Shallow foundations, their types and conditions of use, heated

What is a shallow foundation? Varieties

Construction processes begin with the selection and arrangement of the foundation. The type is selected at the design stage, taking into account the characteristics of the soil and climate in the region. Shallow foundations, the pit depth of which is no more than 1-2 m, are popular. Their types include several options. Below are the nuances and recommendations for the optimal choice for the individual platform construction process.

Conditions for laying shallow foundations

In order for the foundation to serve as a reliable structure for the entire facility, its type is calculated based on the following characteristics:

1. Level of freezing of the soil layer.
2. Groundwater occurrence.
3. Soil type - composition and behavior.

• The depth of the foundation base is determined by how severe the climate is in the area where construction is taking place. This measure will allow the selected option not to crack or deform at sub-zero temperatures.

The cold regions of the country cannot have high-quality residential structures placed on shallow platforms. The thesis is relevant when purchasing finished housing.

• The occurrence of groundwater is a decisive factor for choosing a foundation. At a level close to the surface of the earth, the use of great depth for the foundation is fraught with flooding of the basement floor and, as a consequence, destruction of the concrete. In this case, reducing the height of the structure is a necessary action.
• The type of soil and its “capriciousness” are important conditions for determining whether a shallow foundation is laid or a more solid one. Heaving and floating soils should not cause destruction or severe shrinkage of the house. It is also necessary to pay attention to the composition of the soil - sandstones or peat areas will require compliance with the conditions for them. Neglecting such characteristics will have an adverse effect on the strength of the residential structure.

The base options described below best conform to these characteristics. You can find out the relevant local data in construction reference books for a specific geography, or outsource the construction process to turnkey companies - a specialist visiting the site will assess the condition of the soil. A description of shallow foundations, as well as their types and conditions of use, is below.

Soil heaving: features and methods of combating

To get an answer to the question of how to properly make a foundation on heaving soil, you need to understand the nature of the process provided and its specifics.

In areas with a high groundwater level, the ground is in a very wet state and thus begins to increase in size closer to cold weather.

When constructing a foundation on heaving soil, you need to monitor the depth of the soil.

If you go deeper just below the freezing point, the fragile layers will exert pressure directed tangentially to the surface of the earth. She will begin to rise.

An equally important component is the area of ​​interaction with the ground: the larger, the worse.

In the future, the soil will sag under the influence of constantly changing vertical loads. And thus, this process is observed irregularly.

As a result, the house begins to weaken, and the foundation cracks and, of course, fails.

A special SNiP for foundations that are built on heaving surfaces has been created under the number 50-101-2004; the law was adopted back in 2005. It is recommended that everyone familiarize themselves with it before starting work.

Regardless of the type, it is advisable to construct a foundation on heaving soils as an expanded monolith at the bottom.

In order to reduce heaving, a special heating system is created in the basement, and, of course, the foundation of the house itself is insulated.

Another way to combat ground heaving is to replace the soil.

As a rule, unstable soils under future construction are removed, and instead they are filled with crushed stone along with sand. An important drawback is the high price of the work provided.

The most common type is a shallow foundation on heaving soils.

A small backfill depth provides the opportunity to remove tangential pressure by reducing the size of the interaction.

However, for the chosen method to be effective, it is necessary to create a special cushion from a mixture that, in turn, is not subject to heaving (sand, crushed stone of a standard fraction).

It is important that the mixture is poured from the outside of the foundation over the entire area.

If you lay the foundation significantly below the freezing point, there is a chance that you will compensate for heaving.

Read also: Slab foundation pros and cons, video

However, it is not profitable to equip the belt using this method, since construction will require quite a lot of costs. Increasingly, columnar foundations are being built on heaving soil.

But difficult calculations must be made to distribute the pressure evenly. It is necessary to use different brands of bud and, preferably, a reinforced reinforcement frame.

It is difficult to say which of all those available is the best foundation for heaving soils - each has its own characteristics and positive aspects.

