Foundation from asbestos pipes. How to make a columnar foundation from asbestos pipes with your own hands? Scope and features of the foundation of asbestos-cement pipes

The foundation of asbestos-cement pipes is an excellent alternative to a monolithic slab or strip concrete foundation in the construction of relatively light structures. By building it, you can save a significant amount of money. This type of foundation is almost indispensable in the construction of light frame houses or outbuildings.

The only disadvantage of this type of foundation is that it is problematic to build inhabited basements or basements inside it. However, if the design of your building does not provide for a basement or basement, then instead of a rather expensive monolithic strip foundation, you may well limit yourself to a bored foundation foundation constructed using asbestos-cement pipes.

All work on the construction of a bored foundation from asbestos-cement pipes on a personal plot can be done by hand. This construction is accessible even to people with minimal technological skills.

The difference between a bored foundation and a strip or slab foundation is that the supports for buildings are not mounted under the entire base of the building or under its perimeter and load-bearing walls - but only at key points. Such points are the corners of the structure and the junction of the internal load-bearing walls to the external ones.

The construction of a strip foundation provides for its deepening into the ground below the level of winter freezing of the soil. As a result, a large mass of concrete has to be used in the middle lane, which negatively affects the project budget. However, relatively light buildings can also withstand concrete pillars, which can be placed deep enough in the ground.

The foundation in the form of pillars can be constructed in two main ways.

The first way is to use ready-made piles. However, in private housing construction, this is of little use, since it requires the use of specialized equipment.

The second method is the manufacture of supports directly in the ground. In this case, the concrete solution is poured into the formwork created in the hole in the ground. Various structures can be used as formwork, such as traditional wooden panels.

Formwork for piles - photo

Asbestos-cement pipes are very popular as formwork for creating bored piles. They are relatively light, have excellent waterproofing and are quite durable, so they are ideal for the role of fixed formwork. Currently, the industry produces asbestos-cement pipes of various diameters, which will allow you to accurately select the pipe sizes necessary for the construction of your particular structure.

Please note that the diameter of asbestos-cement pipes is selected based on the weight of the future structure. By the way, you can calculate the weight based on the data in the table.

In addition, bored piles using asbestos-cement pipes can be used when building foundations on uneven areas, such as slopes. It is possible to build this type of foundation on soil with very high humidity, practically in swamps. The manufacture of such a foundation does not require the use of construction equipment and can be carried out even by one person for a long time, sequentially from support to support.

However, it is worth noting that before the construction of such a foundation, it is necessary to make a careful calculation of the structure. To do this, it is necessary to calculate the planned total weight of the structure, including the weight of building materials, the load of the room and the possible load from changing climatic conditions. After that, the maximum load on the concrete pillars is calculated. With a large weight of the building structure, it is necessary either to increase the number of concrete supports, or proceed to the design of a strip concrete base.

The process of building a foundation from asbestos-cement pipes

At the preparatory stage, we need to create a foundation project and make all the necessary calculations. When calculating the required number of supports, keep in mind that the maximum distance between the posts should not exceed 2.5 meters.
Then prepare the construction site, clear it of debris. It makes sense to remove the fertile soil layer and transfer it to another part of your site.
We are marking the future foundation. We carefully check the correct marking of the corners. To do this, we stretch the marking cord not only along the sides of the foundation, but also along its diagonals, achieving the creation of an ideal rectangle.
We carry out drilling of wells for supports. To do this, you can use both a regular garden drill and a TISE tool. When working on difficult soils, it makes sense to use the services of a drilling rig. The depth of drilling of wells should go beyond the level of soil freezing.
At the bottom of the drilled well, a sand cushion about 20 centimeters thick is placed. It is spilled with water and carefully compacted.
On especially weak soils, it is possible to create a concrete support at the bottom of the well, wider in diameter than an asbestos-cement pipe.
A layer of polyethylene can be laid at the bottom of the well so that moisture from the concrete solution does not go into the ground.
We lower the asbestos-cement pipe into the well, with the help of spacers we fix it in a vertical position, we check this with a building level.
On the ground, we assemble the inner metal frame of the support from reinforcing bars. It should have both horizontal and vertical power belts. We lower the assembled frame into the pipe. If you are planning the construction of a horizontal piping - a grillage, then the reinforcing rods from the pipe are brought out to connect them to the grillage reinforcement.
Pour concrete mortar into the pipe. After pouring a portion that raises a layer of concrete by 20-30 cm, it must be bayoneted or treated with a vibrating drill.
The space between the pipe and the walls of the well is filled with sand and compacted. During construction on heaving soils, the sand cushion between the well and the pipe should be at least 10 centimeters.
The upper part of the pipe is cut at the laser level, then the head and waterproofing are installed, or they begin to erect a horizontal grillage.

