dust. For better adhesion of the composition to the concrete, a special epoxy primer is applied to the surface.

After applying the solution, it is necessary to remove its excess and use a lath to level the surface. After complete drying, the composition becomes as durable as possible. The sealed area is sanded.

The following mixtures are suitable for filling potholes: IVSIL EXPRESS-BASIS (cost - 10 rubles/kg), Thomsit RS 88 (30 rubles/kg), "LAKHTA quick repair" (80 rubles/kg).

Crack repair

Due to various reasons, cracks appear in concrete. Over time, they can increase, destroying the entire structure. This defect must be repaired.

Vertical cracks are repaired by injection. When using the injection method, the composition is pumped into the crack using special equipment - a packer.

Surface cracks, which usually form on inclined and horizontal surfaces, are repaired using the saturation method. In this case, the cracks are impregnated with the mixture without pressure.

There is another method for eliminating cracks. At the beginning of work, the crack is sawed 25-50 mm deep and 10-20 mm wide. Excess concrete must be removed and the crack must be blown out of dust and dirt. The cut is filled with repair mixture. If the concrete crumbles, it is worth using a higher quality mixture; if it produces virtually no dust, a cheaper product will do.

To repair cracks, you can use the following mixtures: “LAKHTA basic repair composition” (cost - 57 rubles / kg), BASF MasterEmaco S 488 (33 rubles / kg), Sika Monotop 612 (86 rubles / kg).

Comparative table of technical characteristics of dry repair mixtures:

The main technical characteristics presented in this table will help you choose the best option repair mixture for your needs.

The right mixture for concrete repair and quality work guarantee an excellent final result.

Andrey Badovsky, rmnt.ru

Exposed concrete is subject to permanent exposure to snow, rain, and sun. From season to season, structures experience temperature changes, the magnitude of which can reach 100°C. It's sad, but statistics demonstrate a very extensive experience of the fragility of the protection used.

Literally a year later, the seams and layers crack, leaks occur, and fluid accumulates in protective layer. During the next freeze/thaw cycle, peeling of the finish coating may occur. Therefore, the most serious requirements are imposed on the complex of repair and restoration work.

Long periods of downtime during concreting can cause poor setting of new and old concrete.

Designs made on the basis artificial stone, are destroyed under the influence of the following factors:

• chemical reactions– arise due to an increase in the level of carbon in artificial stone. They cause a violation of the w/c ratio in the solution;
• chemical reactions that occur under the influence of chlorine ions. Chlorine is found in road salt, which affects reinforced concrete road surfaces. The structure begins to oxidize the reinforcement;
• moisture- liquid can seep into the pores of concrete. At sub-zero temperatures it crystallizes, which causes concrete destruction and cracking;
• mechanical loads– dynamic influences and impacts exceeding permissible loads work to destroy concrete;
• natural disasters, seismic activity, fires;
• poses a serious risk non-compliance with technological standards at the construction stage. Here we can talk about the formation of cold seams, which during operation damages the strength and aesthetics of the structure.

Goals and methods of repairing concrete on the street

Repeated repairs carried out without following technology and using poorly selected materials can lead to further degradation of the structure, loss of bearing capacity and significant financial costs.

Restoration of concrete structures must be properly planned taking into account the following goals:

• restoration of the bearing capacity of the structure;
• protection of fittings from corrosion;
• strengthening concrete using composite materials.

The stages of repair work can be summarized as follows:

• inspection of the concrete structure;
• identifying the causes that led to destruction;
• planning of repair activities;
• selection of compositions and technologies;
• implementation of repairs;
• care;
• quality control.

Materials for repairing concrete floors

Objects can be industrial street sites, beams, floors, car roads and other coatings subject to strong dynamic loads

When choosing a material, the degree and nature of damage, the technical characteristics of concrete, and the specific operating conditions are always taken into account. It is necessary to monitor the compatibility of the repair composition and concrete, the degree of responsibility of the structure, the depth of destruction, the position and accessibility of the surface to be repaired.

Depending on the nature of the damage and the purpose of repair, the following types of mixtures are used:

• repair compounds used to restore the load-bearing capacity of concrete structures;
• compositions for non-structural restoration. In this case, minor defects are repaired and the surface is leveled.

