How to strengthen the old strip foundation of a wooden house. Strengthening the foundation: when to do it and what methods are used to strengthen the foundation of a house. Strengthening the foundation by widening the sole

The owner of a private house always wonders how to strengthen the foundation. Should you entrust it to someone or try to do everything yourself? Let's look at the main stages and weigh the forces.

You will have to correct the negative consequences of external factors on the foundation under the house, but what to do if you have never had to do foundation repairs yourself in your life? To understand which strengthening of the foundation of a building is preferable, you should understand the reason for its collapse. There are two explanations why pieces of the foundation suddenly begin to fall off and the foundation itself crumble: technology violations during construction or external negative factors (soil displacement, changes in its composition, groundwater movement, vibration).

Collapse of the foundation of the building

The first reason may include improper preparation of the binder mortar, poor-quality building materials, incorrect measurements, which led to misalignment of the masonry. The second “critical point” may be that during construction the composition of the soil, its moisture content were not taken into account, or the drainage was carried out incorrectly.

To determine whether the destruction of the foundation under the house continues and whether its strengthening needs to be organized urgently, paper tapes should be glued to the detected cracks. If they are not torn apart within a week, then the splits will not expand. You can use plaster tapes. In addition to visual inspection, soil samples are taken, including to determine its chemical composition. Thanks to this analysis, it is possible to select building materials that are not affected by external factors or their harmful effects are minimal.

Prevention of foundation construction

Like any structure, the foundation needs mandatory preventive procedures. Thanks to them, you can significantly extend the life of a private home and delay strengthening and putting it in proper order. It is recommended to pay attention to the following “pain points”:

Before building a foundation, be sure to use geodetic and geological services, which will determine whether it is possible to build a residential building on a certain plot of land.
In no case do not deviate from the requirements of technology: do not use a binding solution that does not correspond to the design, bricks with other hygroscopic properties, and do not skimp on the components of the concrete mixture.
Do not make changes to the plan of a private house (reconstruction of load-bearing partitions and walls, construction of additional floors and extensions), which may change the application of support points to the foundation and redistribute the weight load of the main building.
You should not neglect the construction of a shock-absorbing cushion under the foundation, drainage ditches and moisture insulation. For long-term operation of the building, you should not skimp on this work.
All communications should be laid before the foundation is erected. The deployment of these measures after construction can lead to improper shrinkage of the entire building, and as a result, to the appearance of cracks and destruction of its foundation.

Let's start with the most popular, one might say, classic way of strengthening the foundation. The algorithm of actions has already been worked out for centuries, and therefore is most preferable because of its effectiveness and efficiency, and can be completely implemented with your own hands. The point is to build a new foundation, which is laid out around the house along its perimeter and serves as additional support for laying the old foundation. All work is divided into a number of successive stages.

First, square holes must be dug at each corner of the building in order to expose the masonry of the old foundation. The parameters of the pit are 1x1 m. The depth must be 0.5 m below the old base. Then you will need to make frames from reinforcement according to the number of corners of the building or along the length of the walls, if you decide to reinforce the entire perimeter. Then comes the installation of structures made of metal rods into the resulting recesses and the filling of square holes with reinforcement with concrete, the grade of which guarantees the special strength of the material.

Strengthening the foundation with a structure made of metal rods

The work is quite scrupulous - exposing the old foundation for too long can lead to negative effects of the external environment and subsequent distortion. That is why it is recommended to divide the pouring perimeter into sections not exceeding a length of 2 m. The next sector will be strengthened after the concrete in the previous one has “set” completely. For the same reason, it is recommended to expose the corner parts of the foundation as it is poured, so that the exposure time is minimal.

Strengthening the foundation of a wooden house

If the first method is quite possible to do with your own hands even alone, then for wooden house organizing strengthening of the foundation is a little more difficult. The fact is that the most common problem with such buildings is rotting of the crown, that is, decay of the lower logs of the log house. For everything to go well, it is necessary to replace this part of the hut; at the same time, you can use the opportunity to lay waterproofing material.