The foundation of asbestos-cement pipes - photo

conclusions

Thus, it is possible to create a fairly solid foundation for relatively light buildings, but not more than one floor high. Also, such a foundation will be an ideal solution for the construction of household or household buildings.

In contact with

In this article, we will consider a columnar foundation made of asbestos-cement pipes. They are also called a / c pipes or asbestos pipes. This type of fixed formwork is very popular due to its numerous advantages, which we will discuss in this article.

Advantages of a columnar foundation made of asbestos pipes

Formwork from asbestos-cement pipes together with poured concrete create a solid structure.
High strength, frost resistance.
Resistance to aggressive environments.
Unlike roofing formwork, they have high rigidity. No formwork deformation during concrete pouring.
They have a smooth outer surface.

Flaws

More expensive than roofing felt formwork, but this disadvantage pays off with a large list of advantages.

Composition and types of a / c pipes

Composition of a / c pipes: asbestos (15%) + Portland cement (85%) + water.

Varieties: Asbestos pipes are available in 2 types: pressure and non-pressure.
Non-pressure a/c pipes are designed to create networks of non-pressure sewerage, ventilation, etc., where the transported medium is supplied without pressure. They are labeled BNT.
Pressure a / c pipes are more durable and are used in conditions of high pressure (6-9 atm). VT marking.

Average prices for asbestos-cement pipes (St. Petersburg)

Non-pressure asbestos-cement pipes

	Length, mm	External diameter D, mm	Inner diameter d, mm	Weight, kg	Price, rub./pc.
A / c pipe BNT-100	3950	118	100	24	360
A / c pipe BNT-150	3950	161	141	37	580
A / c pipe BNT-200	3950	211	189	64	1210
A / c pipe BNT-200	5000	204	184	74	1310
A / c pipe BNT-250	5000	252	228	94	1780
A / c pipe BNT-300	5000	295	269	121	2560
A / c pipe BNT-400	5000	388	356	199	4000
A / c pipe BNT-500	5000	508	454	359	7600

Pressure asbestos-cement pipes

Asbestos-cement non-pressure pipe	Length, mm	External diameter D, mm	Inner diameter d, mm	Weight, kg	Price, rub./pc.
A/c pipe d 100 W-9	3950	122	100	45	760
A/c pipe d 150 W9	3950	168	141	67	1110
A/c pipe d 200 W-6	5000	224	200	123	1670
A / c pipe d 200 W-9	5000	224	196	142	2010
A/c pipe d 300 W-6	5000	324	292	199	3190
A / c pipe d 300 W-9	5000	324	286	217	3970
A/c pipe d 400 W-6	5000	427	385	333	5310
A/c pipe d 400 W-9	5000	427	377	390	6570
A/c pipe d 500 W-9	5000	528	466	637	7550

Based on these tables with prices, two conclusions can be drawn:

There are pressure pipes, and they are more durable than non-pressure ones. In turn, they cost more. To build a foundation from asbestos pipes, it will be enough to take non-pressure pipes of a popular diameter of 150-250mm. We must not forget that the main role of fixed formwork is not a constructive function, but the formation of reinforced concrete piles.
As you can see, the price of non-pressure a / c pipes is cheaper than PVC pipes for external sewage. But there is also a plus in the direction of PVC pipes, they have a higher range of lengths (1-6m), they are lighter, have a smoother outer surface, and the price of a pipe with a popular diameter of 200mm is almost the same as that of asbestos free-flow pipes.

Instructions for the construction of a columnar foundation from asbestos-cement pipes

Before proceeding with the marking of the site for the pillars, it is necessary to make calculations for the design of our foundation. It is necessary to determine the number of pillars and their location, determine the depth of drilling depending on the level of soil freezing.