In addition, it is customary to highlight:

• compositions for anti-corrosion protection fittings;
• materials for repair of unreinforced and reinforced concrete;
• waterproofing compounds;
• leveling mixtures;
• epoxy resins for repairing cracks using the injection method;
• finishing protective and decorative coatings.

Thixotropic mixtures (materials for structural repairs)

These are dry mixtures intended for the restoration of concrete and reinforced concrete structures on the street. The material is reinforced with polymer fiber and is characterized by compensated shrinkage. We can talk about a high degree of adhesion, water resistance, frost resistance, and mechanical strength.

Thixotropic mixtures are applied manually or mechanically, in a layer of 10-35 mm. Thanks to thixotropic characteristics, the working the solution works on vertical and horizontal bases, without requiring the use of stationary formwork.

Scope of application: mixtures are most often used for structural repairs (restoring load-bearing capacity) of vertical and horizontal foundations, for smoothing open reinforcing bars, filling traces of formwork, and repairing upper layers.

Flowable solutions

Scope of application: structural restoration of reinforced concrete columns, viaduct steps, floor slabs and beams, industrial floors, roads, filling gaps and cracks between slabs

These are dry mixtures used to repair concrete using the method of pouring into formwork. This option is indispensable where, due to the specificity and depth of the damage, high fluidity of the solution is required. The material is used when restoring road surfaces, when filling areas between concrete structures, etc.

The thickness of the application layer is 10-40 mm. When mixed with water, a solution is formed that is resistant to abrasion, delamination, and low temperatures. Plus, waterproofing properties are realized.

Typical technical parameters

Solutions for repairing concrete damaged by reinforcement corrosion

Such compositions are characterized by average strength and controlled shrinkage. They are used to repair concrete damaged due to corrosion processes in reinforcement. Layer thickness 5-35 mm. The use of formwork is not required.

Solutions of this type can be applied to vertical surfaces. In order for all the properties of the material to work fully on open concrete areas, it is recommended to use additional additives. The material is not suitable for structural repairs.

Scope of application: restoration of concrete destroyed by corrosion of reinforcement, balconies, beams, pillars, leveling defects on vertical surfaces, in technological, rigid joints.

Typical Specifications

Compounds with rapid strength development

The size of the aggregate in gravy mixtures can vary from 3 to 10 mm

These dry mixtures not only quickly gain strength, but are also designed to eliminate serious defects. This is a good solution for foundations under heavy loads, where long downtime is not possible ( industrial facilities, roads, runways, bridges). Some varieties can be used at sub-zero temperatures. Layer thickness 20-300 mm.

This group includes gravy mixtures - they do not shrink and are characterized by rapid hardening. The material is necessary for high-precision cementation and installation of equipment, including outdoors.

Scope of application: repair of road and airfield surfaces where urgent work is required, repair of concrete industrial sites, filling of hard joints, installation of fences, concrete pillars.

Typical technical parameters

Anchor mixtures

We are talking about a fluid, expanding concrete mixture that quickly gains strength and is not subject to shrinkage. Used for anchoring industrial equipment and fixing bases, filling technological cavities and seams.

Typical technical parameters

Injection solutions

To repair cracks, cement binder can be used, on the basis of which an injection solution is prepared.

The injection material is suitable for filling hard joints, cavities, cracks, compacting foundations, strengthening structures

Typical technical parameters

Waterproofing materials

Compositions of this type are used for waterproofing and secondary protection of concrete structures.

The material can be divided into two groups:

• elastic compounds for protection against atmospheric exposure and water load. These are ready-to-use two-component mixtures based on a special cement binder, synthetic polymers, and additives. After curing, a waterproof, elastic layer with high adhesion is formed. Optimal thickness application 2 mm;
• rigid waterproofing to protect structures in negative and positive conditions water pressure. These are ready-to-use one-component solutions based on cement binder, fine sand, and additives. After mixing, a plastic solution is formed. When cured, it forms a hard, waterproof layer with high adhesion. The optimal application thickness is 2-4 mm.

Typical Specifications:

The hard waterproofing layer can withstand pressure up to 1 atm

Equipment, tools and fixtures

Professional equipment and tools are required at every stage of repair and restoration work.

