Place the foundation for the house in a swampy area. Which foundation is better in a swamp? Nuances of structures on soft ground

A house can be built in any area. It is good if there is stable soil and the installation of the foundation can be carried out according to the usual standard norms and requirements. Another thing is unstable, swampy soils. This requires additional costs not only for equipment, but also for proper design, taking into account the specifics of the construction site. Swampy areas are not the most suitable basis for construction. But even here, subject to all norms and requirements, it is possible to build a high-quality, strong foundation that will serve as a reliable foundation for the house for many years. The main requirement is the right technology building foundations on unstable, wet soil. The article describes in detail what kind of foundation to choose for a foundation on swampy soil when planning construction in such a problematic place.

Swampy soil is a difficult base for a foundation. In this case, two types of foundations can be used: pile and slab. Pile foundation reinforced with metal or concrete piles, the slab is made in the form of a monolithic reinforced concrete slab, which is poured onto a sand-granite cushion.

Slab

A slab foundation is designed to ensure that the load of the building is uniform across the entire base of the slab. Such a base can withstand increased loads and is used not only in individual, but also in industrial construction.

Slab technology is applicable on heavily swampy soils, unevenly compressed soils, and with a high groundwater supply. However, the disadvantage of such a foundation is that it is inappropriate to install it on slopes. If there is even a slight slope, the slab can “slide”. The special advantages of a slab foundation include its high load-bearing capacity. The only drawback here is the increased consumption of materials, which is a very painful fact for individual construction.

To pour such a foundation, you will need many times more reinforcement and concrete than when installing a foundation on solid soils, which, naturally, will entail an increase in the entire final cost of the building.

Pile

Installing a pile foundation in swampy areas is more reasonable and has its advantage in the direction of uneven terrain. Piles can be placed in any hard-to-reach place, on slopes, on any technically difficult soil. Among the advantages of a foundation on piles is not only its installation in hard-to-reach areas with complex terrain and unstable soil, but the advantage is the speed of installation of piles and an affordable price.

The opinion that a pile foundation is more suitable for small, lightweight structures is incorrect. By increasing the number of supports, the highest possible bearing capacity of the foundation is achieved, which is in no way inferior to the parameters of the slab base. However, at the same time, the costs of such a foundation will increase and its cost will be equal to that of a slab foundation. When constructing reinforced, heavy structures, this fact should always be taken into account when it comes to the cost-effectiveness of a pile foundation.

Preparatory stage

At the first stage of construction, a full soil study is carried out. For this, a hand-held probe can be used to take soil samples. This method is used in the construction of light wooden buildings and structures.

The probe is lowered into a well 5 m deep. During capital construction of stone or brick houses serious geological exploration is required. In this case, the depth of measurements is 8-10 m. Wells for measurements are located in the corners of the future structure. There must be at least four such measurements (wells). Determine indicators of soil composition and depth of its layers; level, quantity and composition of groundwater. One more indicator is needed - this is the freezing point of the soil.

The upper layers of marshy soil are mainly peat. Clay and sandstone may follow. Peat is a porous, completely loose material with low compression resistance and increased instability. If the layer thickness is small, the peat is removed and the foundation is placed on the lower hard rocks. This is a shallow foundation. Its peculiarity is that the slab under the foundation is located above the freezing point of the soil. This base is suitable for light buildings.

A shallow foundation is arranged so that it can rise and fall slightly during heaving processes occurring in the soil. Thanks to this, it does not crack and retains its shape. This base is not used for brick and stone houses. If the peat layer on the construction site is deep enough (more than 5 meters), it is necessary to strengthen the foundation with piles.

Not only the peat layer is a problem when building a foundation on swampy soil. The second problem is the nearby groundwater. There are two ways to combat this problem:

lower the water level;
raise the area.

The device helps to significantly reduce groundwater levels drainage system. To drain water from the construction site, trenches are dug to a depth of about two meters, and the entire drainage system is led to drainage wells. Fill the trench with a layer of crushed stone and lay it on top drainage pipes. Drained water from wells is pumped out using submersible pumps.

To raise the site, you need to make an embankment of stone and sand. To do this, remove the top, weak layer of soil and fill the area with a layer of stone and sand. Such an embankment is carefully compacted and compacted with rollers.

Slab foundation installation technology

The slab foundation must be made in accordance with all standards according to the following basic scheme:

Removing the soil layer. Depth 1 m.
Making a mound (pillow) from a mixture of gravel, stone and sand. The embankment is compacted and concrete preparation is made.
Covering with waterproofing and thermal insulation.
Making a frame from reinforcement. Tying the frame with wooden blind areas.
Pouring concrete over the frame and its subsequent compaction with an industrial vibrator.
Leveling the surface as a rule.

Installation of a pile foundation

The main thing here is the piles. They can only be reinforced concrete or combined. There are three types of piles:

screw metal;
driven reinforced concrete;
bored

Bored piles with asbestos-cement formwork are installed only when draining the supporting soil layer. They have fairly good load-bearing capacity. Screw metal piles are somewhat inferior in their load-bearing characteristics to bored piles, but they have high installation qualities: speed and ease of installation, ease of transportation.

A distinctive feature of screw supports is the ability to extend them to the required length. Driven piles are installed using pile driving equipment. At the same time, it is not always possible to use heavy equipment in individual construction.

The main criteria when calculating the number of support piles are the type and magnitude of the load. Regardless of the type, piles can be installed in the following order:

Rows under the walls.
Alone under a support.
Bushes under the columns.
Fields under strong vertical loads.

All calculations of the length and volume of piles are performed based on geological survey data in accordance with construction standards and regulations. The lower ends of the piles should rest on dense soil. It should be noted that on each of the foundations considered, any residential building in a swampy area can be installed. Any of construction technologies suitable for building a house, restrictions can only be related to the operating conditions of the building being constructed.

In conclusion, it should be noted that not all building materials are suitable for buildings in wet areas. For example, at high humidity it is not recommended to use foam concrete, expanded clay concrete, or aerated concrete due to the strong hygroscopicity of the material. The timber is also not the most the best material. On swampy areas it is best to build brick, stone or frame houses. But the most important thing is to lay the foundation correctly and absolutely accurately. To a greater extent, it is precisely because of this that a house built according to all the rules will last a long time and reliably.

Construction of the foundation is one of the main construction tasks, which ensures the durability and reliability of the entire building. But not only from the correct execution installation work The strength of the base depends. In this case, the soil plays an important role, namely its characteristics. Therefore, when choosing the type of foundation, you need to focus on this parameter.

Features of the foundation in the swamp

The foundation for a house in marshy areas requires special attention. After all, in addition to the load-bearing load from the mass of the house, it also experiences the plasticity (mobility) of the soil, which can lead to the following problems in the future:

Partial or complete flooding of a house during the heaving season when the groundwater level rises;
Uneven distribution of load on the base, which can lead to destruction of the task in the area of the foundation or along load-bearing walls;
Constant dampness in the house and the spread of fungus from the floor, etc. However, such problems can be avoided if you choose the right type of foundation for a house on swampy and waterlogged soils.

The fact is that the composition of the soil in swampy areas is quite diverse and can include peat layers, sand, clay, quicksand, etc. Such combinations inevitably lead to constant soil movement. Therefore, it is so important at the design stage to conduct a preliminary soil analysis by drilling several control wells and taking soil from them for analysis. You can order soil tests on a construction site from special organizations. The service, of course, will cost a pretty penny, but in the future the architect will be able to correctly calculate the bearing capacity of the foundation.

Types of foundations for swampy soils

It is possible to build a house in a swampy area if you adhere to all the nuances of installation technology. And as the foundation for a house, you can choose these types of foundations.

Pile base

The best option for foundation for a house in a swamp. This foundation is based on monolithic reinforced concrete or bored piles. Sometimes their depth can reach 15-20 meters, depending on the number groundwater on the site and the degree of heaving of the soil. But a house on such stilts will feel safe and strong for many years. Even with severe heaving, the building will remain in place. The pile foundation can be installed both in summer and at sub-zero temperatures. The work is completed in 2-3 days.

Important: below the 20-meter mark, the pile has simply already overcome the marshy soil layer and rested on dry layers, which makes the supports even more reliable. However, it is worth remembering that it is impossible to build such a foundation on swampy soil on your own. This will require sophisticated drilling equipment. Although the cost of purchasing all the material itself is not that high.

However, it is worth remembering that piles are not recommended to be installed in soils that are prone to horizontal shifts. In this case, even the strongest piles over time may not withstand the horizontal pressure of the layers and simply break. Which will lead to the destruction of the house over time. On such soils it is better to install a foundation slab.

Slab monolithic foundation

This type of foundation fits perfectly on swampy soil and is a monolithic reinforced concrete pad. It is also called a floating foundation, due to the ability of the base to maneuver in the soil during heaving seasons. That is, the base will simply follow the movement and direction of the soil, withstanding significant loads. The depth of such a slab should reach 1.5-2 meters in order to go into the ground below the soil freezing level. It is better to pour a slab-type foundation in the summer, when the groundwater level in a swampy area goes as deep as possible and gives craftsmen the opportunity to work dry.

Important: it is desirable that the base of the foundation extends beyond the design parameters of the building by 40-50 cm.

As another type of foundation for construction in swampy areas, a shallow-depth slab foundation. This is the same floating slab that goes only 50 cm into the soil. But it is worth remembering that such a foundation can only be built for lightweight frame or timber houses on one floor. The large mass of the house (if you install a brick or block cottage) will simply break the foundation due to resistance from the soil during heaving seasons.

Do-it-yourself foundation installation: choosing the type of work

If you don’t know which foundation is best to install in swampy areas with your own hands, then give preference to a slab. This type of base, even with large volumes of work, can be completely done with your own hands. As special equipment you will only have to rent an excavator to prepare the pit and a construction mixer with ready-made mortar. Otherwise, you can do everything yourself

If you prefer a pile foundation, then you should know that it is better to entrust the work to professionals. Since only craftsmen can clearly control the evenness of the well under the pile, its depth and the uniformity of filling the column with mortar. In addition, only a competent operator can work with drilling rigs.

Carrying out work on the installation of a slab base

In this section you will learn how to make a monolithic floating foundation in a swamp. First of all, it is worth understanding that it is better to carry out work in the second half of summer in dry weather. It is during this period that all groundwater is located as deep as possible.

It’s good if the developer already has project documentation. It is along it that the axes are broken down in the area under the base. That is, stakes are installed along the entire perimeter of the future foundation and control cords are pulled between them. Do not forget to increase the base slab by 30-50 cm on all sides.
Now is the time to remove the soil to the specified design depth. For this, it is better to use a bucket, since you will have to do the excavation work yourself within 2-3 weeks. Yes, and physically it is quite difficult.
The bottom of the prepared pit is well compacted and covered with a layer of crushed stone 20-30 cm thick. It is also compacted well. And the next layer of the pie becomes a layer of sand of the same thickness. It is moistened and compacted until there are no traces on the sand when stepped on. When performing this stage of work, you need to use a shovel to clearly level the walls of the pit for installation of formwork.
Now formwork is installed in the pit, which should be higher in height than the ground. This is done to form a base 30-50 cm high.
The bottom of the pit and the walls of the formwork are covered with roofing felt, the joints are overlapped and coated with bitumen mastic. Such waterproofing will prevent contact of the concrete base with groundwater and prevent the flow of concrete milk into the ground, which could reduce the final strength of the foundation.
Then steel reinforcement is installed in the pit in the form of meshes connected from steel rods. For every 50 cm of foundation thickness there should be one mesh connected to a cell size of 20x20 cm. All transverse meshes are connected to each other by longitudinal rods. It is important to remember that the reinforcement should be buried in concrete 5 cm from the top and bottom and 2-3 cm from the sides of the slab.
Now you can fill the monolithic base with the prepared solution. Taking into account the fact that tens of m3 of it will be required, it is better to order ready-made concrete. Grade 400 or 500. This type of mixture will provide greater load-bearing capacity of the base. The solution must be poured in one stage, since step-by-step mixing of the solution and its pouring lead to a violation of the technology for installing the slab base and a decrease in its final strength.

The poured base is covered with film and left for 3-4 weeks until completely dry. In the first days, the slab must be periodically moistened to prevent the mixture from drying out suddenly. After a month, the slab is completely ready for further construction work.
Once the slab has completely hardened, you can backfill the base. For these purposes you can use clay soil, which will act as additional waterproofing for the monolith. In this case, the clay must be compacted well when backfilling.

Important: shallow slab foundations are also installed using the same principle. Remember, a well-made base is the key to the longevity of a house on marshy soil.

If you have been given a marshy area to build a house on, there is no need to be upset; with modern technologies it is possible to build a house on a marshy area. The main thing is to choose and build the right foundation - the foundation for the house. And we will tell you which one is better on marshy soil.

Description of swampy soil

This is a multilayer heterogeneous structure, which includes clay, peat, sandstone and has different densities. It is oversaturated with moisture, with a large number of fine-grained particles that weakly resist compression. The instability of the soil makes it difficult to determine the maximum load it can withstand. Therefore, swampy soil is considered the most difficult for building a house. Before determining the type of foundation, area and depth of its foundation, a thorough study of the geological situation of the site is necessary.

Geological soil studies

They are needed to determine basic soil indicators. These include:

volume of soil water;
soil type;
soil freezing level;
surface proximity of groundwater.

It is necessary to use a manual probe to sample soil. At least 4 wells need to be drilled on the site (in the corners of the future foundation). It is better to do this in the spring, when the soil is most saturated with moisture. Soil sampling provides the following information: composition, physical properties and thickness of the layers, their depth, changes in the soil over the past few years.

For wooden house you need to drill a well with a depth of 5 m or more, for brick or stone houses - 8–10 m. DIY foundation on swampy soil can be built if professional geologists assess the condition of the soil.

It is important to consider the depth of soil freezing. Insufficient foundation depth can lead to its destruction. Information obtained as a result of geotechnical research will help determine the type of foundation that will suit you.

Types of foundations for swampy soil

Work on arranging the foundation is the most labor-intensive and expensive stage of construction, which on swampy soil accounts for at least one third of the total cost estimate for building a house. Many years of research have shown that any foundation on swampy soil begins to collapse after a few years if it does not reach the depth of seasonal freezing. On the south side, where the soil moisture is greatest, it begins to “stick out” from the ground if done incorrectly.

Therefore, in order to foundation, erected in the swamp with your own hands, served for a long time make a drainage system. It makes it possible to drain excess water from the site. On swampy soils, three types of foundations are used. Let's consider these types.

Pile foundation

This type of foundation is considered the most suitable for swampy soil. It has the following advantages:

relatively low prices;
short construction time (can be built in 2 days);
construction can be carried out in any terrain;
work can be carried out in any weather;
increased durability and corrosion resistance;
increased strength and stability.

The use of piles of different heights makes it possible to smooth out uneven surfaces of the construction site. Its main part is the pile itself, which can be installed vertically into the ground or by making a slight slope. They are combined using a grillage (a concrete pad in a reinforcement frame).

In swampy areas, the following types of piles are used:

Screw piles in a metal shell. They are protected from corrosion with mastic or zinc coating and screwed into the ground using a special lever.

Reinforced concrete piles (driven into the ground with a hand piledriver).

Complex combined piles. They are placed in a casing pipe, which is removed after the piles are installed and the site is concreted.

Slab foundation

Reliable, but one of the most expensive types. It can withstand sudden temperature changes and heavy loads. The uniform distribution of the weight of the building over the entire area of the foundation does not allow it to sag, and the sand and gravel cushion located underneath allows groundwater to pass through without harming the foundation.

The construction technology is as follows:

A shallow pit is dug (up to about 1 meter deep).
It must be drained using drainage or using pumps (if there is a large amount of moisture).
Layers of sand and gravel are laid at the bottom of the pit, which are carefully compacted and covered with several layers of roofing material.
To pour concrete, formwork is made and a reinforcing frame of at least 12 mm is constructed.
The prepared area is evenly poured with concrete mortar and the slab is allowed to dry for several days. The formwork is dismantled.

You need to fill it in one go. They erect it on top strip foundation. Such a foundation can be made on your own, it is durable, when shrinking it protects the walls from cracks, and allows you to build a basement floor.

Shallow strip foundation

This is the cheapest foundation, but is only suitable for light buildings made of wooden beams and metal frames. It needs a good drainage system, because it is laid above the freezing point of the soil. They make it only monolithic, which allows shallow foundation due to its own rigidity, it resists soil heaving, evenly rising and falling along with the soil. He also needs a good sand “cushion” and insulation of the foundation base.

Nowadays, lay DIY foundation in marshy areas and building a house using modern technologies is not difficult. The main thing is an accurate calculation and a great desire, the rest is a matter of technique. Go for it, you can succeed.

Example with specialist comments (video)

Building a foundation is always associated with difficulties and serious financial costs. In some cases, home owners pay up to a quarter of the cost of the entire house construction for the foundation. And yet, you should never skimp on the foundation. Still, it bears the load from the entire structure. So any attempt to save on quality can lead to the most dire consequences.

Example of a finished monolithic foundation

However, in some cases, building a foundation causes even more problems than usual. Of course, we are talking about a foundation on swampy soil. This soil has a number of disadvantages. Firstly, this is a low load-bearing capacity - under significant loads, the soil simply gives way and the structure fails.

Secondly, there are seasonal fluctuations in ground level. This most often happens in the spring, when due to the melting of large amounts of snow, the groundwater level rises significantly.
In this regard, special requirements are imposed on the foundation in swamps. Not everyone can answer them.

It is a number of soil imperfections that make many people think seriously - what kind of foundation in a swampy area will best solve all the problems? After all, if the foundation was chosen incorrectly, after the ground level changes, the building may simply be destroyed.

An example of a monolithic foundation in a swampy area

In addition, after a few years, the building may simply begin to sink underground from its own gravity. Therefore, solving this problem should be approached as seriously and responsibly as possible.

Fortunately, today there are several options for solving this problem. Yes, you can decide for yourself which swamp foundation best suits your requirements and financial capabilities.

. This is an excellent solution if you need to complete the foundation in the shortest possible time. The main elements are piles - reinforced concrete or bored. Using special equipment, they are laid to a great depth - most often about 10-12 meters, but in areas with particularly difficult types of soil this depth can reach 20 and even 25 meters! Having gone to such a depth, the pile simply pierces the marshy layer of soil, resting on a solid foundation.
Pile foundation installation diagram
This makes the foundation and the entire structure of the house completely immune to seasonal fluctuations in soil level - the base acts as a support for the piles, the level of which does not change depending on the season or precipitation. It is important that all the work can be completed in two to three days. The installation cost is relatively low. Such a foundation can be installed both in summer and winter. Pile foundations in swamps have proven themselves to be excellent - reliable, durable and unpretentious, they have collected thousands of positive reviews from different parts of our country.
. The most expensive and difficult to manufacture. And yet, in the northern, swampy regions of our country, it is monolithic or most often used in the construction of private and multi-storey buildings. It consists of one huge, monolithic slab, buried to the level of soil freezing.
One of the options for a monolithic foundation
Even if the soil around you is very heaving, this in no way affects the reliability and safety of your foundation. The large weight of the slab (tens of tons!) eliminates the possibility of raising the foundation, which could lead to the destruction of the house. High strength allows a monolithic foundation to withstand enormous loads of compression, bending and tension without harm. Therefore, it is most often used during construction in marshy areas of our country, despite its high cost.
Shallow foundation. It occupies a niche between pile and monolithic foundations, both in terms of cost and construction time. Such a foundation in the swamp has also proven itself well.
Schematic diagram of a shallow foundation
However, it is worth considering that a shallow foundation is only suitable for - or. The fact is that the relatively small thickness of the foundation does not allow it to withstand significant compressive loads. At the same time, it perfectly resists loads from soil heaving. Since it is also monolithic, under heavy loads from the soil, it simply rises or falls slightly, like the entire house built on it. This, combined with low cost and speed of production, makes this type of foundation quite popular in swamps.

As you can see, people who decide to build a house even on problematic, swampy soil have quite a large choice. However, some of them do not want to spend extra money, preferring to build a foundation in the swamp with their own hands. Is it possible?

Which foundation is easier to build with your own hands?

Many of our compatriots prefer to carry out construction of any complexity with their own hands. First of all, because it makes it possible to save a lot of money. Of course, cases where they need to build a foundation in a swamp are no exception. So it will be useful to consider the possibility of building different types of foundations on your own.

First, let's look at the pile foundation. Alas, it is almost impossible to build it on your own, without the involvement of specialists. The fact is that only specialists have information about the thickness of the marshy layer in a certain area. In addition, they have heavy equipment at their disposal, which allows them to easily and quickly screw in piles to a depth of 10-20 meters.

Therefore, you should not even try to cope with this work yourself. Fortunately, this does not apply to monolithic and shallow foundations. In this case, the work can easily be done on your own, which will reduce construction costs several times. And even though you will need to rent a concrete mixer and, possibly, use the services of a bulldozer, the savings will be quite significant.

Construction of a monolithic foundation yourself

So you decided to build monolithic foundation. Where does it all begin?
Of course, from markings on the ground. For construction, it is best to choose the second half of summer - at this time the groundwater level is close to the minimum, rains are relatively rare, and warm air will allow the concrete to harden in the shortest possible time, without the use of special construction additives, which are quite expensive.

You can start building a foundation only when you already have finished project Houses.

In this case, you know exactly what the dimensions of the building will be and, accordingly, the dimensions of the foundation. It is desirable that the foundation protrudes beyond the perimeter of the house on all sides by 30-50 centimeters.
Using pegs and a nylon cord, you need to mark the specific place where the foundation will be located.

This is how the area for the foundation is marked

Now you need to remove the soil to a depth of 1-1.5 meters. The specific level of the foundation depends on the depth of soil freezing; this indicator can be obtained from any construction company.

Of course, when carrying out excavation work, many tens of cubic meters of earth will have to be removed. It is simply impossible to carry out such a volume of work manually with a shovel. Therefore, a smart move would be to rent an excavator and truck to remove all or part of the soil. Yes, you will have to pay a considerable amount. But you will save several weeks of continuous work.

The bottom of the resulting pit must be filled with crushed stone and distributed evenly. The thickness of the crushed stone layer should be 20-30 centimeters. After this comes the same layer of sand, which is also carefully distributed and compacted.

This stage should never be skipped.

The sand-crushed stone cushion allows you to solve several problems at once:

uniform distribution of the load from the foundation and the house over the load-bearing soil;
reduction of heaving effect in winter time of the year;
rapid removal of moisture after precipitation or melting snow from the foundation.

When the sand-crushed stone cushion is ready, it is necessary to lay reliable waterproofing. Roofing material is best suited for this. Yes, it is significantly more expensive than regular construction polyethylene. But it is more durable and efficient, and is also able to withstand significant tensile loads without tearing.

Sheets of roofing felt should not only cover the entire bottom of the pit, but also the walls to a height of at least 30-50 centimeters. The purpose of waterproofing in this case is twofold. On the one hand, the roofing material layer does not allow groundwater to come into contact with the concrete before it gains sufficient strength.

On the other hand, the possibility that “concrete milk” will be absorbed into the soil is excluded, as a result of which the strength of the monolithic foundation will be reduced.

The next stage is preparing the frame from reinforcement. To do this you will need fittings and binding wire or a welding machine. A frame of appropriate dimensions is constructed from reinforcement - it must cover the entire volume of the future foundation, thereby allowing the concrete to withstand significant bending and tensile loads.

Installation of the frame can be done manually, but in this case the work will take quite a lot of time.

Therefore, it is better to use a special knitting gun or welding machine - you will save at least one working day.

When creating a frame, take into account the fact that the reinforcement should be not only at the bottom of the foundation, but also at the top. The walls of the pit need to be covered with formwork - ordinary thin tin or plywood will do.

An example of formwork installation for a monolithic foundation

The main thing is to ensure reliable insulation liquid concrete from the ground from which it can draw water.
After this it is the turn of concrete. It is best to use concrete grade M400 or M500 for this. Yes, you will have to overpay at least several thousand rubles. But you will be sure that the foundation will be able to withstand enormous loads without the slightest harm to itself and, accordingly, to the house that will be built on it.

It is worth remembering that to pour the foundation you will need tens of tons of concrete. So, it makes sense to spend money and rent a concrete mixer. In this case, you can get a large amount of concrete in a short time. You should not pour concrete in several stages when the bottom layer has already set - the foundation will not turn out to be monolithic, and even small cracks in its structure will lead to its specifications will decrease significantly.

When the pit is filled with concrete, it must be compacted using special equipment - constant vibration allows you to fill any cracks with concrete and get rid of air bubbles in the foundation structure. Such bubbles can significantly reduce the strength of concrete.

After compacting the concrete, you need to leave it for three to four weeks so that it sets and gains sufficient strength. Setting times depend on many factors - air humidity, ambient temperature, foundation thickness and others.

Be that as it may, after a month you will receive a monolithic foundation that can easily serve you for many decades, withstanding any type of load and without losing its original strength.

That's all. Now you not only know which foundation is best suited for building houses in marshy areas, but also, if necessary, you can do all the required work yourself.

Never drying out swampy soil with moisture-loving vegetation that can be systematically moistened is not the most favorable place to build a house frame. The close location of groundwater creates seasonal fluctuations in soil, especially during spring warming. Modern construction technologies can solve the problem of how to organize a foundation in a swamp so that it can withstand the load of a house.

Soil analysis

What does swampy land represent? This is an area with a porous structure, which is 90% water. The remaining percentage is formed by chaotically located particles of minerals - peat, sand, clay. The unsystematic order of occurrence of rocks does not allow calculating the load on the soil.
Soil studies on the site will help identify the following characteristics of the area:

type of soil mass;
groundwater volume;
freezing depth;
distance of the aquifer from the surface.

The data obtained make it possible to determine the physical properties of the layers, their thickness and depth, and to characterize changes in the soil over the past few years. Based on geological expertise, you can choose which foundation to build in marshy areas.

How to explore the soil yourself?

It is not advisable for summer residents to delve into the details of geodetic surveys. Private developers need to take a number of simple measures:

selection of earthen material from four wells. The drilling depth is 5 m for wooden structures, 8 m for large stone buildings. It is better to probe the surface in the spring, when it contains the maximum amount of moisture.
Mechanical analysis is carried out by taking a small piece of earth. It rolls out in your hands and bends into a ring. A disintegrated element indicates sandstone, an unstable element indicates loam, a dense element indicates clay;
inspection of vegetation. On overly humidified marshy soils wild rosemary, blueberry, sedge, cloudberry, horsetail and other crops are present.

Research and determination of soil type include determining changes in groundwater level.

When does the groundwater level change in a swamp?

The volume of groundwater varies throughout the year. During the thaw period, their number increases significantly. The lowest groundwater level was recorded in winter. High aquifer imposes restrictions on building a frame in a swampy area. A moisture concentration of 2 meters or less poses a threat of flooding of trenches, pits, and the appearance of mold in the house or basement. A clear operating algorithm will help minimize the impact of springs on the life of the foundation.

Pile frame

A base designed for wetlands. Supporting elements are piles that are driven into the soil. A pile foundation in a swamp allows you to solve the problem of heaving, instability of the top layer of the earth, and allows you to smooth out the unevenness and slope of the territory.
Advantages of the structure:

low-cost, non-labor-intensive process (in 2 days you can build a supporting structure);
mounting the frame reduces the amount of earthwork: garbage removal, digging a pit, concreting;
choice building material for piles: wood, steel, reinforced concrete;
increased strength, long service life.

It is rational to use a pile foundation in swampy, unstable terrain with a high groundwater level. There are several limitations to consider when choosing a support structure:

weak bearing capacity in horizontally moving soil;
additional financial costs for the arrangement of the basement (filling voids).

The average depth of a well pit is 10-15 m. To mount a pile frame at a high groundwater level, use pillars at least 25 m long. The piles must be driven in until they fit tightly to the ground.

Work algorithm for constructing a foundation on piles

Performance construction work acceptable at any time of the year.

We treat the tongues with an antiseptic to prevent the development of corrosion.
We plunge the piles into the ground: we screw in the driven ones, and for the screw ones we use a special lever.
Cut off the excess protruding part.
We fill hollow pipes with cement.
Using an electric welding machine, we mount the support platforms on the cut parts of the piles.
We treat the surface with a waterproofing solution.
We connect the structure along the heads with a horizontal grillage.

High speed of construction and resistance to soil vibrations make it possible to increase the service life of the structure.

Slab foundation

The structure is widely used for the construction of a monolithic stone building. Concrete slabs are resistant to temperature changes and loads.
Problem high level groundwater is solved using a sand-gravel cushion located at the base of a monolithic slab, buried to the level of soil freezing. Rocks allow spring flows below their location, which prevents deformation. The sequence of technological steps will allow you to create a solid slab foundation in the swamp.

We prepare the wetland, clear it of vegetation and debris.
We drill holes in the corners of the future structure.
We drain the trench. For groundwater levels up to 2 meters from the surface, use pumps; from 2 meters and below, limit yourself to the drainage system.
We will strengthen the bottom of the pit with an embankment of sand and gravel. This will protect the foundation from the effects of groundwater. We form roofing felt flooring on top.
We make formwork from lumber.
We install reinforcement made of metal rods along the entire perimeter of the form-building structure.
We fill the trenches with concrete mixture in several approaches. The thickness of each layer should not exceed 0.2 m.
Dismantle the concrete form after the solution has dried (it will take several days).
We treat the vertical and horizontal surfaces of the frame with waterproofing mastic.

A foundation in a swamp made of monolithic slabs is an expensive type of construction. Changes in soil heaving will not affect the reliability and strength of the frame. Therefore, slab foundations are mainly used for marshy areas.

Tape base

A shallow foundation for a house is suitable for the construction of small frame structures made of wood. The peculiarity of the type of supporting structure is that the depth of the masonry is higher than the freezing level of the soil. When arranging the feed, you need to take into account a number of nuances:

The role of the drainage system is performed by a cushion of sand and gravel.
When the soil heaves, the reinforced frame rises slightly, but the use of monolithic technology allows it to maintain its shape and prevent the appearance of cracks.
At the design stage, soil characteristics should be determined. This will allow you to calculate the effect of loads on the future construction and determine the safety margin.
The sequence and technique of performing the work of arranging a foundation, which is located in a swampy area and is relevant in case of high groundwater loss, is identical to laying a deep-depth tape - digging a pit, forming a cushion, constructing formwork, reinforcement and layer-by-layer pouring of cement mortar.
It is advisable to install a channel for water drainage along the entire perimeter of the foundation at a distance of 1.5 - 3.00 m.

Ease of installation and low cost make the tape popular as a foundation on marshy soil.
Dampness and moisture have a destructive effect on the frame. It is difficult to predict how soil density will change over time. To avoid the effects of swelling of the ground, use waterproofing systems. When choosing the type of foundation that will be located in soft, swampy terrain, be guided by the climatic conditions of the area, the type of structure and the budget.