In addition, the level of heaving in different areas can vary significantly, which affects the decision on the choice of foundation type.

Types of bases

All types of platforms can be arranged at a short distance from the ground surface. These include:

There is also a separate type of foundation - pile, but it is installed below 3 m, and it is rightfully considered a deep-laying option.

1. Stove. The most reliable design of all types presented. It is a reinforced concrete slab reinforced over the entire area. Such a platform is not threatened by the climatic and geodetic conditions of the area. In addition, a building on such a foundation practically does not shrink. The disadvantages include the high cost of the foundation - up to 50% of the entire construction. The price includes the necessary participation of specialized equipment and the amount of fittings.

2. Tape. A popular option in various constructions. Available in two designs:

• prefabricated monolith with the release of fittings;
• block foundation with reinforcing belts - upper and lower.

Requires several stages of preparation before pouring, namely:

• digging a ditch with precise parameters for load-bearing walls;
• installation of crushed stone and sand cushions that serve as drainage;
• reinforcement.

To get a shallow, frost-resistant foundation like a tape, it will have to be insulated with styrene on the internal walls. The basement floor will not do without additional padding.

The advantages of this type include the possibility of self-installation without hiring outside forces and reduced cost when compared with a stove. In addition, it is possible to install houses of any design and material on the tape.

3. Columnar bases. Recommended for small one-story, mostly wooden buildings. They are pits with reinforced concrete rings, filled with mortar in all corners of the future structure and its load-bearing units in increments of no more than 2 m. They can be made of brick or asbestos concrete by factory molding with the release of reinforcement. After installation, the pillars are cut to level, after which a grillage is installed on them.

Shallow columnar foundations are unpopular due to their disadvantages:

• are too dependent on the behavior of the soil - the level after shrinkage may change;
• the bottom of a residential building becomes accessible to all winds;
• limitation in construction materials - a lightweight option is selected;
• you will have to forget about the ground floor or basement as useful space.

Having properly assessed your own financial and physical capabilities, you can choose a platform suitable for your own construction or give this task to foundation specialists in a particular region.

Selecting the depth and installing a sand and gravel cushion for the foundation

Turnkey house design pre-determines the type of foundation. Before designing a specific option, three parameters are analyzed:

1. The design of the finished house - area and material of manufacture. The definition is needed to find the maximum load on the platform surface - kg/m2.
2. Climatic conditions of the area. At severe subzero temperatures, there is reason to think about a reliable recess to avoid damage to the concrete.
3. Soil composition and moisture level. Capricious soils can cause shrinkage and defects in the finished structure.

For example, the project includes a wooden or cinder block house with an area of ​​157 m2. The area has clayey soil of medium movement. The average winter temperature is around -15-20⁰. The waters lie below 2 m. Thus, the best foundation would be a reinforced strip option up to 1 m below the basement floor + drainage.

Different foundations can be shallow or deep, but none of them can do without constructing a so-called cushion of sand and/or gravel. It serves as protection against harmful waste liquids located near industrial enterprises that can interact with the base and create destructive processes regarding the chemical composition of concrete. Each layer protecting the platform from moisture is carefully compacted, spilled with water and calculated to a height of at least 15 cm. After which the foundation is reinforced and poured. The drainage must contain coarse sand, crushed stone or expanded clay. All three components can be used with a total height of up to 30 cm.

The correct choice and arrangement of a platform for private or other types of construction is the key to long-lasting and comfortable living.

When laying the foundation to great depth is necessary

The need to arrange deep foundations arises in the following cases:

• When carrying out construction work in difficult ground conditions;

If the construction site is dominated by loose, low-density soils, building a house on such soil, especially if it is a heavy brick structure, is strictly contraindicated. The weight of the building, exerting a vertical indentation load on the foundation, will cause it to shrink.

Rice. : The result of uneven shrinkage of the foundation
Shrinkage can be uniform or uneven. With uniform shrinkage of the building, the house can sink 10-20 centimeters deep into the soil; with uneven shrinkage, only one of its sides will sink, but as a result of such deformation, cracking of the walls, plinth and foundation strip will occur, curvature of door and window openings, which will lead to an emergency condition Houses.