A typical set that should be on site:

• equipment for preliminary preparation of the base: sandblasting or shot-blasting installations and devices are used outdoors high pressure(hydraulic installations), compressed air compressors. Connecting the equipment may require mobile power stations required power. To repair defects and cracks, perforators and jackhammers are used, and the reinforcement is treated with metal brushes;
• equipment and tools for applying solutions: Manual application may require spatulas, brushes, and trowels. For mechanized application, shotcrete installations are used;
• equipment and tools for preparing solutions: concrete mixers are put to work. You may also need a construction drill with a mixing attachment, a shovel, clean containers, a measuring tool, instruments for determining the viscosity of the solution and searching for reinforcement;
• personal protective equipment, workwear.

Preparing the base

The edges of defects and recesses are produced with diamond discs, operating the tool perpendicular to the surface. Work to a depth of at least 10 mm. Using a needle gun or light hammer drill, concrete is removed from the defect.

The walls of the treatment area must be vertical, the base itself rough and even. If the surface is smooth, create a roughness with indentations of at least 5 mm.

Concrete must be cleaned of cement laitance, paint, grease, and oils. For final cleaning of the surface, compressed air from a compressor or high-pressure apparatus is used.

Surface cleaning can be carried out in several ways, depending on its actual condition and working conditions:

• hydraulic method– the technology does not work in cases where it is necessary to prevent an increase in air humidity. Otherwise, this is a universal and effective method used on almost any concrete;
• thermal– burners are used when the concrete is heavily contaminated with petroleum products, rubber, and oils. The method is effective for small depths of damage (up to 5 mm). Heating of the base should not exceed 90 degrees;
• mechanical- one of universal methods preparation. Concrete is cleaned using sandblasting equipment, hammer drills, and jackhammers, but mechanical processing is excluded where high dust levels should be avoided;
• chemical– an alternative to mechanical processing. The work area is treated with special compounds, after which it is washed with water.

Don’t forget about cleaning the fittings from rust. To do this, use a metal brush to work manually or use a mechanized method (sandblasting).

When the steel is completely exposed, the gap between the surface and the rods should be at least 20 mm

If a thixotropic compound is applied, the prepared concrete must be wet. Excess liquid is removed with compressed air or a sponge. It is necessary to achieve good moisture, but the base should not be wet.

Preparation of solutions

The technology of work depends on the type of mixture used. Of primary importance is the amount of mixing water and the mixing sequence.

Preparation of thixotropic solutions:

• To properly mix the working mixture, use the material in a whole container. The package is opened immediately before mixing;
• A precisely measured amount of water is poured into the concrete mixer (3.75 l for manual application, 3.9 for mechanical application);
• the mixer turns on, after which the dry mixture is continuously introduced into it. The kneading lasts 1-2 minutes;
• the equipment stops for a minute, the walls are cleaned of adhering dry mixture;
• if required, water is introduced, not more than 200 ml;
• then kneading continues for 2-3 minutes until a solution with a homogeneous consistency is produced;
• If it is impossible to provide proper moisture care for concrete, it is recommended to introduce moisture-retaining additives. The quantity is taken as 0.25 kg for every 100 kg of dry mixture;
• if you need to prepare a small amount of solution, it is permissible to mix it using a construction drill with a paddle attachment. Thixotropic mixtures are not mixed manually.

Preparation of flowable cement mortars:

• the working composition is prepared in a concrete mixer. The required amount of water is poured into the equipment bowl. To ensure medium fluidity, you will need 3.6-3.7 liters of liquid per 25 kg of dry powder; for high fluidity, take 3.8-4.0 liters per 25 kg;
• After adding water, the mixer starts, and dry powder is continuously introduced. The kneading lasts 1-2 minutes;
• the finished mixture should be liquid, without lumps;
• It is permissible to use an electric drill with an attachment. The composition is mixed manually in exceptional cases, prepared in small portions for 5-6 minutes.

Dry mixtures for repairing concrete damaged by corrosion of reinforcement, compositions with rapid strength gain are prepared in an identical way

Preparation of injection solution:

• 6-6.4 liters of water are poured into the concrete mixer and 20 kg of dry mixture is introduced. The solution is stirred for several minutes until a homogeneous fluid mass without lumps is formed.

Preparation of elastic waterproofing:

• liquid component B is poured into a clean container;
• Component A is slowly poured in and the mixture is kneaded with a low-speed construction mixer;
• the kneading lasts several minutes. Monitor the thoroughness of mixing at the bottom and walls of the container;
• waterproofing can be prepared in a concrete mixer equipped with mortar sprayers. With this method, you need to make sure that the mixture is homogeneous and without lumps. So it will calmly pour into the sediment funnel.

If it is necessary to prepare rigid waterproofing, add water to a clean container and add the dry mixture in portions. The composition is mixed with a low-speed mixer for 2-3 minutes. The material must stand for 10 minutes, after which it is remixed and put to work.

Application of solutions

Repair of concrete structures can be carried out using special equipment or hand tools.

Application of thixotropic solution:

• thixotropic mixtures are applied to vertical or horizontal structures manually using a trowel or spatula. You can use a mechanized method using special equipment (shotcrete installations);
• the permissible thickness of one layer is taken as 35 mm. The layer-by-layer exposure time should be 4 hours;
• before applying the material, the reinforcement must be cleaned and coated with an anti-corrosion compound;
• the temperature of the base during repairs should not be lower than +5 degrees. When it rains and strong wind the composition is not applied;
• average consumption – 19 kg of dry powder per m2 of surface when producing a layer of 1 cm;
• The repaired area is moistened within 24 hours.

Application of flowable solution:

• the prepared solution is continuously poured into the formwork, the concrete is pre-impregnated with water. Before starting work, the formwork is treated with appropriate materials (lubricants) to prevent the absorption of water contained in the solution;
• during the pouring process do not use vibrating slats, vibrators, etc.;
• the material must fill the entire volume of the formwork. If there are hard-to-reach places, the solution is applied there manually;
• in hot weather, they are used to prepare the mixture cold water, the filling is protected from solar radiation. Average consumption – 20 kg/m2 per 1 cm layer.

Application of solutions with rapid strength gain:

• the prepared material is poured onto the prepared surface without the use of vibration;
• the composition is evenly distributed over the entire area of ​​the repaired area using a trowel, spatula, or trowel. Smoothing is carried out immediately after leveling.

The internal parts of the formwork are treated with lubricant for subsequent easy dismantling

If the solution is poured into the formwork, it is continuously fed from the selected side (there should be only one). This will help prevent air from becoming trapped. The surface requires care within 24 hours.

Application of injection solution:

• Ensure that the substrate is structurally resistant to injection pressure. Otherwise, it is necessary to strengthen the concrete;
• the solution is injected under a pressure of 1-2 atm, through pre-installed packers (tubes);
• work begins with the lower packer, gradually moving upward until all defects are filled. Typical consumption is 1.6 kg to fill a 1 liter cavity.

Application of elastic waterproofing:

• after preparation, the solution must be applied within 1 hour;
• if implied manual application, the material is spread with a smooth spatula. The second layer is applied on top of the fresh first layer. The thickness of the two-layer system should not be higher than 2 mm;
• for large volumes of work, the composition is applied by spraying;
• if it is necessary to waterproof critical structures (intensive loads), a fiberglass reinforcing mesh is pressed into the fresh layer. After this, the surface is leveled and after 4-5 hours the second layer is applied.

Rigid waterproofing is applied by spraying, brush or spatula. If a brush is used, 2-3 layers are applied, observing layer-by-layer drying (5-6 hours). When using a spatula, it is still recommended to apply the first layer with a brush.

When spraying, waterproofing is applied in two layers, after waiting for the first to partially harden.. The final coating thickness should be 2-3 mm. In windy and hot weather, the base is protected from rapid evaporation of moisture with polyethylene film.

Protection of fittings from corrosion

Reinforcement bars must be cleaned of traces of corrosion. During the work, the possibility of applying an anti-corrosion composition to back side fittings. When preparing the working solution, the amount of water used is controlled. The thickness of the applied layer is measured with a caliper (before and after application).

When the reinforcement is processed, a solution with anti-corrosion properties is applied. Application to vertical surfaces is realized manually using a spatula or trowel. Maximum thickness layer – 35 mm. Mechanized technology using special equipment is acceptable. The exposure time for each layer is 4 hours.

Repair of concrete floor screed

Thixotropic solutions are successfully used to restore such bases. With their help you can eliminate minor defects, large cracks, carry out major renovation. The principles of surface preparation and solution preparation remain typical. Before sealing defects or pouring a new screed with a thixotropic mixture, priming is carried out.

Quality control

After completion of repair and restoration work, quality control is carried out, for which special equipment and visual inspection are used. Most often, structures are checked using mechanical methods: adhesion meters, sclerometers, hammers, instruments that determine the quality of the floor screed.

After measurements, the obtained characteristics are compared with regulatory documents

Safety precautions when repairing concrete on the street

Persons of adult age (18+) are allowed to carry out work. All workers must undergo appropriate instruction, medical examination and training. Provision of personal protective equipment is required. Repair compounds may cause irritation upon contact with skin and mucous membranes. If such contact occurs, the affected area is cleaned with plenty of water and medical attention is sought.

Cost of work

Average financial costs for restoration of structures for various purposes start from 2.5 tr. behind cubic meter. This price includes preliminary preparation of the base, the main stage of work and maintenance.

conclusions

The choice of material for repairing artificial stone should have A complex approach. The application of a particular technology depends on performance characteristics foundations, the condition of the concrete, the degree of its damage.

Modern cement mixtures, with which the market is so filled, are considered a universal solution to the issue of repair and restoration concrete structures. Thixotropic compounds have successfully proven themselves in restoring the load-bearing capacity of even the most critical objects.

Flowable, anchoring and quick-hardening mortars are used in any repair practice for leveling and sealing damage to concrete that is not subject to high loads.

An example of repairing concrete structures on the street is shown in the video:

Repair mixtures for concrete are used when we need to eliminate damage to the surface without dismantling and re-filling. Of course, the strength of the structure may decrease somewhat, but still the final condition will be much better than before the repair.

Below we will tell you what mixtures can be used to seal cracks and cracks, how to prepare such products yourself, and what to pay attention to when using them.

Even a heavily damaged surface can be restored using high-quality materials

General questions about the repair of concrete structuresThe most common damage

Concrete is a fairly durable material, and it is for this reason that it is widely used in construction. However, such surfaces are also subject to wear, so sooner or later they require restoration.

Photo of the damaged surface

As a rule, in everyday life we ​​encounter either damage to concrete load-bearing structures (foundations, plinths, walls) or defects in the floor screed.

The most common problems include:

• Dusting - finely dispersed destruction of the surface layer. It occurs as a result of a violation of the filling technology, as well as with a significant intensity of operational loads. Eliminated by applying film-forming compounds - sealings.
• Cracks - formed when heavy loads are applied to a small area, as well as due to temperature deformations. In addition, concrete can crack during shrinkage.

Advice!
To avoid the appearance of deformation and shrinkage cracks, it is necessary to take measures at the stage of preparing the structure for pouring concrete.
For this, various damper tapes, expansion joints, etc. are used.

• Footprints mechanical damage- chips, potholes, holes etc. This also includes traces from structural elements - mortgages, beacons, formwork parts.
• Level differences caused by uneven shrinkage of the base.

And if in the latter case it is necessary to carry out a large-scale restoration of almost the entire floor, then if cracks or potholes appear, the concrete repair mixture will help restore the surface.

Concrete floor prepared for renovation

Types of mixtures

A variety of compounds are used to carry out repair work. Their range is very extensive, but still it can be divided into two groups. The easiest way to analyze the characteristics of materials is by studying the table below:

As for the material, non-shrink cement is widely used for the manufacture of such compositions, as well as polymers - epoxy resin and polyurethane. All products in this category are characterized by fairly rapid hardening, which is why they are used for express restoration - when there is no time to wait for the concrete structure to fully gain strength.

Application of bulk mixture

An additional advantage may be the presence of fiber in the repair mixture - steel or polymer fibers. When the product hardens, concrete fiber strengthens the edges of the damaged base, significantly increasing its strength. True, the price of such reinforcing agents will be slightly higher.

Self-production

If you don’t want to spend money on buying branded material, then you can easily make a mixture for repairing concrete surfaces with your own hands. Of course, its effectiveness will be somewhat lower, but for household needs she'll do just fine.

You can also prepare the product yourself

To prepare we will need:

• PVA glue or bustylate, diluted with water in a ratio of 1:3.
• Cement – ​​1 part.
• Sand sifted through a fine sieve - 3 parts.

The material is prepared immediately before the start of repairs.

For this:

• Let's fall asleep cement-sand mixture into a container with a wide neck.
• Add adhesive suspension to the dry material, gradually mixing the solution by hand. It is important not to overdo it with water - the composition should be quite dense.
• When all the material is in the container, take a drill with a mixer attachment and mix the composition until completely homogeneous. As a rule, three to five minutes are enough for this.

Method for eliminating damagePreparing the base

Crack bridging scheme

Usually, any mixture for repairing concrete surfaces is accompanied by instructions that clearly regulate the process of its use.

• First, we need to inspect the damaged area and roughly estimate the amount of material we will need.
• Then we remove concrete fragments, dust, debris, etc. from the crack. For small defects, you can use a stiff brush, but for significant damage, it is more convenient to clean with sandblasting or high-pressure water jetting.
• To secure the edges, the crack can be deepened 20-50 mm below the line of natural destruction. In the process of bridging cracks, cutting reinforced concrete with diamond wheels is often used, which makes it possible to obtain perfectly smooth edges and eliminate all weakly adherent areas.

In some cases, diamond drilling into concrete is used to remove damaged parts.

Advice!
On longitudinal cracks, experts recommend cutting transverse grooves in increments of about 20 cm for more effective fastening.

• Particular attention should be paid to the reinforcement frame. All metal parts, protruding beyond the concrete surface, we clean it to a shine. Then we apply an anti-corrosion primer to the stripped rods to prevent oxidation of the material during the hydration of the repair mixture.
• If the depth of the defect exceeds 50 mm, then additional reinforcement must be placed into it. The reinforcement is installed in such a way that the metal is subsequently covered with a layer of mortar no thinner than 20 mm.

After completing all this work, we re-dust the area. Then we moisten all surfaces, trying, however, to prevent the accumulation of large drops.

Preparation and application of the composition

The mixture for repairing concrete surfaces, prepared independently, can be applied immediately. And here are the compositions industrial production need to be properly diluted with water.

Only in this case will the material acquire the characteristics necessary for effective joint filling and polymerization:

• As a rule, both flowable and thixotropic mixtures require a relatively small volume of liquid. On average, 120 to 250 ml of water is consumed per 1 kg of dry material.
• Pour cool water in a minimum volume (exact numbers are indicated in the instructions) into a container or concrete mixer. Then add the dry component, gradually mixing the material.

Note!
Manual processing does not provide the desired homogeneity of the product, so you must use an electric mixer.
For small volumes, it is possible to use a drill with a special attachment.

We apply casting agents in this way:

• We install formwork along the perimeter of the restored area. It is advisable that its height be at least 50 mm greater than the planned coverage level.
• Pour the prepared fluid mixture onto the concrete, evenly distributing it from one edge to the other. This sequence of actions will avoid trapping air bubbles.
• Vibratory compaction of the composition is not required in most cases. To remove air pockets at the junction of the surface and the formwork, it is enough to run a metal strip around the perimeter.

We act differently with thixotropic agents:

• We collect a small amount of material on a spatula or grater.

Filling the defect with a thixotropic non-shrinking solution

• We forcefully press the compound into the crack, filling it by 15-25 mm in one pass.
• After waiting some time for the layer to polymerize, we repeat the treatment until the defect is eliminated.
• Smooth the surface with a moistened steel float, trying to mask all protrusions and irregularities. Repeated leveling using the same tool is carried out after the mixture has set, i.e. at least half an hour after application.

To prevent the repair composition from cracking, it must be kept moist for 24 hours, and in hot weather - up to three days or more. To do this, periodically spray the restored area with water from a spray bottle or hose, and then cover it with polyethylene or burlap.

Grouting the surface

Advice!
It is advisable that during the entire drying period there are no drafts or drafts in the room. sharp changes temperature.

When used optimally, concrete repair mixtures will help restore the surface of almost any structure. Compliance with the rules for preparing the solution and its application makes it possible to preserve mechanical properties surfaces, and in some cases, seriously improve them. The video in this article will help to understand the nuances of the technology for those who plan to do such repairs themselves.

Concrete is a material used in all areas of construction, the main advantages of which are high strength, reliability and durability. But over time, even concrete structures collapse. There can be several reasons for the appearance of cracks, chips, and deformations: violation of the ratio of elements during mixing, mechanical stress, environmental influences, loads, etc. Special mixtures are used to restore the material.

Repair mixtures are used for quick restoration various concrete structures, restoration of their geometric parameters and operational characteristics.

There are two types of repair compounds for concrete:

• injection molding;
• dry.

Casting mixtures for concrete are used to fill pre-prepared cracks and recesses. They have the ability to expand and a high degree of adhesion to concrete, stone and reinforcement, and when hardened they practically do not shrink. Filling it all out free space, the solution reliably seals and strengthens the surface being repaired. Casting mixtures are used for the restoration of horizontal surfaces.

Concrete restoration and strengthening monolithic structures also carried out using dry compounds. The high level of frost resistance and strength allows the use of dry mixtures for the repair of products subjected to negative impact natural phenomena and cyclic loads. Thanks to good characteristics and the moisture resistance of the substance that has gained strength, it is often used to waterproof concrete. The material is completely non-toxic, so it is used, for example, to repair drinking water tanks.

Dry formulations are used:

• for restoration of load-bearing surfaces, floors, stairs;
• for road restoration;
• to protect concrete from corrosion.

The listed types are presented on domestic market in a wide range. The cost depends on their quality, characteristics and manufacturer.

Review of popular manufacturers

The requirements for cast and dry mixtures are as follows:

• high degree of adhesion with the restored surface (concrete, stone, reinforcement);
• eliminating shrinkage.

Often the main aspect influencing the buyer's choice is the price of the product. Especially if you need to purchase a large batch for concrete repair.

Accept correct solution will help short review popular brands.

"Emaco"

The Russian company Basf manufactures and sells Emako compounds used to repair concrete damage of varying degrees of complexity: from small cracks to complex deformations.

• "Emako" N 5100 is used for the first degree of damage: the presence of dirt, cracks, cavities.
• Using Emako N 900, N 5200, damage of the second degree is repaired: crumbled or peeled areas of the surface, as well as small chips.
• Emaco S 488 PG, S 488, S 5400 cope perfectly with rust and cracks up to 0.2 mm and a depth of no more than 40 mm (third degree).
• Cracks larger than 0.2 mm, exposed reinforcement, high level of carbonization - fourth degree, depth up to 100 mm - are restored with Emako compounds T1100 TIX, S 466, S560FR.
• Heavily damaged concrete structures with exposed reinforcement and chips more than 200 mm deep are restored using non-shrink (“Emako” A 640) and anti-corrosion (“Emako Nanocrete AP”) mixtures.

You can buy Basf on the company’s official website. The cost varies from 850 to 1,700 rubles per 25 kg package, depending on the components of the composition.

"Birss"

The Birss mixture for restoring concrete foundations is produced in Russia and is intended for repairs of any degree of complexity.

• Birss 28, 29, 30, 30N - simple repair of cracks and peeling surfaces.
• Birss 30 C1, 58 C1, 59 C2 (restoring) are used for the second degree of concrete wear.
• For the third degree of damage, Birss 59S3, 59 Ts compositions are used.
• To correct larger defects, the following Birss mixtures are used: Concrete putty, RBM or 600 VRS (non-shrinkable).
• With the help of Birss RSM, complex damage to concrete structures is restored.

The frost resistance of Birss compounds allows repairs to be carried out at sub-zero temperatures. They have high adhesive strength, elasticity, density and water resistance.

The advantage of the material is its affordable cost: from 400 to 450 rubles per 50 kg.

Another representative domestic production- repair mixture " Bars Consolidation", which is excellent for the restoration of vertical and horizontal structures. “Bars” gains the required strength as quickly as possible and does not shrink. The mixture has high level adhesion to concrete.

There are liquid and thixtotropic compositions. The first ones differ in the thickness of the applied layer, the slope of the surface being repaired and the cost. Price liquid mixtures varies from 800 to 1,000 rubles per 30 kg.

Thixtotropic solutions "Consolit Bars" are:

• reinforcing (113 B60);
• finishing (115 B50);
• repair non-shrink (111 B30).

The moisture-resistant coating is created by the “Consolit Bars 100” mixture, which has an expansion function.

The price varies from 900 to 1,500 rubles per 30 kg, depending on the components of the composition and the region of sales.

"Ceresit CX5"

Repair of concrete structures in conditions high humidity It is better to do this using the Ceresit mixture (“Ceresit CX5”), which does not shrink when hardened and forms a moisture-resistant and frost-resistant coating that reliably covers all defects.

Ceresit, which has high technical characteristics, is quite expensive - about 2,700 rubles per 25 kg.

"Knauf"

Waterproofing of concrete is usually carried out using the Knauf Flachendicht mixture, which, in addition to leveling the surface, makes it moisture-resistant and vapor-tight. The advantage of the composition is the absence of toxic additives and convenient packaging of 5-6 kg. The Knauf solution can be used both outside and indoors. Price – from 350 rubles per 5 kg.

"Osnovit"

New on Russian market– “Osnovit Innoline NC60” from “INDASTRO”. This is a gravy composition used for repairing vertical and horizontal surfaces. The mixture is used not only for restoration work, but also for installing equipment on a concrete base. The mixture costs about 800 rubles per 25 kg.

Using the dry leveler Osnovit Selform T-112, concrete floors and walls are repaired different types. Has a high level of adhesion and water-repellent properties. Costs from 160 rubles for 20 kg.

"Alit"

The composition of dry mixes "Alit" (SDR-UR, SDR-U, SDR-UM) includes quartz sand fine fraction, hydraulic binders and non-toxic polymer additives. The composition smooths out large cracks and chips, with a depth of 2 to 20 mm, formed on concrete bases, load-bearing structures, stairs.

Possessing resistance to negative temperatures, Alit allows repairs to be carried out in winter.

The price of the mixture is from 1,100 rubles per 25 kg.

Mapei
Quick and convenient concrete repairs are guaranteed by the producers of Mapei dry mixes. The solutions do not shrink when hardened, do not crack, and eliminate cavitation, erosion and abrasion. Mapei repair compounds are presented on the Russian market in a large assortment:

High-strength material is used to restore floors in industrial workshops, repair airfield slabs, roads, canals and tunnels.

The cost of the mixtures depends on the components included in the composition and varies from 850 to 1,300 rubles per 25 kg.

"SW"

"SW" is a dry mixture used for repairing reinforced concrete products. The advantages of "SW" are resistance to the effects of adverse external factors: mechanical and dynamic loads, high and low temperatures. The moisture-resistant and durable composition is suitable for performing repair work as quickly as possible. short time. When the solution hardens, it forms an anti-corrosion protective covering and is an excellent waterproofing agent.

Price for 25 kg – from 240 to 260 rubles.

How to choose the right repair material

To choose the right mixture for concrete repair, you must follow a certain algorithm of actions.

• Determine the parameters of the repaired area: type of surface, amount of damage, load during operation.
• Select the type of mixture: cast or dry.
• Select the type of solution (with good adhesion, fiber reinforced).
• Compare prices, mixture components and choose a manufacturer.
• Calculate the amount of material required to complete the work.

Before ordering and purchasing the mixture, you need to pay attention to the following characteristics:

• hardening time;
• mixture consumption per 1 m2;
• protective functions of the solution;
• shrinkage (shrink-free compounds should be selected).

The market offers a huge number of different repair compounds for restoring concrete structures that have lost their original characteristics. They differ in composition, functionality, consumption, price, and quantity per package.

The correct choice of repair mixture guarantees concrete structures many more years of safe service.

Cost of mixtures for concrete repair

Approximate prices for restoration compositions are shown in the table below.