4. We cut the a / c pipe to the length we need (above-ground part + underground part from the top of the soil to the top of the broadening). Then we attach the garbage bag to the bottom of our formwork with adhesive tape. The package will act as a barrier between the concrete and the soil during the formation of the widening. Basically, a barrier in the form of a package is needed if you have high groundwater and water begins to accumulate at the bottom of the well.

5. We form a reinforcing cage. The frame will consist of 4 bars of reinforcement with a diameter of 10-12mm. If you decide to also reinforce the widening at the bottom of the post, then the reinforcement is bent at the bottom in the form of the letter L. Then, when the reinforcing cage is inserted into the widening, you will need to unfold the reinforcement so that the bend looks at the edge of the widening. With this type of reinforcement, we make the frame weakly connected so that it is possible to rotate the reinforcement around its axis. (Below is a picture to make it clear.)

7. We insert the formwork from the a / c pipe into the well.

8. We form the broadening of the column. To do this, pour the first portion of concrete sufficient to fill the widening. Then we raise the post up so that the concrete fills the widening at the bottom of the well through the package. The last operation will be a slight indentation of the formwork down. Do not forget to vibrate or bayonet the concrete. You can bayonet with ordinary fittings.

All pillars should be at the same horizontal level. To do this, we beat off the level using a laser or hydraulic level. We stretch the twine according to the level. On it we will display all the pillars in one line. In order for the post not to sink into the widening, we will make a certain grip in the form of three bars fastened with a self-tapping screw on one side and tied with a rope on the other.
If it is difficult to set the formwork along the twine, then you can make it longer during the harvesting process and then cut all the piles into one level. The main thing is to make a mark on the formwork - to what level you will pour concrete.

9. We install the reinforcement cage in the formwork. The frame should be just below the edge of the formwork. Do not forget that in this example we have a columnar foundation for a timber strapping. If you have a pile-grillage foundation, then the reinforcing cage should be higher than the pillar.

10. To reinforce the heel of the column, unfold the reinforcement. The figure shows two reinforcing cages: without reinforcement of the column widening and with reinforcement.

11. Fill the column with concrete to the edge of the formwork. Do not forget to vibrate or bayonet the concrete to remove voids. Then, until the concrete has set, we fasten the anchor stud to connect the pole with the upper trim of the timber.
To calculate the composition of concrete, we suggest using our service:.

All. On this columnar foundation of asbestos pipes, we are ready. After pouring concrete, the end of the column must be covered with a film for the maturation of concrete. Do not forget also that all pillars must be made in the same level. www.site

From asbestos pipes with their own hands for private construction. However, this type of foundation is suitable only for the construction of light buildings: houses made of wood (timbered or chopped), or structures. The construction of heavy brick buildings on this type of foundation is not recommended.

Do-it-yourself pipe foundation. Economy and simplicity.

Many builders see the disadvantage of this foundation from asbestos-cement pipes is that during its construction it is not possible to arrange a basement or underground. In fact, this allows a significant part of the budget and not to bury hundreds of thousands of rubles, or even millions, that you will spend on concrete to store potatoes in winter. Nowadays, this type of construction is popular, especially in areas with a risk of flooding.

In addition, many are captivated not only by the economic benefits of this foundation, but also by the extreme simplicity of its construction, which is important if you are building a house with your own hands.

In terms of strength and durability, the foundation of asbestos-cement pipes is not inferior to other types of structures.

Basic calculations of the foundation of asbestos-cement pipes

The calculations will be based on:

the number of asbestos-cement pipes (1 for every 2.5-3 m.)
the required length of the actual pipes (depends on the depth of soil freezing and the planned elevation above the ground),
pipe diameter (according to the weight and dimensions of the building),
the required volume of concrete for pouring (for pouring ten-meter supports with a diameter of 10 cm, 0.1 cubic meters of concrete will be required, for supports with a diameter of 30 cm - 1 cubic meter of concrete mix),
the number of reinforcing bars (3-4 for each support).

Stages of building piles from pipes

The construction site is cleared along the width of the future building with an indent from the outer edges of 2-3 m. The upper fertile layer of the earth is replaced with a sand mixture.

2. On the prepared site, the future foundation is marked. To do this, pegs are stuck into the ground and a rope or fishing line is pulled, which is leveled with a level. The task of this markup is to control the erected supports, which should stand exactly and on the same level.

3. Next, the process of installing asbestos-cement pipes begins. On the marked area, wells are drilled, which should be slightly larger in diameter than the diameter of the pipes themselves. For work, you can use or ordinary construction.

4. Sand is poured at the bottom of the well, sometimes it is required to create a concrete pad wider than the diameter of the pipe. The sand at the bottom is compacted. If a concrete cushion was poured, it makes sense to wait for it to harden.

5. A waterproofing material is placed at the bottom of the well, which will be the concrete mixture from moisture loss.

Pouring concrete into an asbestos pipe through a sieve

When all these preparatory measures are completed, an asbestos-cement pipe is released into the hole. The support is fixed in a strictly vertical position and fixed with spacers.

How to fix an asbestos pipe for a foundation

A metal frame is placed inside the pipe and concrete is poured in portions, the mixture is processed with a vibrating drill to remove air pockets.

Pouring concrete through a sieve into an asbestos-cement pipe

Ready time for a pile foundation made of pipes

The foundation of asbestos-cement pipes is gaining strength up to 28-30 days, however, installation work can be started 14 days after the last support has been poured.

After installing all the supports and gaining strength with cement, the top layer of the foundation of asbestos-cement pipes is checked using a laser level and, if necessary, the excess parts are cut off.

During construction, building materials such as wood, metal or concrete mix can be used. The most durable will be made of concrete.

Conclusion on piles from pipes

This type of pipe foundation, which is made of asbestos cement, deserves special attention, because this is the cheapest type of foundation that you can make yourself. Do not forget that this type is suitable for light frame or, as well as small structures and baths.

So, we decided to build a frame or wooden house, or another light building (baths, terraces, etc.). Of the proposed types and varieties of the foundation, we will focus on a columnar foundation made using asbestos-cement pipes.

Advantage This type of foundation consists in the relative ease of manufacture, the availability of all materials used, the simplicity of operations, and, importantly, the low cost compared to other types. Also, this type of foundation is well suited for areas with high soil flooding, a large amount of melt water, places where it is very difficult or there is no access for special equipment at all or there is no possibility of its use.

First you need to determine the depth of the pillars on the site where the building itself will be built. Since the base of our pillar must necessarily rest on a solid support below the freezing point, the depth of the wells is also different for different latitudes. Here basic data by region:

Freezing depth up to 240 cm: Novosibirsk, Nizhnevartovsk, Vorkuta, Omsk, Surgut.
Freezing depth up to 210 cm: Tobolsk, Kurgan, Petropavlovsk.
Freezing depth up to 190 cm: Yekaterinburg, Orenburg, Ufa, Chelyabinsk.
Freezing depth up to 170 cm: Samara, Kazan, Izhevsk.
Freezing depth up to 150 cm: Moscow, Kostroma, Penza, Ryazan, Saratov.
Freezing depth up to 120 cm: Volgograd, Astrakhan, Smolensk.
Freezing depth up to 100 cm: Kaliningrad, Rostov, Belgorod.
Freezing depth up to 80 cm: Krasnodar, up to 60 cm: Nalchik, Stavropol.

The next step in calculating depth is type of soil where the building will stand:

Rocks and coarse stony soils, hard-consistent loams and clays, coarse and medium gravel sands - the depth of the wells depends on the depth of freezing in each case and the mass of the house.
Loams and clays of soft-plastic and fluid consistency, fine sands and dusty - the depth of the wells should always be no less than the estimated freezing depth.

After determining the depth our foundation pillars should be added to it another 15 cm below the freezing point. Also add another 40 cm to the height of the pillars above the surface. That is, if the estimated depth is 1.5 meters (150 cm), you should add: 150 + 15 + 40 \u003d 205 cm.

If you plan to build a building above one floor or the building itself is heavy (for example, a house made of logs), then you need to choose pipes 250 mm. and more.

Here is a small list of specific gravity of building materials:

Brick: clay 3500-3900 kg, silicate 3500-3700 kg per 1 thousand pieces.
Round forest of coniferous species: pine 670-760 kg, spruce 450-520 kg per 1 cubic meter.
Sawn timber: 600 kg softwood, 850 kg hardwood per 1 cubic meter.
Sleepers impregnated: 75 kg one piece.
Mineral wool: 75-150 kg per 1 cubic meter
Construction felt: 150-250 kg per 1 cubic meter
Construction sand: 1500-1650 kg per 1 cubic meter

Pipe selection. Asbestos-cement pipes are divided into two types:

Non-pressure, used to transport a medium without pressure. Cheaper ones are labeled "BNT".
Pressure, are used for transportation of the environment in the conditions of the increased pressure. More expensive ones are marked "BT".

Since our pipes do not carry any significant load, but are only a fixed formwork for the formation of reinforced concrete foundation columns, it makes no sense to buy pipes marked "BT", it will be enough for our purposes and simple non-pressure ones. The most common pipe length upon purchase is 5 meters, although for a diameter of 200 mm. you can find a performance of 3 meters 95 cm. One pipe with a diameter of 200 mm. and a length of 3950 mm. weighs 64 kg.

For a similar pipe 5000 mm long. weight will be 74 kg. Pipe with a diameter of 250 mm. already weighs 94 kg, 300 mm. - 121 kg, 400 mm. - 199 kg, 500 mm. - 359 kg. with a length of 5 meters. This will help you calculate the weight of each of your columns and determine the number of people needed to install the formwork into the ground.

average price on asbestos pipes for the foundation with a diameter of 200 mm. is 1200-1650 rubles per piece, for a pipe with a diameter of 250 mm. you will have to pay already 1700-1800 rubles, for a diameter of 300 mm. the cost is approaching 2500-2600 rubles. Large pipes with a diameter of 400 and 500 mm. cost approximately 4000 rubles for the first and 7600 rubles for the second.

Columnar foundation of asbestos-cement (asbestos or asbestos-cement) pipes, the first stage - markup. It is necessary to mark so that the pillars are necessarily at each corner of the building, at the intersection of the walls, as well as at the places of increased load. After that, the remaining pillars are marked in such a way that the distance between them is from one to two meters, it all depends on the thickness of the selected pipes and the mass of the future building.

Carry out the marking with the help of pegs and construction twine. Step back from the corner posts the selected distance and hammer in pegs around the entire perimeter of the future building. Then stretch the twine between the pegs located opposite each other. At the end of this work, you will get a grid of twine, where the intersection of the cords will be the center of the column. Mark them with pegs and remove the twine.

Well preparation. Clear the area of debris and level it. Remove the top layer of sod in the places of future posts. The thickness of the turf in the calculation of the depth of the column is not taken into account. Then you can start drilling. Measure the column by the outer diameter. We need wells as close as possible in their diameter to the outer diameter of the pipe. With a garden drill, a hand grab, or a specialized tool (for example, “boroya”), we drill wells in the soil to the calculated depth.

It is desirable to make an extension at the bottom of the well for more reliable support of the foundation. If this is not possible, do not worry, the method of how to get out of the situation will be described below. After all the wells are ready, it is necessary to make a support pillow for each column. Pour medium crushed stone 15-20 cm thick at the bottom of the well.

To find out the amount of crushed stone, simply mark the required depth on the pipe (for example, 20 cm), then pour the crushed stone to the mark.

Then pour the crushed stone into the bucket, level and mark the depth of filling the bucket (that is, a portion of the crushed stone). Now with a measuring bucket you can pour an even amount of crushed stone into each well. After all the wells are filled with the required amount of crushed stone, we proceed to cutting and installing pipes. If it is not possible to drill wells, we dig a pit for each pipe, fill in a pillow, set the pipe according to the level and ram the remaining void around the pipe with soil.

Pipe installation. If you are not sure that you can set all the pipes in a level way at once, then make a margin of 10 centimeters during cutting. After installing the pipes, cut off the excess along the level line. We install pipes in wells on a cushion of rubble. To fix the pipe strictly according to the level, you can use wooden wedges or a simple holder. Let's start with reinforcement.

Reinforcement of pillars. If our construction involves a flat flooring on poles or strapping using a bar, then the height of the reinforcement should be slightly lower than the column, if a pile-grillage foundation is meant, then the height of the reinforcement mesh should be higher than the foundation.

In some cases, installation of a stud into the foundation may be provided.

Do not forget that in order to securely fix the stud from below, it is necessary to fasten a steel heel cut from sheet metal with two nuts from above and below. In order not to clog the working part of the thread with concrete, wrap the length of the protruding part of the stud with masking tape. We make the reinforcing mesh in the form of a rectangular structure slightly smaller than the inner diameter of the pipe.

We carry out the lower part with hooks bent outward at 90 degrees. This will help us better reinforce the part of the foundation column expanded at the bottom. We lower the grid into each column. You can start pouring the foundation.

fill. We prepare a cement-concrete mortar using Portland cement grade 400, sifted river sand and medium-sized crushed stone. If we could not make an expansion at the bottom, then fill it by a quarter and raise the column a little, the solution will fill the vacated void and an expansion will be obtained at the base of the column. Let the concrete set for a few hours. We cut the pipes to the level. Then we continue filling.

If the expansion has already been performed in the well, then we pour concrete evenly and tamp it using a vibrating head.

In the absence of this useful tool, we pierce the concrete with a piece of reinforcement with bayonet movements to remove air. We pour and ram concrete into the gap between the pipe and the ground.

At the end of the filling, cover the end with a film for final maturation. We leave our foundation for two weeks, avoiding any work on the site. After the concrete has hardened, be sure to check the quality of the work performed, if you find voids between the pillars and the ground, carefully fill with concrete and tamp these places. Give it time to cool. Now you can start further construction.

So, sum up. According to numerous reviews of people who have already tested this method of construction, the following can be distinguished dignity:

Profitability. On average, a solid foundation is 30-35% of the cost of a house, in our case, the figure does not exceed 18%.
The possibility of self-construction - which also saves the budget.

Also, the positive qualities of such a foundation are especially distinguished in places prone to floods and flooding, as well as the possibility of building buildings on steep slopes.

Now oh significant shortcomings foundation on asbestos pipes:

The impossibility of building in moving soils due to low stability.
Not suitable for the construction of heavy structures and multi-storey buildings.

They require insulation of the ceiling under the house itself due to wind blowing and access "to the street".

Especially a lot reviews that during the construction of the foundation of asbestos-cement pipes, it is impossible to equip the basement and basement. And if possible, the rise in price is so great that it negates all the savings. And if the problem of the basement can still be solved by arranging the so-called "pickup", then the absence of a basement for many becomes a key negative factor in choosing this type of foundation.

For any building, the foundation is the fundamental structure, which largely affects the service life of the building, its stability and integrity. Therefore, its design and construction should be very responsibly and carefully prepared. Today, many developers, when building a private house, choose a base made of asbestos-cement pipes. Such columnar structures are best suited for the construction of frame buildings, wooden houses, light buildings, baths, terraces and other buildings.

The main advantages of foundations from asbestos-cement pipes

Column foundations are characterized by ease of installation, long service life, resistance to the negative effects of aggressive environments and affordable installation costs. In addition, the construction of asbestos-cement pipes can be equipped in places with difficult access and in remote areas that heavy equipment cannot reach to transport large-sized reinforced concrete slabs or a large amount of building materials.

It is based on a dispersed-reinforced composition. Asbestos is used as a reinforcing material, which, evenly distributed over the finished product, gives it increased strength and reliability, moisture resistance and durability.

Modern pipes have a long service life: 50 years or more. They are not subject to corrosion and have a low weight.

Preparatory work

Before you start building a foundation, you should study the design and technical documentation and calculate the exact amount of materials. For the arrangement of columnar structures, the following items will be needed:

Asbestos-cement pipes.
Hand grab or drill.
Cement, sand and gravel.
Fittings.
A container for mixing concrete mortar or a concrete mixer.

The diameter of the pipes is selected for each building individually, depending on the design load of the building and its structures, the characteristics of the soil on the site and the climatic characteristics of the region. For single-story and lightweight frame structures, products with a diameter of 200 mm can be used. For brick buildings, two-story houses and heavy buildings, it is recommended to purchase pipes with a diameter of at least 250 mm.

Before the start of work on the construction site, the sod is cut, the site is leveled, removing the top layer of soil. According to a pre-approved project, the location of the supports is indicated.

With the help of a drill or a hand grab, wells are equipped at a certain distance from each other.

The depth of the pillars is calculated in advance based on the data of geodetic surveys of the area. