How to strengthen the old foundation of the house. Strengthening the foundation: when to do it and what methods are used to strengthen the foundation of the house

The basis of each house, whether it is a multi-storey building or a private one-story house, begins with the construction of a foundation. In the future, this part of the structure will bear the main load, the foundation is subject to erosion from rains and melting snow, severe frosts also affect its strength, and of course, over the years, the foundation wears out and collapses. This is especially noticeable if the house is old. In order for the building to stand for many more years, it is necessary to take some actions, strengthen and restore the foundation. Of course, it is usually necessary to strengthen the foundation of an old house, and in relatively new buildings this is no exception. For a long time, these actions have been based on increasing the footprint of the house, but over time, much has changed, and now new, better building materials have become available, as well as new ways to strengthen.

Reasons for the destruction of the foundation

1. Mistakes in the design of the building - it is extremely important to take into account all the nuances even at the time of designing the future home. You need to understand what area the building will occupy and think over the design of the foundation so that the weight of the building is distributed very evenly. If these calculations were not correct, the foundation would collapse and deform.
2. Non-compliance with construction technologies - the foundation of the house, which is made of cement mortar, will it be based on piles or solid ground? If the solution is kneaded in the wrong proportions, the result will be disappointing in the future.
3. Soil features - the soil is different, it may be too damp or loose. Groundwater can flow too close to the surface, all of these factors greatly affect the integrity of the foundation.
4. Excavation works near the house - in such works, for example, laying pipes, and not following basic precautions, the foundation can be damaged by the workers themselves, who, for example, did not dig the trench deep enough.
5. The susceptibility of a building to vibrations, vibrations, or shaking of the ground.

Foundation wear assessment

It is very important to be able to assess the condition of the foundation. The first visible signals that indicate the destruction of the foundation of the house are cracks. When they appear, it is necessary to stick the so-called “beacon” on the crack, they can serve as strips of masking tape. If after a while this strip remains intact, it means that the foundation of the house has stabilized and it is enough just to make a small concrete screed. If the strip of adhesive tape is torn, then the foundation continues to collapse, and it is urgent to take appropriate action.

A huge role in strengthening the foundation of the house is played by what materials your house is built from. The complexity and specificity of the work will directly depend on this.

Methods for strengthening the base of the house

Nowadays, a lot of tricks and methods are used to strengthen the worn-out foundation of the house, among them there are new and old ones, but the plus of the old ones is that they are time-tested. And their implementation does not require any technical or professional knowledge. As with everything these days, these methods are more expensive and cheaper, so you can choose the method that suits you best.

Before starting work, you need to take into account the fact that the material from which your house is built also affects the complexity of future work, so strengthening the foundation of a brick house is fundamentally different from working with a wooden base. For example, strengthening the foundation of a wooden house requires first raising the entire building into the air; for this, it is customary to use special jacks. Thus, it becomes possible not only to restore the foundation of the house, but also to completely replace it with a new one! For a brick house, this method is simply impossible.

Next, you need to know that the methods of restoring the foundation are also different, here are the most common of them:

• Tape
• pile
• The method of "reinforced concrete shirt"
• Broadening method

Let's consider each of these methods separately.

strip foundation method

This type of foundation is used at the base of the house in eight out of ten cases. It can be deep or shallow, and is presented in the form of a concrete structure, which is laid around the perimeter of the future building. Also in the strip foundation, in those places where the load-bearing walls will be located, special partitions can be provided. This decision is made to enhance the reliability of the building and to achieve a more even distribution of the load on the ground. However, the strip foundation is subject to swelling and subsidence of the soil, from which the building may tilt towards the subsidence of the soil.

It is customary to strengthen the strip foundation by building a new one on it, this method is perfect if the question is how to strengthen the foundation of an old house. To do this, a moat 30-50 cm wide and about a meter deep is dug around the perimeter of the building.

Now that the moat is dug, you need to clean the old base from dirt and plaster as well as possible. Then, holes are drilled in the old base for the reinforcement bars, they will serve as an adhesive base for the new screed.

Having prepared the reinforcement, making a kind of mesh out of it, a formwork is built along the entire ditch, where the cement mortar is then poured. Thus, the mortar will fill the entire space between the old foundation of the house and the formwork, and the reinforcement mesh will serve as a binding material. The formwork can only be removed after a fairly long time, the solution must completely harden.

pile method

Strengthening the foundation with piles is used on soft and loose types of soil, when another foundation will simply collapse due to the characteristics of the soil. To date, there are three ways to strengthen the support of the house with piles:

Reinforced concrete jacket method

It is best to resort to this method when strengthening the foundation of a brick house, since it involves strengthening not only the foundation of the house, but also a fragment of the wall. But before strengthening the foundation with a “reinforced concrete jacket”, you need to carefully clean the old base and make special notches on it, on which reinforcement is eventually installed, poured with concrete.

To further strengthen the structure, anchors can be placed in the base of the wall, they will add rigidity to this type of foundation. With this "Makar" it is extremely successful to strengthen the columns of the house and the popliteal areas.

Warp broadening method

This method is very common, but takes a lot of time, and also requires you to know the exact sequence of actions. The first step will be marking the entire perimeter of the building on the grip, the length of each marking is approximately 2-3 meters. Further, having marked the entire perimeter, they begin to tear off the base, the main thing is to do this consistently. Then a trench is dug around the building, the bottom of which is completely covered with rubble, a thin layer, about 3-5 centimeters.

After that, you need to drill holes in the base into which reinforcement or metal pins will be inserted. Beams are mounted between the wall and the base of the house, onto which a long metal bar is welded in the next step. The final of all these actions will be the already familiar installation of formwork and pouring concrete.

Foundation below freezing depth

This foundation of the house is practically not subject to freezing and all kinds of soil influences, due to the fact that it is very deep, i.e. below the freezing depth of the soil. But here another problem arises - groundwater.

Under the ground, there is a constant erosion of the base of the foundation and, starting to fight this, you must first do drainage procedures. Then all the destroyed concrete is removed and restoration work begins immediately.

Strengthening the foundation of an old house in this way is carried out in the same way as in the case of a tape version. But at the end of the work, it is necessary to take care of installing additional waterproofing in order to protect the building from further erosion by groundwater.

The foundation is the foundation of any building. The longevity of the building depends on its reliability and quality. An erroneous choice of the type of foundation, miscalculations during its laying cause defects over time, which sooner or later will lead to the destruction of the entire structure. Therefore, at the first signs of deformation, it is necessary to immediately establish the causes of its occurrence and proceed to eliminate them in order to avoid a costly complete replacement of the foundation.

Signs and causes of partial destruction of the base

Strengthening the foundation should be carried out in two cases: when signs of structural deformation are found and when it is planned to complete the floors. Before starting work, you need to carefully analyze the condition of the house, assess the degree of destruction of the foundation or the likelihood of defects in the near future, and only after that proceed with strengthening work.

Most often, professionals with special equipment are invited to identify flaws. But you can do the work yourself if you correctly evaluate all the factors and follow the step-by-step instructions for strengthening the foundation. Only one thing cannot be done when defects are found - to ignore them, so that subsequently the inevitable replacement of the foundation does not result in a round sum.

It is possible to identify the initial stages of destruction by several obvious or hidden signs. Obvious signs can be seen with the naked eye, these include:

• the appearance of deformations on the surface of the floor;
• change in the level of the soil and the formation of dips around the base;
• defects on the exterior of the house or its destruction;
• small cracks on the walls and plinth;
• local small damage in the building itself and in the adjacent area.

Barely noticeable cracks have already appeared on the basement of this house. If urgent measures are not taken, then all this beauty, unfortunately, will be destroyed.

With hidden defects, it is more difficult; special equipment is required here. However, if at least something worries you, for example, part of the decorative plaster on the facade or plinth has peeled off, or the soil around the house has slightly subsided, do not take the time and money for specialists.

Thus, you will save yourself from more serious problems. Experts will quickly find out the cause and suggest how to eliminate it. And if you wish, you will do the work yourself.

The destruction of the foundation of the house occurs for many reasons. The main ones are:

In addition, the influence of the environment affects: small underground fluctuations, sharp warming, temperature changes, prolonged rains and an abundance of snow, as a result of which the level of groundwater rises and the processes of heaving of the soil begin.

Under the influence of frost heaving, cracks appear on the walls of the house. This indicates the beginning of the deformation of the foundation

Of course, it is impossible to foresee all the detrimental consequences of natural disasters, but it is necessary to calculate the risks even at the stage of designing a house.

Preparatory work before strengthening the foundation

Preparation for strengthening the foundation is divided into 2 stages - examination of the foundation and its unloading.

Foundation survey

The revision of the foundation of the building can be planned (periodic inspection, so as not to miss the beginning of the destruction) and unscheduled. The latter is carried out:

The study is carried out in different ways, depending on the approach to the constituent elements of the structure and the magnitude of the destruction. The easiest way is to conduct a visual inspection with fixing the detected flaws in a photo or video in order to observe the defects.

An external check is done in easily accessible, well-observed places without any tools. They mainly inspect the pits, the upper surface of the base, its base and grillage. Pay attention to the corrosion of concrete, the reinforcement exposed due to chips, the destruction of the masonry, the appearance of gaps, rust and cracks, the violation of the integrity of the monolith.

A visual inspection is usually carried out during the day, but it does not give such clear results as an instrumental examination using special equipment.

Instrumental control is necessary in the following cases:

• when the area of ​​deformation of all sections in total exceeds 10%;
• in case of violation of the spatial arrangement of the structure (this may be a slope, shift or draft);
• if the depth of the chips reaches 1.5 cm.

Before strengthening the reinforced concrete foundation, it is first determined whether its shrinkage has stopped - beacons are installed across the cracks and observed for a month. If no changes are found, start the strengthening work.

Foundation unloading

This is the final, but very important stage of the preparatory work, since it allows you to prevent distortions when strengthening the foundation. Yes, and interfering with the structural basis of any structure, without redistributing the load in whole or in part on temporary structural supports, is fraught with destruction of it as a whole.

Partial unloading (redistribution) is carried out using transient supports made of wood, as well as metal or wooden struts. In the underground room or on the lower floor of the house, at a distance of about 2 m from the wall partitions, support pillows are laid, and on top of them - a beam with racks. The top run is attached to the posts with anchors (as shown in the figure). After that, wedges are driven in between the supporting lower beam and the uprights, transferring the load from the ceilings to the transient supports.

Scheme of partial unloading of the foundation using temporary wooden supports: 1 - foundation, 2 - walls, 3 - ceilings, 4 - upper run, 5 - stand, 6 - wedges, 7 - support beam, 8 - support pad

Complete unloading of the base is done using foundation beams (they are called rand beams) or transverse and longitudinal beams made of reinforced concrete or metal:

Ways to strengthen foundations

After a survey of the ground structures of the building and the foundation itself, establishing the causes of destruction and partial or complete unloading of the base, work on strengthening can begin.

This is a lightweight and convenient technology that is suitable for strengthening shallow foundations. She can do it on her own.

Reinforcing the foundation with a reinforced concrete clip is a simple and affordable technology that can be used to easily repair a deformed foundation on your own.

For work, concrete grade 400, reinforcement Ø 16–18 mm, wire, anchors and injection tubes (if their use is provided) are needed.

It turns out a reinforced concrete belt (clip), which rigidly fixes the foundation and prevents its further deformation. If the bearing capacity of the original base is insufficient, the clip is made with a broadening in the lower part.

For rubble bases with a large number of voids, injection tubes are used, installed in the foundation so that they extend 35–40 cm beyond the walls of the cage. Through them, a cement mortar is injected into the foundation cavity after the casing has completely solidified. The solution fills the voids and sets with the surface of the foundation, and the clip forms an additional contour that ensures the integrity and strength of the base. After two or three days, the injection tubes are cut off.

Strengthening of foundations with a large number of voids is carried out using a concrete clip and injection tubes

Strengthening the foundation with a reinforced concrete jacket

Strengthening the base with a shirt is done in a similar way. The difference is only in the amount of coverage - the clip fits the entire perimeter of the foundation, and the reinforcement with a shirt is done only on damaged surfaces.

Reinforced concrete jacket reinforcement technology has proven itself for the reconstruction and repair of strip and column foundations

This strengthening method well strengthens columnar and strip foundations.

Strengthening the foundation with ebbs

This technique is used to strengthen brick and rubble bases. Its principle is as follows: instead of the reinforcing core, reinforced concrete ebbs are used:

Strengthening the foundation by widening the sole

The sole is a supporting reinforced concrete structure for the base. It can be widened by laying slabs or by installing a reinforced concrete cushion. The technology of widening the sole in both cases is quite complicated, but with the help of a few people you can cope with this task without involving professionals.

Strengthening with shotcrete is an ideal option for repairing the foundation of a brick house. It is very difficult to perform such work on your own, it is better to entrust it to specialists.

Scheme of strengthening the foundation with shotcrete: 1 - reinforced foundation, 2 - reinforced brick wall, 3 - reinforced concrete clip, 4 - anchors, 5 - basement ceiling, 6 - basement floor mark, 7 - zone of compressed base soil

If you are confident in your abilities, then you will need:

• perforator;
• shotcrete gun;
• gravel, sand and cement;
• shovel.

Strengthening the foundation takes place in 2 stages: first, work is done on one side of the base and only after a week they move to the opposite side. Such a time interval allows you to maximize the strength of the structure. The gripping areas must be at least 2.5 m in length.

Reinforcement with shotcrete is considered one of the best reinforcement schemes, since it significantly increases not only the bearing capacity of the foundation, but also its water resistance.

Strengthening the foundation of the house with grouting

Cementation (injection) - filling of base cavities, voids and cracks along the entire length. It is made both to strengthen the foundation of the house, and to prevent excess moisture from seeping deep into the structure.

Strengthening is carried out manually or using a special injection pump.

An interval of two to three days should be maintained between the construction of the cage and the filling of the pre-inserted tubes. It makes sense to carry out cementation if the foundation of the building has not lost its bearing capacity.

It is also possible to restore the bearing capacity of the foundation by filling cracks, voids and seams using modern mixtures and resins, for example, MC-Injekt 2700 (injection resin) and a pump.

Strengthening the foundation with piles

Today, in areas with heterogeneous soil, the method of strengthening the foundation with screw piles is popular. It is good because the piles used, thanks to the unique design of the blades, can withstand loads of up to 25 tons. However, this method of amplification is very expensive, it requires special equipment and the participation of professional builders.

Video: strengthening the foundation - twisting screw piles

Micropiles Ø 150–300 mm

A good way to strengthen is convenient, uncomplicated and affordable. Allows you to combine drilling with injection. The hoses used in this case remain inside the pile, which ensures reliability and high quality reinforcement.

Driven piles

They are used to strengthen the foundation of buildings on solid ground. To perform the work will require special equipment. To ensure better docking of the foundation with piles, beams are mounted in the base.

External piles

This method of strengthening is used in areas with a high level of groundwater. The base is taken out on piles, having previously passed a reinforced concrete beam through it, which will hold the structure.

To strengthen the foundation, an iron beam is passed through it and then external piles are brought under it.

Bored piles

At an angle to the old base, deep pits are drilled, reinforced and poured with concrete.

1. Places of fortification are chosen and internal and external wells with a diameter of 170–240 mm are drilled at an inclination of 45 ° to a depth of solid ground.
2. A reinforcing frame made in advance is lowered into them and a concrete mixture is poured under high pressure. After hardening, the entire structure is attached to the base with anchors.

Strengthening the foundation with bored piles is easy to do with your own hands if you have the appropriate equipment.

The advantages of this technique:

• all load-bearing elements are strengthened: foundation, interfloor and attic floors, blind area, walls, basement;
• no need for a large amount of earthwork;
• suitable for any type of buildings;
• good results in a relatively short time;
• together with reinforcement, waterproofing of the base is additionally provided;
• this scheme is effective on the most difficult soils.

The main disadvantage of the described scheme is the need to use special equipment. Therefore, despite the fact that the process itself is not very complicated, this technique is used quite rarely.

Strip foundation reinforcement technology

The reinforcement of the strip foundation is carried out in sections, preventing the entire foundation from being excavated at once. You can speed up the work if you carry out them from different sides at the same time.

If you do repairs yourself, then you can do without piles. After cleaning the old foundation, a reinforcing structure is created in the trench. Make a formwork and fill it with concrete.

Video: strengthening the strip foundation

New high-tech ways to strengthen the foundation

One of the new methods of strengthening is the DEEP INJECTION technique (deep injection), which helps to restore and strengthen the bearing capacity of the foundation. It requires a large amount of earthworks and the use of heavy construction equipment.

Using the DEEP INJECTION technology, the geopolymer composition is injected directly under the base of the foundation

The method is based on the point introduction of a two-component polymer resin into the earth's thickness. Thanks to the action of the polymer, voids are filled, moisture is displaced from the pores, the base of the house is compacted and rises to its previous level. At the same time, the bearing capacity of all structural elements increases.

If the house was built on a weak site and has already begun to sag, then it's time to try another know-how - POWERPILE technology, which strengthens the soil and restores the bearing properties of the foundation.

At a depth of 6 m, injection pipes in a Kevlavr sheath are brought into the ground and, under pressure, they are filled with a geopolymer composition that expands and hardens. A kind of polymer pile is formed. It equally well counteracts shear and breaking loads, therefore, it significantly increases the strength of the base.

The SLAB LIFTING technology also deserves attention, which will stop the subsidence of the concrete floor slab, raise the structure to the mark provided for by the project, and increase the bearing capacity of the foundation.

Video: do-it-yourself foundation repair

Of course, it is impossible to describe all the technologies for strengthening foundations. Each technique is developed individually, taking into account the results of surveys and design indicators. Owners of private housing construction need to remember that do-it-yourself strengthening work can be carried out only after a thorough inspection, obtaining the results of examinations and relevant conclusions.

Many residents of private homes sooner or later face such a problem as. This is due to shrinkage of the house, fatigue of materials. If the foundation has served for more than 10-15 years and has already exhausted its resources, then it's time to update and strengthen it on your own. It is very good if you built the basis of the house with your own hands and know how everything was done, what frame structures are inside and what materials were used.

You can strengthen the old foundation by making a reinforcing cage, which is installed at the corners, and even better around the entire perimeter, and poured with concrete.

Having noticed that the window openings are warped, and deep cracks have gone in the base of the house, you need to start strengthening the fundamental part of the building. To do this, you can invite specialists, or you can tackle the problem yourself. You should first analyze the state of the foundation of your house in order to understand which of the ways to strengthen the base will be the most effective and optimal in your particular situation.

Causes of the destruction of the foundation of the building

Virtually anything can cause the foundation of a house to collapse, from damage to materials to the presence of a building in close proximity to your home. Here are the main prerequisites that can take place:

Scheme of destruction of the foundation: (forces: a - gravity, b - soil resistance, c - frost heaving): 1. Subsidence of the soil; 2. Pushing out the foundation; 3. Frosty swelling; 4. Overturning of the foundation.

1. Failure to comply with the technology of the process of building a house during its construction, as well as the use of low-quality materials, which leads to rapid wear of the foundation.
2. The construction of the house took place without taking into account the characteristics and composition of the soil, which led to the wrong selection of construction technology and the choice of the wrong materials.
3. Possible errors in the calculation of the load on the foundation during its laying.
4. A change in the level of groundwater, namely an increase, including abundant soil moisture (for example, a spring flood).
5. The heterogeneous composition of the soil, the movement of the soil can also lead to the need to strengthen the foundation.
6. Carrying out land or construction work in the immediate vicinity of the house, for example, laying pipes, building another house.
7. Possible freezing of clay soil, which is very common if the foundation was laid with errors, according to a technology that was never followed.
8. A thorough redevelopment of the house, which involves the displacement or transfer (destruction) of the bearing walls.

Before that, it is necessary to understand the reasons for its shrinkage and be sure to eliminate them. If you do not do this, then the same thing can happen with the new base as with the old one.

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Where do you need to start?

It is better to start by determining how you are going to strengthen the foundation of your house. There are three main methods for strengthening the foundation:

1. Classic way.
2. Reinforced concrete shirt.
3. Piling method.

All of them are often used in construction work, each has its pros and cons, as well as "indications". You should choose one or another method based on your own preferences, financial capabilities. First, collect all the tools and materials that you may need to strengthen the foundation. Here is a list of such tools:

1. Bulgarian.
2. Welding machine.
3. Roulette construction.
4. Special wire cutters.
5. Construction hammer.
6. Reinforcing cages or twigs.
7. Piles to strengthen the foundation.
8. Concrete mix.
9. Rubble.
10. construction gloves.
11. Shovel.
12. Wooden beams.
13. waterproofing material.

Having prepared everything you need, you can get down to business. Next, all three ways of how to strengthen the foundation will be considered in order to understand the features of each of them.

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Strengthening by the classical method

This is one of the most economical methods that has already been tested for centuries, and therefore you can be 100% sure that such a foundation will last for many more years. To implement this type of work, you will not need new materials and technological tools, it will be enough that you have already provided and prepared. The essence of the work is to create a new one around, thereby strengthening it and making it more durable and protected. To begin with, it follows from all corners of the house to give them rigidity. The new layer of the foundation of the house must have a width of at least 1 m, and go half a meter lower in depth than the old layer.

Now you can, armed with the necessary tools, make a reinforcing cage for corner joints. After their manufacture, lower them into prepared pits and fill them with high-quality and durable concrete. At this stage, saving on cement mortar is not worth it, because it should serve you for many years. Work must be carried out very quickly so that bare areas do not remain so for too long. If the work will be carried out around the entire perimeter of the house, then each section must be done in stages. Until one segment dries, it is not recommended to proceed to the next.

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Reinforced concrete shirt as a way to strengthen the foundation

This type of work assumes that not only the old foundation will be strengthened, but also the walls of your house. To do this, special anchors are built into the walls and foundation, into which concrete is poured. Before strengthening the foundation, it is necessary to waterproof the prepared foundation with the help of special tools. The next step is the arrangement of a brick wall, which is the most reliable material in this situation. Strengthening the foundation in this way is the best way to secure your home.

Along with this, the method of broadening the foundation is also used, which involves adding it from all sides. First you need to measure and mark everything on the grip, after which you can alternately tear off the old foundation through the grip itself. The surface must be cleaned of construction and other debris, after which, at the place where the old foundation is located, or rather around it, dig a trench and fill it with rubble. Now you can drill holes in the base into which the metal pins will be installed. The next step is to install the beams between the brick wall and the base.

This way to strengthen the foundation of the house should bring very good results. Even significant damage to the foundation can be corrected by strengthening the base in this way. After carrying out all the above works, it is necessary to install the formwork in the trench and pour it with concrete. This way you will get a fully reinforced foundation of your house, even affecting the walls, which will provide even more protection from destruction.

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Strengthening the house with piles

Another method that simply cannot be passed by, because it is used in cases where the foundation is very badly destroyed and its strengthening is an urgent need.

If there are problems with the soil, for example, its shrinkage or an increase in the level of groundwater, then it is best to strengthen the base of the building by installing special piles.

The work is quite difficult, requiring attention, but the results are very good. Piles can be installed along the perimeter of the old foundation, or under it. Here it is necessary to find an individual solution by studying different ways to strengthen the basis of the house.

There are several ways to strengthen houses with piles:

1. The bored method, the essence of which is to punch wells around the entire perimeter of the building inside and out. They are stuffed with rebar and filled with concrete. The depth of each well must be at least two meters, and the distance between them must be maintained at 1.5 m. These piles are attached to the house with reliable anchor bolts.
2. The indentation method, it is used in cases where the houses are already quite old and it is impossible to apply excessive physical force and pressure to them. In this case, the piles are not driven into the foundation, but are slowly and gradually pressed into place. This is done with the help of special equipment, since it is simply impossible to carry out this type of work on your own.
3. screw method. This is the most common method that is used when you need to strengthen the foundation, it is the most effective. In order to install the piles, you will need outside help, as a couple of working hands are not enough.

There are some nuances that you need to familiarize yourself with before you decide to strengthen the basis of a private house in this way:

1. First you need to carefully study the old foundation, since the choice of one or another method of installing piles depends on its condition. If the base is very old and can collapse at any time, then it is better to choose the method.
2. Many are interested in whether it is possible to perform such work on their own, the answer is obvious: in most cases, you will need special equipment that was created specifically for such purposes. Of course, you can do all the accompanying work yourself.
3. Most often, screw piles are used to strengthen the foundation of houses. This is a convenient and effective method that requires the participation of special equipment and tools.
4. If you need to strengthen the foundation of the tape type, then it is better to start by balancing the impact of underground forces. This is done by increasing the area of ​​​​the base of the house.

Often, buildings that have been in operation for a long time need repair. This applies not only to the roof and walls of the structure. The base structure requires special attention, since it is on it that the main load from the building falls. The expiration of the service life of the base, seasonal heaving of the soil, excessive moisture - these factors can lead to the destruction of the entire house. To avoid trouble, you should strengthen the foundation. There are many reinforcement methods, each of which is calculated for a specific type of structure. You can do the work yourself, but some technologies require the presence of heavy equipment.

Sources of destruction of the basis and methods of its strengthening

If the owner of a private country house noticed that cracks appeared on the basis of the building, or the base began to crumble, he should urgently do repairs. Cracking and crumbling is a characteristic behavior for bases that require immediate restoration. If you ignore the current situation, the foundation will undergo even more serious deformation up to complete destruction.

The foundation of a newly erected building can also sink if building codes were not observed during its laying. Most often, the bases of new buildings are destroyed if:

• Mistakes were made in the design of the base;
• The master deviated from the technology of the device;
• All necessary surveys have not been carried out on the site.

To secure the basis of the future home, it is worth remembering that before starting work on the device, you need to determine:

• The level of seismic activity of the earth in the region in which the site is located;
• Qualitative characteristics of the soil in the building area;
• Level of groundwater flow;
• ground freezing level.

Do not despair if for some reason the base has become unusable, because it is almost always possible to reanimate the base of the building. If the owner decides to strengthen the foundation of a private house, he should pay attention to certain rules that must be followed regardless of the chosen restoration technology:

• The perimeter of the building is conditionally divided into parts (length - from 2 m to 3 m). Strengthening is carried out gradually - first in one area, then in the next;
• It is forbidden to start strengthening the opposite part of the foundation if the foundation is not fully mature. This process takes about seven days.

As for the strengthening methods themselves, the most popular among them are:

• Classical;
• shotcrete;
• Reinforced concrete shirt;
• Strengthening by means of piles.

Reinforcement of the base by shotcrete

If the basic structure of the building was made of brick, it can be repaired using shotcrete. The work is carried out using shotcrete. The strengthened basis will become especially resistant and durable. In addition, when strengthening the base of the building with shotcrete, the structure will acquire a new quality - water resistance, therefore, the owner of the house will not have to perform additional waterproofing.

However, in order to strengthen the foundations of buildings in this way, it is necessary to hire special construction equipment. This entails additional financial costs.

Shotcrete technology consists in the fact that a protective solution is applied under pressure to the front and rear verticals and horizontals of the basis. Work to strengthen the weakened surface of the base of brick blocks is carried out in several steps:

• A trench is dug along the boundaries of the building. Its width should be 1-2 m;
• The base is cleaned of contaminants, it is also necessary to get rid of the remnants of the unusable solution;
• Notches are made on the masonry plane (depth - 1-1.5 cm) to increase the adhesion force of concrete to the base surface;
• Formwork is made from sheets of plywood or wooden panels. The finished frame is installed in the trench;
• Using a special concrete gun under pressure, a solution is applied.

In order to save money, the cementing method is often used: small holes are drilled in the foundation and under the building, after which they are filled with a not too thick cement mixture. The base will become monolithic, which will increase its bearing capacity and increase the durability of the supporting structure.

Budget option for strengthening the base

It happens that the owner of the site does not have the opportunity to hire professional contractors or rent special equipment. Therefore, it is not surprising that every second developer practices strengthening the foundation of a private house with his own hands.

There is a classic technology for strengthening the foundation of a structure, which has been used for over a hundred years. This method is suitable for bases made of blocks. The purpose of the classical method is to build a new foundation for the finished building.

The work begins with strengthening the main load-bearing elements of the building - its corners. Initially, a trench is dug along the corners of the building, which must open the base to a width of 100 cm. The depth of the trench should exceed the depth of the old foundation by 50 cm.

For corner supports, a frame is made of reinforcing bars (mesh size - 20 by 20 cm). It is not recommended to increase the cell size, as this action will adversely affect the stability of the finished base.

The resulting reinforcing skeleton is installed in the corner recesses, after which it is poured with a concrete mixture.

This strengthening can be carried out along the boundaries of the entire base, if necessary. Do not forget that it is worth doing the work in parts, filling small areas with concrete (up to 2 m). If you follow all the rules and recommendations, the old damaged base will find a new life.

The method of strengthening the tape base

The tape basis is the most popular basis erected under wooden and block structures. It is the tape that is arranged for most houses in private suburban areas. Reinforced concrete jacketing is the best solution in a situation where it is necessary to strengthen the strip foundation. This strengthening technique helps to protect not only the foundation itself, but also the walls of the building.

There is the possibility of making a reinforced concrete shirt with your own hands, since the execution technology is quite simple:

• Restoration work begins with digging a trench around the perimeter of the building. The minimum width of such a recess should be 1 m;
• The opened base is cleared of the remnants of the earth and crumbling concrete;
• The base is waterproofed with bituminous mastic;
• Notches are made to improve the adhesion of the foundation walls to the concrete mortar;
• Anchors are installed in the base;
• A brick wall is laid out along the boundaries of the structure. She will act as a formwork;
• The space between the masonry and the base is reinforced, the frame is connected to the anchors;
• Concrete solution is being poured.

The reinforced concrete shirt will mature within a week. Such strengthening will make the tape especially strong and stable.

Video reinforcement of the strip foundation:

Strengthening the foundation structure with piles

If there is a need to strengthen the foundation of a brick house, the most appropriate option would be the reconstruction method using piles.

Pile reinforcement is made from different types of elements. Based on the variant of the supports, the method of their installation is selected. Most often, masters opt for screw piles, as they can be installed independently. In addition, the deepening of the "screws" does not take much time. Such elements are metal pipes, pointed at the end. In their lower part there are special blades that simplify the device.

Also, to strengthen the base, bored supports are used. Their installation is somewhat more complicated, but such piles have a more significant bearing capacity.

To begin with, wells are drilled in the soil (on the sides of the building), into which supporting elements will be installed. The depth of the holes is determined by the qualities of the soil prevailing on the site. The diameter of the wells should not exceed 25 cm.

Casing pipes are installed in prepared wells, which are reinforced and poured with concrete. Ripe concrete is coated with bitumen and covered with roofing material.

If the foundation of the structure has fallen into disrepair, it is necessary to immediately take up its strengthening. It must be remembered that before you start strengthening the foundation of an old house, you should determine the exact cause of its damage. This will help to correctly select the method of restoration of the basis.

Video strengthening the foundation of a private house with your own hands:

Often, owners of private houses are faced with the problem of the destruction of the foundation. Most often this applies to old log or timber buildings. But sometimes strengthening is also required for the foundation of a new house, if the technology was not observed during the construction and natural factors were taken into account, for example, how deep the soil freezes in the territory. In some cases, the foundation is destroyed if any objects are built near the house. And, finally, the foundation needs to be strengthened if it is planned to add additional premises or add floors to an already finished building. If this is neglected, then an increase in the mass of the building can lead to subsidence, distortion of the entrance and window structures, the formation of cracks in the base, and even complete destruction.

Causes of partial destruction of the foundation

The foundation is the platform on which the structure is based. It distributes the mass of the building over the entire area and reduces the specific pressure on the soil. The performance and durability of the structure depend on its condition, since it is on the base that all the load from higher structures falls.

Deep cracks in the foundation indicate the beginning of destruction

But during the operation of the building, the foundation is often subjected to partial destruction. This may be due to the following reasons:

• the location of the house on sloping terrain, in a seismically unstable area or next to the railway;
• incorrectly drawn up project;
• errors at the stage of calculating the planned load;
• non-compliance with construction technologies during the construction of the platform;
• the use of low-quality building materials;
• improper arrangement of waterproofing;
• a decrease in the quality characteristics of the base;
• natural phenomena - flooding, oversaturation of the soil with moisture, freezing of the soil;
• human economic activity - improper operation of the house, for example, lack of seasonal heating, construction or laying of communications in the immediate vicinity of the foundation, repair or completion of the house.

Since at the initial stage of construction it is not always possible to accurately predict what kind of load and natural factors the foundation will be exposed to, subsequently it will be necessary to resort to strengthening it. Strengthening the foundation ensures the reliability and safety of the operation of a private house, since it is suburban households that are most exposed to natural factors. If you ignore the problem, you may have to completely change the foundation, and this costs a lot of money.

Before starting work on strengthening the foundation, it is necessary to conduct a thorough analysis of the reasons that caused its partial destruction. As a rule, professionals with special equipment are invited for this. They evaluate the factors that cause foundation deformation and make recommendations to eliminate or minimize them.

Preparing to strengthen the foundation

Before strengthening the foundation, its external and internal inspection is carried out. During the external examination, the following parameters are determined:

• building dimensions;
• condition of supporting structures;
• the presence of cracks and bevels.

During underground research, indicators are determined:

• device and dimensions of the platform;
• strength properties of the material used;
• the depth of its bookmark.

Before starting work on strengthening the foundation, it is necessary to make sure that its shrinkage is over. It usually lasts at least a month. To understand that the shrinkage is over, gypsum beacons are installed across the identified cracks. Their condition will allow you to determine when you can start strengthening the base.

At the final stage of preparation for strengthening, the platform is unloaded. It may be complete or partial. An important factor is the prevention of distortions that will adversely affect during the restoration of the foundation.

To further strengthen the foundation, the building is raised with jacks

Partial unloading of the platform of the house is carried out using wooden or metal supports and struts.

1. In the basement, install support pads, stepping back from the wall 2 m.
2. Place a support bar on top.
3. Fasten the stands.
4. Then connect them with a beam to the ceiling, and then to the support beam using wedges.

For capital unloading of the platform, steel strapping beams are mounted.

1. Under the row of masonry, in which the bricks are laid with short edges to the wall, punch the strobes on both sides, keeping a distance of 2 m between them.
2. Place the tie beams in them and secure with 25mm bolts.
3. Using overlays, weld the joints of the beams, and fill in the gaps from the wall to the beam with a sand-cement mortar.
4. Punch holes in the lower part of the walls, keeping the distance between them no more than 3 m, insert beams into the holes.
5. Install the crossbeams on the support pads on both sides of the wall.

Base strengthening methods

In modern construction, different methods of strengthening the foundation are used, due to the rapid development of the building materials market:

• widening of the sole;
• piles;
• reinforced concrete pillow;
• basement replacement;
• reinforcing belt;
• reinforced concrete shirt;
• cementation;
• ebbs;
• summing up new grounds;
• clips;
• shotcrete.

Various methods are used to strengthen the foundation.

Each of these methods has both advantages and disadvantages. Consider the most popular technologies.

Outsole widening

In practice, home owners most often resort to the classic, proven method of strengthening the foundation - the method of widening the sole. The sole is a reinforced concrete pillow on which the foundation rests. This method is the simplest, most reliable and relatively inexpensive. Several people with certain skills can handle the job.

1. An additional foundation is laid around the house, which plays the role of an auxiliary support.
2. The sole along the entire perimeter of the structure is fixed at several pre-marked base points, the number of which depends on the size of the building and the degree of destruction of the main foundation. Typically, the distance between the points is 2.5–3 m.
3. On the sides and under the foundation, excavation is carried out.
4. A reinforcing screed is laid under the foundation and evenly filled with mortar.
5. Air bubbles are removed using a concrete vibrator.
6. The side walls of the sole rise to the plinth by 15 cm.

The method of strengthening the foundation by widening the sole is the simplest, most reliable and relatively inexpensive.

Strengthening the foundation with piles

There are many types of piles with which you can strengthen the foundation.

Bored piles

Additional strength can be given to the structure with the help of bored injection piles. Recently, this technique has become very popular. But due to the use of innovative technologies, expensive materials, drilling equipment and the involvement of specialists, this method is considered quite expensive.

The essence of the technology is as follows:

After the solution dries, a new foundation of pile structures is formed, which, in terms of strength and reliability, resembles a monolith on which the structure is based.

Additional strength can be given to the structure with the help of bored injection piles.

Micropiles

In some cases, micropiles are used. Their diameter is 150–300 mm. In the process of drilling, it is possible to fill the wells with a solution. This method involves the use of drill rods. Remaining inside the pile, they provide more reliable reinforcement of the foundation.

With the help of micropiles, it is possible to strengthen not only the foundation, but also the soil

Video: strengthening the foundation with micropiles

Driven piles

Pressed piles are used to transfer the load to solid deep-seated soils. They are installed using special equipment. Beams mounted in the base provide a good connection between the foundation and piles.

Video: strengthening the foundation with pressed piles

The method of strengthening the foundation with remote piles is used at an elevated level of groundwater. The foundation is taken out on piles. The connecting link between the piles and the foundation is a reinforced concrete beam passed through the foundation.

The foundation is carried out on piles

Metal tubular piles

Installation of metal tubular piles is carried out on both sides of the platform. For this, a welding method using special equipment is used. To install the piles, a reinforced concrete frame is mounted and connected to the beams supported by jacks.

Metal piles are connected with a reinforced concrete beam

Pouring reinforced concrete pad

The advantages of strengthening the platform by pouring a reinforced concrete pad are:

• reduced pressure on the soil due to the large footprint;
• additional ground insulation. This prevents frost heave, which is considered the most common cause of foundation failure.

The disadvantages of the technology include the impossibility of pouring the entire foundation, but only in sections of no more than 2 m, and the need to observe the drying time of each section before pouring the next one. Therefore, this method is used to strengthen one of the corners of the base, or in the event that the time and cost of pouring the foundation around is not fundamental.

Reinforced concrete cushion reduces the load on the ground and allows you to insulate it

Filling the pillow under the foundation takes place in several stages:

1. The repaired area is dug around outside and inside the building. At the same time, the blind area and the floor are removed, the earth is dug around the base in the form of two trenches with a length of 3.0 m to 3.5 m and a depth of ¾ of the depth of the foundation.
2. The condition of the foundation is assessed for the presence of cracks and destroyed areas.
3. If the base is in order, a hole is dug under the pillow up to 2 m long and 0.4–0.5 m deep relative to the foundation. The bottom of the pit should be level.
4. Geotextiles are laid in the pit, sand is poured in a layer of 3-5 cm and a 10-cm layer of crushed stone with a fraction of 30-40 mm.
5. To level the surface, clean sand is poured over the rubble, and then a 5-centimeter layer of foam is placed.
6. The reinforcing structure is laid on top and the formwork is installed.
7. The base is poured with concrete and compacted with a vibrator.
8. The formwork is removed after 2 days.
9. You can start repairing the next section no earlier than after 25-28 days.

It is important that the concrete contains as little water as possible. The optimal proportion of water to concrete is 1:4. But too thick concrete is difficult to pour into a trench, so it can be diluted with a plasticizer sold in hardware stores.

The height of the finished reinforced concrete pad should be at least 10 cm of the repaired section of the foundation. This will strengthen the base and reduce the pressure on the ground.

In winter, it is not recommended to repair the foundation by pouring a concrete cushion. If dug trenches remain, protect them from frost heaving: cover with earth and cover with foam.

Video: strengthening the foundation by pouring a concrete pad

Plinth replacement

If shedding or destruction of the platform has occurred in the area of ​​\u200b\u200bthe base, this part must be replaced. It is easiest to replace under a wooden building, as it weighs less than stone or brick.

The easiest way to replace the plinth under a wooden building

Under a structure made of stone or brick, the plinth is changed in parts no longer than 1 m with intervals between sections of at least 3 m. To carry out the work, you will need:

• fittings;
• cement;
• sand;
• crushed stone;
• plasticizer;
• concrete mixer;
• chain saw for concrete for cutting the necessary sections of the base;
• perforator;
• welding machine for fastening reinforcing elements.

How to replace the base with your own hands

Video: replacing the basement with the rise of the house

Filling reinforcing belt

If the platform is covered with cracks, but their number does not increase over time, then the repair is carried out by pouring a reinforcing belt. This makes it possible to prevent further destruction of the base and protect it from deformation at low temperatures, but its strength does not increase significantly. The reinforcing belt is allowed to be poured both along the entire perimeter and along one wall.

1. First of all, the foundation is excavated outside the building. The outer part of the foundation should be completely free from the ground, but you should not dig deeper than a sand or gravel cushion. The optimal ditch width is 0.8–1.0 m.

   The outer part of the foundation must be completely free from the ground

2. Then it is necessary to compact the soil near the foundation by manual tamping and pour a layer of crushed stone with a fraction of 30–50 mm and a thickness of 10–15 cm. The crushed stone is also compacted. A thin layer of sand is poured over it to hide the sharp edges.
3. On top of the sand, a dense foam 5 cm thick should be laid and covered with a tarpaulin to protect the material from sparks during the welding process.
4. Further, in the foundation, it is necessary to drill holes with a diameter of 18–25 mm at a distance of 60–90 cm and drive pieces of reinforcement into them, which will serve as anchors. Trimmings should protrude from the wall by 15–30 cm.
5. Weld external and internal meshes made of reinforcement 10–14 mm thick to them, which should recede from the base by 5–7 cm. The meshes are connected to each other using pieces of reinforcement.

   Reinforcing meshes are connected with reinforcement

6. In the lower part of the belt, an additional reinforcing mesh is arranged for a pillow with a thickness of 25–35 cm, and equal in size to the width of the ditch. The pillow reduces the load on the ground without the need to dig the foundation.
7. After creating a reinforcing mesh, remove the tarpaulin from the foam and install the formwork. Concrete is poured in two stages. After pouring the pillow, you should wait 2 days, and then proceed to fill the belt.

   Concrete pouring is carried out in two stages

8. After 2 days, you can remove the formwork, and after another 3-5 days, fill the ditch with earth.

Pouring a reinforced concrete jacket

A common way to strengthen the foundation is to pour a reinforced concrete jacket.

The foundation for pouring a concrete jacket is dug out, taking into account the length of the tabs no more than 3 m

This method is quite simple. A person with the slightest skills in construction can pour a reinforced concrete shirt alone. This will require the following materials:

• concrete grade M400;
• fittings for tying the frame with a thickness of 16–18 mm.

Work order

cementation method

The method of cementation is also called injection. This is due to the introduction of hollow tubes into the platform cracks. As a rule, it is used to give strength to a rubble foundation that has many voids. Mortar is poured into them, and small cracks are covered up. This method is considered quite affordable, but it is used only for foundations with preserved bearing capacity.

The cementing composition is introduced using special injectors

Strengthening the base with ebbs

Sometimes the foundation is reinforced with ebbs. This technology is used to strengthen platforms made of brick or rubble. Reinforced concrete sills are used instead of the reinforcing cage.

The order of work is as follows:

1. Reinforced concrete sills are installed on both sides and squeezed out, while the lower part should touch the wall, and the upper one should not.
2. The structure is fixed with jacks and ties.
3. Then trenches are dug with a 2-meter grip.
4. The ditches between the wall and the resulting structure are filled with mortar.

Reinforced concrete sills are used instead of the reinforcing cage

This technology provides for increasing the strength of the platform with double-sided reinforced concrete clips or tubes through which the solution is injected. It fills all the voids of the masonry, due to this, the base is strengthened throughout the entire thickness.

1. At the initial stage, you need to dig out a part of the foundation to be repaired. Its length should be approximately 3 m, width - 1 m, depth - 0.5 m.
2. Then, on both sides, drill through holes in a checkerboard pattern and insert 20 mm reinforcement bars into them.
3. After that, it is necessary to attach a frame with cells measuring 150x150 mm to the reinforcement.
4. At the final stage, the formwork is installed and the resulting space is poured with concrete.

The method of reinforcement with clips allows you to strengthen the foundation throughout the thickness

Shotcrete reinforcement method

This technique is suitable for reinforcing a platform that is not too damaged or when planning to build additional floors. Reinforcement with shotcrete will reduce the pressure on the platform.

With this method, a concrete gun is used, so it is better to entrust the work to specialists. Strengthening the foundation is carried out in several stages.

Video: strengthening the foundation by shotcrete

Strengthening the strip foundation is carried out using a special technology and includes the following steps:

Video: strengthening the strip foundation

The most common cause of platform damage is ground heaving due to heavy rains, floods and freezing water. In this case, the building, as it were, is pushed out of the ground and warps. If the house is located in an area with close groundwater and an unstable climate, during construction it is necessary to think over the drainage system and arrange waterproofing of the foundation. The decision on how best to strengthen the foundation is made after studying the land and analyzing the damage.