Expert advice! When constructing deep foundations on problematic soils, the upper low-density layer of soil is opened, and the foundation rests on a deep layer of soil, which has a much higher density and load-bearing capacity, which reduces the risk of foundation shrinkage to a minimum.

• When building houses on heaving soil;

Soil heaving is the tendency of soil to change its volume as a result of freezing groundwater. Heaving forces begin to affect the foundation of the house in the cold season, when the soil freezes and the moisture with which it is saturated turns into ice.

When moisture transitions from a liquid to a solid state, its volume increases by 5-10% of the original, which is due to the different nominal mass of one cubic meter of water and ice.

The increased volume of the soil begins to expand in all directions. Since the lower layers of soil have a high density and mechanical load has no effect on them, heaving soil has only one direction of movement - upward. It puts pressure on the foundation located in the ground, causing it to be pushed out and deformed.

Rice. : Impact of vertical and tangential heaving forces on the foundation

Expert advice! When designing deep foundations, the main factor in their calculation is the depth of soil freezing - if the foundation is laid below this depth, it is not exposed to vertical heaving forces (pressing on the supporting base of the foundation), and the remaining tangential impact is effectively leveled by sprinkling the foundation walls with non-heaving materials ( sand and gravel).

Rice. : Types of backfilling of different types of strip foundations

• When constructing buildings with a basement.

Deeply laid foundation strips not only support the house, but can also be used as walls for the basement or basement. The construction of a pitch, when arranging a deep foundation, does not greatly increase the cost estimate of the project, since additional costs are associated only with digging a pit for the basement and concreting its floor.

Main types of shallow foundation

Many owners of country houses want to save their money. This is why many people use shallow foundations.

Scheme of the main shallow foundations.

Compared to a deep foundation, the use of this type of foundation is much cheaper.

In addition, the risk of destruction of the entire building is minimized. Today, such foundations have four main types: strip, columnar, monolithic and slab. Each of them has its own characteristic features, construction conditions and a specific area of ​​application. The conditions for choosing each type must be justified by a special calculation; the structure of each foundation is clearly regulated.

Where is a deep foundation used?

The excellent load-bearing characteristics of the foundation have made it the de facto main type for high-rise buildings made of brick and precast concrete. At the same time, when carrying out survey work, it is not advisable to focus on deep foundations in places with high groundwater levels. In such cases, all efforts may come to naught; there will be no solid support on the ground.

Deep reinforced concrete foundations are expensive structures, the construction of which requires quite a lot of financial and time costs.

It is rational to build deep foundations in soil conditions in which the depth of soil freezing does not exceed 2.5 meters and the groundwater level is less than the GPG.

Expert advice! When laying foundations to a depth of more than 2-2.5 meters, the labor intensity and cost of excavation work associated with digging trenches and pits, and the amount of required consumables, sharply increases.

In such cases, it would be more rational to use pile foundations based on bored or driven reinforced concrete piles, the bearing capacity of which will be no less, and the final cost will be an order of magnitude lower.

Strip foundation type

Shallow strip foundation slab is rightfully considered the most popular in dacha construction. This type of device can be used for:

Scheme of a shallow strip foundation.

• wooden buildings;
• houses that have heavy stone walls, if the construction conditions are followed.

If you plan to carry out measures to insulate the soil, then installation on any type of foundation is allowed. A strip foundation is the following device: a continuous strip of concrete, which must be evenly loaded by the walls of the entire structure. The types of such construction can be different:

• monolithic with two reinforcing belts;
• prefabricated monolithic with several reinforcement outlets;
• from reinforced concrete blocks with upper and lower reinforcing chords;
• made of reinforced concrete blocks, but with an upper reinforcement belt.

Shallow strip foundations have a number of undeniable advantages:

• tangible savings in money. If we consider them with foundations whose depth is much greater, then construction will cost 2.5 times less;
• you will save labor resources. The construction of such a belt involves a relatively small scope of work. First of all, savings arise due to the smaller volume of excavation work and the ease of creating the necessary formwork;
• you will have the opportunity to build a small basement.

It has been proven by practice and special calculations that the installation depth of a strip foundation can correspond to either the depth of soil freezing or the depth of the plant layer. Often in specialized literature you can find a figure of 50 cm. This depth is the most dangerous, because this is where the main forces of frost heaving are concentrated.

Pile-grillage foundation tise

It is an ideal foundation solution for wooden and combined houses, and is also suitable for the construction of a stone house, with minor changes (in particular, increasing the diameter of the piles, the cross-section of the grillage itself, reducing the pitch of the piles, etc.). Such a foundation is especially relevant in areas with height differences. It is optimal for clay soils and hard-plastic loams, and also, due to the expansion of the heel from below, is also suitable for less dense loams.

Such a foundation perfectly distributes and withstands the load of the house. The voltage from the house is collected through monolithic reinforced concrete. grillage and is transferred to piles, the base of which is below the freezing level and rests on dense soil. The grillage, in turn, is located above the ground and surface heaving of the soil, which appears as a result of freezing of the upper soil layers, does not cause damage to the foundation.

Specialists will measure the height difference and clearly demonstrate to you which angle of the future foundation will rise to what height above ground level.

The installation technology of this type of foundation is characterized by the almost complete absence of excavation work, which reduces construction time and, accordingly, the total cost. Holes for the piles are made using a gas drill, into which asbestos-cement pipes 600-1000 mm long are mounted (depending on the height difference). The pipes serve as a kind of “conductor” of concrete between the grillage and the pile itself. The so-called heel (expansion from below) is made with a special drill called bur-tise, which opens up like a plow. Refinement is already done manually. Next, the formwork is installed and the reinforcement is knitted.

Columnar base

The second most popular can be considered a shallow columnar foundation. It can be used:

Scheme of a shallow columnar foundation: a - for wooden houses; b - for brick houses; 1 - walls made of timber; 2 - load-bearing lintels or foundation beam; 3 – reinforced concrete slab 90×90 cm; 4 - sand-gravel mixture; 5 - reinforced concrete ring KS 7-9.

• for brick houses;
• wooden houses.

A columnar foundation is a formation of pillars that connect the site and the house. For greater stability and smoothing out possible changes that may occur in the soil over time, certain conditions must be observed: a gap of 200-250 mm is left between the pillars.

To create this type of foundation you need:

• specially drill a pit, the depth of which must be at least one meter;
• then place rings with a diameter of 90 cm into it, which will later be compacted with sand;
• the rings must be covered with concrete slabs up to 10 cm thick;
• The grillage of the structure itself is mounted on the slabs.

Slab foundation

Scheme of a shallow slab foundation.

The third most popular is considered to be a shallow slab foundation. To build this type of foundation, it is necessary to pour a reinforced concrete slab 20-30 cm thick under the entire area of ​​the future structure. The walls of the future house will subsequently be built precisely on this foundation.

The slab type structure of such a foundation is similar to a strip foundation. The main difference of the design is that the slab has rigid reinforcement along the entire plane, which is capable of absorbing any loads due to possible ground movement. To put it in more understandable terms, the house floats on a raft, and it is this effect that is ensured by the reinforced concrete slab.

If we talk about the main advantages of this type of foundation, the depth of which is relatively small, then first of all it is worth noting:

• reduction in concrete consumption by 25-30% compared to deep foundations;
• the price is two times lower, which makes it possible to save a lot of money;
• If this slab is selected, you will get maximum efficiency in using the entire foundation.

Cost per linear meter

The price of construction consists of many factors, so no developer will decide to pre-determine the cost. You can focus on the average cost per linear meter of a slab foundation, added to the indicator for a pile and grillage foundation:

Monolithic base type

A shallow monolithic foundation is ideal for:

• houses with a light frame;
• light structures.

This foundation structure differs from all others in that all sections are specially combined into one rigid frame, which allows the resulting loads to be evenly transferred to the entire foundation as a whole. That is, the action of the so-called heaving forces is redistributed over the entire area of ​​the sole, which can significantly reduce their negative impact.

A shallow monolithic foundation can be safely used on any type of soil; the depth of the foundation allows this to be done. The only exceptions are those areas that have a slope. Now you will also not have problems with arranging the plinth, since the rigid frame will perform all its main functions, the depth allows this to be done.

The construction of a foundation of this type is characterized by significant material costs and labor costs, most of which are spent on preparatory work. In addition, the depth of the foundation is slightly greater than that of other types of shallow foundations. But among the advantages of this type, it is worth highlighting the increased reliability.

When and which one is better to choose?

A slab on piles is chosen for the construction of multi-storey buildings and industrial facilities, when the rigidity and reliability of the load-bearing structure on unstable soils is important. Such a structure will differ in its resistance to vertical and horizontal loads arising in the ground.

The scope of application of a pile-grillage foundation with a slab is wider . The design features of the system allow the foundation to be used in the following cases:

• the structure has many heavy floors and partitions, which necessitates the need for even distribution of weight on the base;
• the building rests on subsiding and waterlogged soils;
• underground sources on the site are located close to the surface;
• construction is taking place in an area of ​​high seismic activity.

Features of foundation design for severe geological properties of the site are described in SP 24.13330.2011.

Basic concept

The main problem of complex soils is heaving during freezing, which causes them to significantly increase in volume. This factor leads to the gradual destruction of the foundation and the entire building. This can be avoided by balancing the buoyant force by increasing the load on the foundation, that is, the weight of the building, but private houses and summer cottages are lightweight buildings, so deep types of foundations, including pile ones, are not suitable here. The solution to the problem is a shallow foundation.

The very name of the structure already makes it clear what shallow foundations (FMF) are. Its depth is from 40 to 50 cm, which significantly reduces the impact of soil during heaving on the lateral area of ​​the walls of the building.

The minimum depth of the foundation helps reduce financial costs and time for its installation by at least 2 times.

In this case, significantly less concrete, crushed stone or sand is required to make the substrate and material for constructing the formwork. The components of the design are:

• the edge is the upper part that takes the load from the house;
• lower part transmitting load;
• side parts, that is, walls.

Such foundations are not built directly on the ground; they are mounted on a bed of sand, fine-grained crushed stone or slag, previously compacted with high quality.

Approximate diagram of laying a sand cushion

Preparation and design

Before designing, the characteristics of the site are analyzed, namely:

• type and physical and mechanical properties of soil;
• degree of heaving of land masses;
• depth of seasonal soil freezing;
• risks of flooding, landslides, etc.

Calculations of design loads are carried out, including during the operation of the structure. Based on the data received:

1. 
   A decision is made on the advisability of using a pile-slab or pile-grillage foundation with a slab.

   Read also:  The height of the foundation above the ground for a one-story house made of foam blocks
2. Select building materials (grade of concrete, characteristics of reinforcement, etc.).
3. Determined with the geometric dimensions of the power elements.
4. Calculate the optimal depth of the supports.
5. Calculate risks regarding settlement and various deformations.

Design involves drawing up a drawing. The graphic document contains information:

• dimensions of the structure being built;
• cross sections of all power elements;
• dimensions of supports, slabs, grillage, blind areas, ledges;
• location of piles taking into account the pitch;
• elements of waterproofing and thermal insulation;
• reinforcement features;
• utility lines and more.

Attached to the graphic document:

1. Specifications of all structural elements.
2. Installation plan.
3. Table of permissible loads.
4. Notes regarding base features.

Drawings of pile-slab foundations:

Types of FMZ

Types of foundations are classified according to the method of laying:

• monolithic with reinforcement installed only on the slab part;
• columned;
• prefabricated using individual concrete blocks;
• prefabricated monolithic: concrete is poured into the spaces between the slabs.

They are also divided by type of materials:

• tree;
• stone;
• concrete;
• reinforced concrete.

What does a tape-type FMZ look like?

Strip foundation type

The most common types of shallow structures are strip foundations. The optimal basis for their construction is continental, that is, natural soil. Such a basis will become relevant for the further construction of a structure made of materials such as adobe, brick, small concrete blocks, and cinder block.

Shallow strip foundations are characterized by ease of construction and minimal work time. The structure also requires from several days to a month to “rest”.

The material used for their construction is:

The most labor-intensive option is made from rubble, where small stones are connected to each other using concrete mortar. For a rubble concrete base, formwork should be built, rubble and crushed bricks are laid in it and subsequently filled with concrete.

If necessary, the structure is reinforced from the inside to increase strength.

Stages of construction of a shallow strip foundation

Despite the simplicity of the construction of the FMZ, it requires the correct execution of all work. Otherwise, instead of eliminating the shortcomings of the powdery soil, it simply deforms from the weight of the building. The construction process involves the following actions:

1. Preparatory work, including cleaning and leveling the area.
2. Marking internal and external corners.
3. Digging a pit and leveling its bottom. If necessary, the foundation walls are additionally strengthened using the embedded or tongue-and-groove method.
4. Laying a pillow whose purpose is to level the bottom. To determine its material, it is advisable to do a soil analysis for the presence of groundwater.
5. Tamping the pillow.
6. Installation of wooden formwork. A layer of resin can be applied to its inner surface or a waterproofing material can be laid.
7. Installation of a frame made of reinforcement. It is made of rods with a cross-section of 1.2 cm, their joints are connected using clamps or by welding. The corners of the joints can be connected with metal rods to increase the strength of the structure. For a rubble or brick foundation, a backfill layer is used.
8. Pouring the formwork with concrete.

When pouring the formwork, concrete of a grade of at least 200 is used. To increase the strength of the foundation, layers 15-20 cm thick should be made in stages. Before pouring, the formwork must be wetted.

Features of the construction of a shallow slab foundation

A slab foundation is more reliable and durable than a strip foundation, which is why it is often used in construction on difficult soils with high water levels. The costs are more significant, but they are justified by the absence of the need to perform additional excavation work.

Construction of this type of foundation includes the following work:

1. Leveling the surface, marking the markings.
2. Removing the top layer of soil over the entire area of ​​the foundation. Where a denser layer lies, the bottom of the ditch is leveled and compacted.
3. When soil moisture is high, plastic pipes are laid at the bottom of the trench and covered with geotextile. Preventing freezing will eliminate the insulation of the foundation from all sides.
4. Installing a cushion under the slabs. Its thickness should be 15-20 cm. The material is sand or crushed stone, which is carefully compacted and watered during the laying process.
5. Laying waterproofing and expanded polystyrene or polystyrene foam on top of the pillow.
6. Installation of formwork, it is usually made of timber, the width of which will be equal to the thickness of the foundation.
7. Installation of two layers of rebar grating.
8. The formwork is filled with concrete grade no lower than 200. It is better to do this in several layers, pouring water over them to prevent rapid drying of the material and the appearance of cracks.

The main feature of the slab foundation is its solid, monolithic structure. This is a slab under the house. Its surface serves as a floor for the future structure, which completely eliminates the possibility of deformation of the base of the building.

Common mistakes and tips on how to avoid them

Installation of a slab-pile foundation is a complex and labor-intensive process, which is usually trusted to professional builders. At the same time , the customer needs to ensure that employees do not make typical mistakes:

1. 
   Refusal of an additional waterproofing layer when the foundation slab is the floor of the lower floor.
   To reduce heat loss, experts advise laying a layer of clay between the ground and the sand cushion, and a sheet of foam plastic directly under the slab.

2. Pouring the solution in several stages.
   The problem is related to the significant volume of concrete required for construction. When the solution is supplied in parts, it gradually begins to harden and as a result, seams are formed, reducing the strength and rigidity of the foundation. As a rule, concrete is fed simultaneously through special chutes, avoiding impacts. The solution is then vibrated to remove air and maximize compaction.
3. The use of heaters to speed up the hardening of concrete. As a result, the slab turns out to be heterogeneous in composition, and the design strength of the base is reduced.

Installation of a shallow columnar foundation

This type of base is suitable for bathhouses and small wooden houses, as well as structures made of light building materials, for example, summer houses made of plasterboard or chipboard. The main advantage of such a foundation is rapid construction and minimal construction costs. It includes the following steps:

1. Design and calculation of the foundation. Experts recommend conducting a laboratory analysis of the soil in order to determine the exact depth of the pillars depending on the depth of its freezing.
2. Calculation of the distance between pillars (for monolithic products this is 100-120 cm).
3. Performing markings.
4. Digging a hole around the perimeter of the foundation, its thickness should correspond to the cross-section of the pillars.
5. The pit is filled with crushed stone up to 20 cm thick, it is carefully compacted.
6. Implementation of a reinforced structure. First, rods are installed at the width of the foundation, then longitudinal parts are attached to them. The grating can be mounted either in the pit itself or in a separate area with subsequent immersion of the structure into the trench.
7. Pouring with concrete grade 250.
8. Making a box from long edged boards; it should not have a bottom.
9. attaching formwork to pre-erected reinforcement structures.
10. Filling the formwork with cement mortar of the same brand.
11. Making a fence and a bitumen layer that protects it from moisture.

For the most durable use of this type of foundation, you should adhere to a few simple rules:

• correct calculation of the foundation;
• the uniform load is not its total area and individual elements;
• selection of exclusively high-quality materials both when pouring the foundation and when constructing formwork;
• All work should be carried out in summer or early winter.

Columnar elements should stand from two weeks to a month until the concrete hardens completely.

In the video provided below, you can understand the basics of how FMP is performed: If you adhere to all the rules listed above, a shallow foundation will become a very economical and convenient option for creating the foundation for a private building. It should be used in private construction and in certain soil conditions.

Monolithic foundation slab

It is an ideal solution for the foundation of any house and in any soil. This is a relatively expensive and at the same time the most reliable type of foundation. This base is indispensable on weak and heterogeneous soils, quicksand and other “unreliable” soils. Also, a monolithic slab is used in the construction of basement and ground (in use) floors, when the top of the slab serves as the subfloor of such a tier.

The technology for pouring a monolithic foundation slab is quite complex. The technical department relied here on the developments of the Research, Design and Survey and Design and Technological Institute of Foundations and Underground Structures (NIIOSP) named after. N.M. Gersevanov (FSUE Scientific Research Center "Construction"), as well as on the developments of FSUE "Fundamentproekt" and Moscow State University. M.V. Lomonosov (Faculty of Geology) under the guidance of Doctor of Technical Sciences L.N. Khrustaleva. At the first stage, a pit is developed mechanically - this is one shift of work for an excavator, and when removing soil and a dump truck - several shifts. Then half a shift is spent on manually refining the soil. Geotextiles are spread on a leveled pit, onto which first crushed stone is compacted layer by layer, and then sand. The compacted sand is used to create a built-up waterproofing layer in two layers using hydroglass insulation. Next, depending on the type of soil, you can install a layer of foundation insulation. The final stages are installation of formwork and tying of reinforcement. And don’t forget about the embedded holes for future communications. At the same time, it is recommended to create a drainage system around the foundation.

Regarding the price of this type of foundation. Let’s take an average house of 10x10 m, in addition to excavation work using machinery and manually, layer-by-layer compaction requires 5 KAMAZ trucks of crushed stone and sand, 5 rolls of geotextiles, 26 hydroglass insulation, 33 cubes of concrete, almost a ton of reinforcement, formwork and other consumables. You understand, this costs money, but it will give you confidence in the reliability of the foundation of your home!