How to strengthen the foundation of a wooden private house with your own hands - step-by-step diagram

Step 1: Disassemble the base

It should be noted that the operation to replace the crown should precede the strengthening of the base. First, a small dismantling of the foundation is done under the lower log in order to freely remove the rotten wood. At the junctions with other logs it is necessary to make cuts.

Step 2: Update the entire perimeter

Afterwards, part of the dismantled foundation is restored. When the entire procedure is done, the same is done on the opposite side of the house. Having finished with one row around the perimeter, you can begin replacing the next one. It should be noted that the crown of a wooden house consists of two rows of logs, and when replaced, each one must be impregnated with special compounds and covered with a waterproofing agent.

Step 3: Unload the house

But what to do if not only the logs are let down, but also old foundation collapsed in several places and serious work is needed to restore it? Here you can’t do without hydraulic devices. Remove the load on the foundation, i.e. remove heavy furniture and equipment from the room. It is also advisable to dismantle the doors and floor.

Step 4: Opening the Foundation

Along the entire perimeter of the building, every 2 m it is necessary to prepare holes into which channels or I-beams should be inserted; they will act as a platform. With the help of hydraulic jacks, these iron structures evenly lift the house to a height that allows strengthening the foundation itself. Temporary supports (welded structures or wooden blocks) are installed under the house. When full access to the foundation is obtained, reinforcement can be fully carried out. Having finished the work, you just need to put the house in place and bring in all the things.

But what about the types of the foundation itself, since most often it is columnar and strip? Will their strengthening take place in some specific way? Many people know that columnar is a system of piles (pillars) that are installed in areas of maximum load. To properly distribute the load on these supports, various devices such as grillages and strapping beams are used. The design of the tape is also intuitively clear from the name. This reinforced concrete structure in the form of a closed loop. Columnar is often combined with ribbon.

Fortified strip foundation

If you want to deploy reinforcement to any of these designs, then both methods described above will work for this. In addition, it can be improved by drilling holes in the posts and equipping them with reinforced rods. How to strengthen it, you can even choose from several options: by replacing parts with new ones (block), or by erecting formwork and pouring a layer of concrete (monolithic).

Most capital buildings require strengthening of the foundation over time. Older houses are especially in need of renovation. It is imperative to strengthen the foundation of the house if its owner intends to add another floor, and the foundation of the building is only designed to withstand the weight of a one-story building. Strengthening is indicated for the foundation, which was erected with violations of technology and without taking into account the climatic features of the area and soil conditions.

As a rule, a homeowner decides to strengthen the foundation of an old house with his own hands when cracks appear on its walls and on the foundation itself, or the building is noticeably tilted, and the door and window openings are skewed.

The work of renewing the foundation under a structure is labor-intensive, but not as impossible as it may seem.

How to strengthen a concrete foundation?

A dilapidated foundation will become stronger if it is surrounded by a new reinforced concrete tape firmly connected to it. This method of updating the base is the simplest and relatively cheap. However, any work to strengthen the foundation of a house is associated with the risk of the building collapsing. The main thing that the master must learn is that strengthening the support for the walls should be carried out consistently and without haste.

First of all, you need to strengthen the base of the corners of the building:

To do this, holes are dug at each corner, the bottom of which should not be higher than the base of the foundation;
pits do not need to be made wider than 0.5 m (it must be said right away that strengthening all corners should not be carried out at once, work should be carried out one by one, and only after strengthening the first corner can one proceed to strengthening the opposite one, and so on);
the surface of the old foundation must be cleaned of soil, concrete chips and dust;
using a hammer drill, holes are drilled in the thickness of the base at a distance of no more than 0.25 m from each other;
pieces of reinforcement or anchors are driven into them, which will subsequently connect the old base to the new concrete ring;
in each pit into the bottom of which reinforcement sections are driven, a frame made of reinforcement with a cross-section of at least 12 mm should be tied with steel wire;
in order for the corner supports to be subsequently connected to the new foundation into a monolith, the reinforcement of their frames is extended to the sides by 0.5 m;
The pits prepared in this way are filled with concrete.

If old house occupies a large area, then supports similar to those installed at its corners must be built every 4-4.5 meters along the perimeter of the building.

After the concrete poured at the corners has become strong enough (after 3-4 days), you can begin to strengthen the foundation of the old house along its external walls. From support to support, if the condition of the existing foundation allows, a trench is dug (if there is a fear that the wall will collapse, it is better to dig a trench no more than 2 m long). Its bottom should also not be higher than the base of the old foundation. Further operations exactly repeat the work of strengthening the corners. Before filling the trench with concrete, the frames of the corner supports should be connected to the reinforcement of the new foundation.

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Replacement of individual piles at the base of the house

The foundation repair method described above is suitable for updating the foundation of both a brick and a wooden house, if, of course, a strip foundation is laid under the latter.

Strengthening foundations: a – simple widening; b – deepening and widening; c - widening with reinforced concrete beams; d, e - transfer of load from the weight of the wall to piles made on both sides; e - transfer of load to reinforced concrete tides; g, h – conversion of a strip foundation into a slab foundation. 1 – wall; 2 - foundation; 3 – transverse unloading beam; 4 – making a groove for the key engagement; 5 – monolithic concrete; 6 – longitudinal beam; 7 – bolt; 8 – frame; 9 – monolithic pillow; 10 – reinforcing reinforced concrete beams; 11 - piles; 12 - monolithic reinforced concrete beams; 13 – reinforcing reinforced concrete slab.

However, not every wooden house stands on such a foundation. Often the structure rests on pile foundation, which was made from logs. Strengthening a foundation of this type if individual elements of the foundation are damaged is quite simple. The log is removed from under the crown of the wooden house after it is raised with the help of a jack.

To install the lift close to the log to be replaced, you need to prepare a solid base, and insert a wood spacer between the jack and the crown.

After removing the pile from under the house, the bottom of the well is strengthened with concrete. The new support is put into place only a few days after pouring. This method of replacing columns is acceptable when 2-3 piles need to be replaced, but more often many more supports become unusable, and their partial replacement does not solve the problem of dilapidation of the foundation of an old house.

Often, in order to strengthen the foundation of a wooden building, a method is used in which bored piles are installed in place of old columnar supports. They are much more durable than a brick or log foundation, but to install them around the entire perimeter of the house, you will need a mindset for long-term work.

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Updating the columnar foundation with bored piles

The process of replacing piles with bored ones is generally similar to that described above, but has some nuances:

after jacking up a section of the wall near the pillar to be replaced, a dig is made under it and the old pile is removed;
the bottom of the hole for the new support should be 0.3-0.5 m below the level of the base of the old pole;
the outer wall of the pit on which the pipe will be laid must be inclined;
the new pile will be installed on a platform of 0.4x0.4 m.
a sand cushion is placed under the base of the pile, which must be thoroughly compacted;
A 200-mm asbestos-cement pipe is lowered into the hole at an angle;
a little concrete is poured into it;
immediately after it hardens, several pieces of reinforcement are inserted into the pipe and filled to the brim with concrete mixture;
after this, the resulting monolithic pile is transferred to a vertical position and installed under the crown;
the pit dug for it is filled up.

The remaining foundation pillars are replaced using the same method.

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Screw piles - a modern solution

You can strengthen the foundation of a house by installing it around its perimeter screw piles, which are corrosion-protected pipes with welded blades on them:

piles are screwed into the ground 150-200 mm from the walls;
the distance between them should not exceed 3 m;
before installing the piles, it is necessary to prepare a small hole 0.5 m deep for each of them;
these supports must be screwed to a depth exceeding the soil freezing level;
after screwing, all piles must be leveled horizontally (laser or hydraulic levels can be used for this);
The body of the pipe of each pile is filled with concrete, and a head is welded to its end - a steel plate, the dimensions of which are slightly larger than the cross-section of the pile.

Replacing the old foundation with screw piles.

Now the old house needs to be raised to connect the piles into a single frame. Of course, before lifting, the structure must be freed from excess weight (remove furniture from the house, if possible, dismantle the floor). Raising an old wooden house on the desired height This is done with the help of jacks and beams placed under the crown. This operation must be performed with care to avoid distortions. You should not lift each section at a time to a height exceeding 2 cm. All temporary supports under the crown of the structure must be as stable as possible.

The next stage of work is the installation of I-beams under the house, which are attached to screw piles and will serve as support for the structure. The entire structure along the outer perimeter should be scalded with channels. The building is then carefully lowered onto the new foundation.

The convenience of using screw piles when repairing foundations is associated with relative simplicity and the speed of their installation. The advantages of this type of foundation lie in the possibility of its construction on unstable or waterlogged soils. The construction of a foundation made of screw piles is not associated with excavation work. Almost immediately after installation, piles, unlike a concrete foundation, are ready to withstand heavy loads.

Before starting work to strengthen the old foundation, it is important to analyze the reasons that led to its destruction. Only after finding out all the circumstances can we expect positive result repair work.

Analysis of the reasons leading to the destruction of the foundation

Foundation destruction

Changes in soil characteristics for the following reasons:

increase in loads on the foundation due to the significant mass of the structure. Their increase, accordingly, leads to an increase in pressure on the ground;
improperly organized drainage or raising the passage horizon groundwater. Water, acting on the soil, leads to its erosion;
the proximity of other structures, as well as the construction of extensions to the house, lead to an increase in loads on the ground. In this case, the soil located under the foundation is squeezed out;
seismic impact.

Deterioration in the strength characteristics of the foundation material associated with errors made during the design, namely:

Types of foundation deformation

In addition to finding out the reasons that led to the destruction of the foundation, it is necessary to give an adequate assessment of its extent. This will allow us to determine the possibility of strengthening the foundation and the feasibility of this event. Maintainability is determined in accordance with the following criteria:

1. Damage is minor

This includes violating the integrity of the foundation finishing. The presence of phenomena of this kind does not affect the strength of the foundation and does not reduce its bearing capacity. Eliminating them is easy.

2. The damage is moderate

The occurrence of cracks is associated with the process of subsidence or destruction of the base. Before starting work, it is necessary to differentiate the nature of the cracks. Their horizontal arrangement poses less danger than their vertical or zigzag arrangement. In addition, it is important to find out what the nature of the process of foundation subsidence is. That is, this phenomenon is temporary or progressive.

Average damage

To clarify this circumstance, beacons are used. Plain paper can be used as them, but there is a risk of it getting wet. The use of plaster plasters is recommended. The simplest method involves applying a small amount of putty to the surface. Then, using a spatula, a mark is made in the form of a straight line. Even a slight shift of the tested surface will be noticed. In addition, when using this method, you can find out at what speed the destruction process occurs.

Temporary subsidence will not be detected by beacons. In this case, most likely, some shift of the soil located under the foundation occurred, it was fixed in a certain position and the likelihood of further movement is low. Therefore, to eliminate defects, it is sufficient to carry out routine repairs.

When lighthouses are destroyed, it can be argued that the destruction process is progressing. Sealing cracks will not give the required effect, since the deformation is close to catastrophic.

3. The damage is catastrophic.

The presence of defects of this kind can cause destruction of the structure. Timely work to strengthen the foundation will prevent the occurrence of extreme negative consequences. However, in practice there are situations in which this opportunity is missed.

The choice of technology depends on the type of foundation. In this case, each specific case considers its strengthening or replacement.

4. It is not possible to eliminate deformations

The condition of the foundation is so poor that repairs are impractical. In such situations, the most correct solution is to demolish the building. From an economic point of view, dismantling a house is much cheaper and simpler than measures to strengthen the foundation. The construction of a new cottage on the site of the previous one in accordance with building codes and regulations will allow you to have comfortable and safe housing.

Sometimes the only right solution is to demolish the building

Preventive measures: strengthening the foundation or eliminating the causes?

There is only one way to prevent foundation damage. Strict adherence to certain rules at all stages of its construction:

Violation of technology during the construction of the foundation is not allowed. The concrete must be freshly prepared, and its grade must correspond to the design grade. There is a significant difference in the load-bearing capacity and hydrophobicity of different brands of this material. Unreasonable savings on materials during foundation construction can cause catastrophic consequences.
Drainage and waterproofing are required. The cost of constructing a foundation is not comparable with the costs of carrying out these activities; the absence of a cushion and protection from moisture will lead to a sharp reduction in the service life of the foundation.
Should not be neglected in order to save cash carrying out qualified geological surveys. Information about the structure of the soil, the occurrence of groundwater and the depth of freezing, as well as recommendations for arranging the foundation, received from a competent specialist, cost significantly less than strengthening a cheap house foundation.
The installation of communications should be carried out before the foundation is poured or laid. Carrying out excavation work can negatively affect the condition of the foundation.
The design load must correspond to that provided for by the project. Rebuilding a house with an increase in number of floors or replacing finishing materials can lead to destruction of the foundation due to exceeding the permissible loads. To avoid such consequences of making an erroneous decision, it is necessary to consult an architect.

Ways to strengthen the foundation of a house

Builders have a wide range of tools and methods to strengthen the foundation of an old house. At the same time, time-tested methods do not lose their relevance. To choose the most optimal one, it is necessary to understand the advantages and disadvantages of each of them in relation to a specific case.

Ways to strengthen the foundation

Strengthening the strip foundation

The foundation of most private houses is. The characteristics of such foundations have the technical possibility of locally exceeding the normative loads. This type of foundation may experience local soil heaving. All types of foundations are built on bedded stone. When it draws down, it is important to stop this process in a timely manner.

Strengthening strip foundations

To do this, a hole is dug at an angle of 35 degrees in close proximity to the foundation. Its depth should reach the level of laying the bed stone. Then a pipe with a diameter of 150-200 mm is placed in the resulting pit. With its help, a thin concrete solution is poured, which is continued until the soil is completely saturated with it. At this stage, it is necessary to suspend all work for a couple of hours. At this time, observation should be made of the behavior of the soil in terms of saturation with the solution.

If the solution leaves, then continue filling the hole after a few days.

As practice shows, to completely saturate the soil, the procedure must be repeated two or three times. Control over the situation is carried out by beacons. In case of a slight change in their position, they move on to the next stage.

A ditch with a width of 200-350 mm is dug along the contour of the foundation. At its bottom and on the outside, a structure similar to formwork is constructed from boards. Pins are driven into the foundation, and a reinforcing mesh is attached to them. The resulting reinforcement is filled with concrete mortar filled with fine gravel and crushed stone. Such a structure will make it possible to significantly strengthen this corner of the house and evenly distribute the loads in the horizontal plane, which will stop the process of subsidence of the house.

Restoration of a foundation with cracks

Cracks in the base and misalignment load-bearing structures may have a different character. Therefore, the first priority is to find out the nature of the processes taking place in order to find an adequate way to strengthen the foundation of the house.

Restoration of a foundation with cracks

If there is destruction along the perimeter of the foundation due to increased loads or exposure to moisture, they dig a trench that follows its contours. After this, the surface is thoroughly cleaned to remove the layer of plaster and adhering dirt. Next metal mesh fixed with anchors driven into the base. Finally, the concrete solution is poured layer-by-layer with careful compaction.

If the foundation material is rubble stone, monolithic slab concrete or combinations of concrete-based materials, then a widened reinforced concrete frame is used. In this case, it is necessary to carry out reliable fixation, using through anchoring, with the material of the old masonry. The idea of building such a structure is that the old and new foundations work as a single whole.

In some cases, there is a need to strengthen areas where the foundation is weakened. For this purpose, a new foundation is created locally. Its task is to redistribute loads and partially unload the old foundation.

Partial foundation replacement

If the foundation fails completely, it becomes necessary to replace it. To accomplish this task, it is completely unloaded, and at the same time the stability of the structure is preserved.

Unloading

This activity can be accomplished by installing so-called chairs, which are made of wood. Their installation occurs perpendicular to the foundation tracks. To secure the building, pillars placed under the walls can be used. The use of braces to hold the base and transmit forces at an angle to the ground is not excluded.

Before starting repair and restoration work, beacons should be installed. This is necessary so that the likely deformation process during this work can be detected. After this, they begin directly to implement the planned activities, which begin with digging a pit. The foundation is laid in sections, the length of which should not exceed two meters.

During excavation work, walls must be reinforced with struts. Next, a dig is made under the foundation and the soil is removed. Then the formwork and base for the foundation being constructed are installed. The sole is cleaned and, where required, dismantled. The old and new masonry are fixed together using a rigid cement mortar and crushed stone. Having completed the foundation in one place, it can be continued in another.

During long-term use various types In structures, deformation of the structure occurs quite often.

wear and tear of building materials;
marriage;
mechanical deformation.

Reasons that can cause them:

Mistakes during building design
Production errors
Incorrect operating conditions
Design errors

Regardless of what reason influenced the occurrence of deformation, most likely it will be necessary to strengthen the foundation. This procedure can stop the destruction process or reduce it to a minimum. At the same time, all work is associated with increased risk, so it is better to entrust strengthening the foundation of the house to specialists.

The method of strengthening the base always depends on the condition of the structure, its reconstruction, restoration or conservation. Reconstruction may be associated with an increase in the load on the existing foundation due to superstructures, replacement of wooden floors with reinforced concrete ones, changes in technology, etc.

The main factors when choosing a strengthening method are those that are related to the structural features of the building, as well as the condition of the soil and the equipment of the companies carrying out this activity.

Today, thanks to equipment and innovative developments, it is possible to carry out work to strengthen the foundation of a building quite reliably, quickly, technologically and with minimal use of manual methods.

Modern calculation technologies make it possible to model the latest options for strengthening foundations based on geotechnical information. However, without a detailed calculation justification, one should not abandon traditional methods, since in combination with more modern ones, they quite often give a positive result.

Reasons for strengthening the foundation

There are various reasons why a foundation may require strengthening:

when constructing pits in close proximity to the house or trenches;
when leveling a house due to its tilt;
when cracks form as a result of disproportionate deformation of the base of the structure;
when the strength of the foundation building material decreases during the period of operation of the house;
increased soil deformability;
construction of another structure next to the existing building, which provides additional load on the foundation;
when reconstructing a structure with an increase in the mass of the building or payloads on it;
when the foundation weakens during the operation of the house, resulting in deflections in its elements or unacceptable precipitation;
deterioration of the conditions of fundamental stability or the soil at its base.

Most often, external damage indicates the need to strengthen the foundation of a building:

jamming of windows and doors;
their distortions;
cracks on windows and walls.

In this case, the structure clearly begins to experience deformation, so it should be monitored regularly.

As for industrial buildings, in addition to the main ones, they also exhibit other signs, for example, tilting of pipes or towers.

How to strengthen the foundation of a house

Proven methods of strengthening foundations, as well as protection against soil weakening, are:

retaining walls;
loading;
anti-filtration curtains;
drainage;
smolization;
silicization;
cementation.

The basic methods of strengthening foundations are:

correction of deformities;
placing piles;
protection of foundation material from weathering;
expansion of the supporting area;
deepening the foundation;
strengthening the foundation to increase its strength.

Recommendations on how to properly strengthen the foundation:

remember that the choice of method for strengthening the foundation depends on the condition of the structure, its possible subsequent reconstruction, as well as on the structural features of the house and the condition of the soil;
try to limit yourself to sealing cracks with cement mortar, especially if they are minor or the shrinkage of the foundation has stopped. Before doing this, unstitch them and fill them with the mixture in a ratio of 1:3;
If a large settlement occurs, then eliminate the causes of its occurrence. For example, when the foundation is deformed due to soil washout, the technology of pumping cement mortar into the resulting voids is used. Wells are created in the foundation and under high pressure the solution is pumped into them. This layer strengthens the base and serves as an excellent waterproofing layer;

if you do not have special equipment for injection and drilling, then this activity can be performed manually. To do this, along the perimeter of the foundation, or exclusively in problem areas, the soil is excavated below the base. The trench is filled with masonry or monolithic concrete.

How to strengthen the foundation of an old house

Strengthening the base of massive structures is created using the additional installation of bored piles:

initially, along the perimeter of the building, next to the old foundation, wells are made in a checkerboard pattern with a diameter of 10-30 cm every 100 mm;
then reinforced;
then they fill it with concrete;
Then the bored piles are fixed to the foundation with anchors.

You can also strengthen a weak foundation of a house using reinforced concrete clips:

first you need to dig a trench along the strip or along the perimeter of the columnar foundation;
then thoroughly clean the surface of old dirt and plaster;
then you should hammer reinforcement anchors into the structure;
install a metal mesh along the foundation, securing it with anchors;
create formwork and concrete;
then, after the concrete has hardened, the trench is backfilled and compacted layer by layer.

Anchoring must be done in such a way that the new sections of the foundation support the mass of the structure together with the old ones.

Methods for properly strengthening the foundation:

1. Expansion of the foundation area:

Reinforced concrete blocks should be installed on the inside and outside of the foundation;
their lower part is tightened with fasteners that pass through the existing foundation - this is how the structure is connected to the old one, thereby strengthening it;
the upper part of the blocks is expanded so that the lower part clamps the soil under their base;
then the places of the auxiliary blocks and the old foundation are filled with a mixture of concrete - this creates the integrity of the structure.

2. Soil strengthening

Using injections, a special hardener solution is introduced into the soil from:

hydrochloric acid and urea resin;
bitumen emulsions;
liquid glass and calcium chloride;
cement mortar.

In this way, the foundation is strengthened directly under the foundation.

3. Installation of the foundation slab

This technology involves replacing the strip foundation with monolithic sectors that create a complete slab. This happens sequentially by removing sectors of the old structure and replacing them with sectors of the new one.

4. Strengthening the foundation without adjusting dimensions

This technology is used in cases where the foundation has mechanical damage (destruction of masonry, cracks) or its building materials are in unsatisfactory condition.

Here, the foundation masonry is strengthened by injecting a cement solution through installed injectors.

5. Strengthening with concrete clips

In this case, the foundation masonry is completely or partially replaced. If the first option is created, then it must be produced in separate sections.

6. Laying the foundation

The foundation is divided into sectors of 1-1.60 m each. Work is carried out simultaneously on sectors that are distant from each other, so as not to subject the foundation to excessive load.

7. Reinforcement with piles

Used when there is a significant increase in the load on the foundation or its global wear. The piles are installed using the injection method - thus, they will serve as an additional foundation. Wells are drilled through the old base and compacted by filling it with a fine concrete-sand mixture.

How to strengthen the old video foundation:

Over time, the foundation structure begins to deteriorate. Failure of the foundation occurs due to the old age of the house, untimely repairs and strengthening. If the walls of the building are strong, home owners try to strengthen the foundation. Using this construction procedure, you can increase the life of the house and save money on a new building.

The main reasons for the destruction of the foundation

Quite often, the foundations of old houses are subject to complete or partial destruction of the foundation. This occurs due to the following violations:

non-compliance with the construction technology of the facility;
incorrect calculation of the load on the base;
incorrect house design;
change in soil level;
lack of soil research;
dilapidated condition of the building.

Sometimes the owners of mansions want to add a second floor; increasing the load on the walls and foundation leads to strong sagging and the formation of deep cracks. Before you begin work on strengthening the foundation, identify the cause of its occurrence.

Ways to strengthen the foundation

For each type of house there is a specific method for strengthening the foundation. All buildings can be divided into:

brick;
wooden;
stone.

For example, fix defects on wooden house possible by moving it or lifting it. This method is not suitable for stone or brick houses. Each building has its own type of base and all repairs must be carried out taking into account the design of the house.

Strengthening the pile foundation

Before starting work, it is necessary to find out what is wrong with the load-bearing piles of the house. They can either sag or sink a little and change shape. To clarify the situation, as a rule, a pile is driven in next to the foundation, and then a comparison of correctness is made. This means that at the initial stage of construction the main piles could have been driven to the wrong depth, as a result of which the freezing point of the soil was not reached and there was no stop when driving them. If the piles have changed their shape, they must be driven into the ground until the ground is solid. This action will help resolve the problem. If a collapse occurs, then special linings made of metal or wood are installed under the piles.

For detailed instructions on how to do this, watch the video material.

Reinforced concrete support for strip base

To eliminate emergency situation and reinforcement of the strip foundation, reinforced topping is used. Strengthening the foundation of a private house is carried out in the following way:

dig around the foundation of the house;
remove the old concrete, widen all the cracks and drill through the base.
insert reinforcing bars into the resulting holes;
remove as much as possible all protruding parts of the base;
We weld the frame to the reinforcing bars;
We make formwork and fill everything with concrete.

Important! Don't skimp on the frame, because... he is the one who does it important function in strengthening the foundation.

Strengthening the brick foundation

The brick base can also be strengthened. For this purpose, durable bulls are made, which are subsequently extended onto the house. Bulls are a concrete block that is built up onto the corners of the plinth to increase the support area and strengthen the structure. How to install bulls correctly?

At each corner, a hole is dug 0.5 m deep from the previous foundation.

Important! The size of the pit is taken into account based on the load and bearing capacity of the soil.

We fix the formwork into the hole.
We install the volumetric frame.

Expert advice! Under no circumstances should you connect the new frame to the old foundation, because... the new structure will sag a little, which will lead to rupture of the old concrete.

The entire plane is filled with concrete, after 7-8 days it is necessary to remove the formwork and backfill.

Such work should be done quickly and smoothly, because... a house with ripped corners loses its strength and stability.

Sometimes after installing the bulls, experts see that this is not enough to strengthen it. In this case, a comprehensive strengthening of the straight sections of the base is performed. This procedure has several distinctive nuances from installing bulls:

It is forbidden to dig up large sections of the wall; this can lead to the formation of large cracks and the collapse of the foundation. The permissible value is 2 m on one side;
when strengthening the base, it is permissible to connect old concrete with a new structure; it is necessary to tie not only them together, but also individual sections;
installing waterproofing at the joints between blocks, this will protect against the appearance of deep cracks, water ingress, loosening of the foundation and its destruction.

Dry injection method of strengthening

This method is popular among specialists. It can only be accomplished with the help of professionals and the use of special equipment. The work process is as follows:

Wells with an inclination of up to 25 cm in diameter are drilled through the old base. The drilling depth is individual in each case; it is important to reach a solid layer of soil.
The solution is poured into the finished wells and a reinforcement cage is installed.
As a result, the entire old structure rests on an additional number of piles.

Concrete reinforcement

The base can be strengthened using a monolithic frame. This method makes it possible to pour concrete on the side of the building. The entire work process is divided into the following steps:

a trench is dug across the entire area of the building;
the surface of the base is cleaned of soil, dirt and concrete;
drill holes and install anchor rods in them.

Expert advice! If you have the opportunity to carry out work from inside the building, use special through studs.

permanent formwork is assembled in the trench;
a volumetric frame is fixed into it;
then it is tightened with studs and construction anchors;
the entire plane is filled with a solution, which is vibrated to fill all the cracks;
after the concrete has dried, it is necessary to waterproof it and build a durable blind area.

Strengthening the base on one side

Sometimes a house can only sink on one side. In order to strengthen the structure, it is divided into several sections at a distance of 2 m. Next, the following work is performed:

a trench is dug deeper and wider from the old base for the initial element;
holes are drilled in the old foundation for reinforcement, with the help of which the old structure is tightened;
they make fines to increase the adhesion of the entire area of the building;
Next, we take the reinforcement frame and rods, they must fit into the damaged base, we install them and cement them;
The formwork is fixed and everything is filled with concrete.

As soon as the concrete has dried a little, proceed to the manufacture and construction of the same new elements to strengthen the building. When all the work is completed, all elements are connected to each other by releasing reinforcement from them.

Complete replacement of the base

The foundation of a house is replaced when it is no longer possible to strengthen and restore it. The whole process is labor-intensive and long. To do this, you need to dig a trench along the entire foundation strip up to 2 m deep, remove the old structure and pour a new foundation. To prevent this method of strengthening, it is necessary to monitor the structure. If cracks or distortions of windows or doors occur, carry out restoration measures.

As you can see, strengthening the foundation can be done on your own, the main thing is to carry out the work step by step, taking into account the technology and the characteristics of the damage that has occurred.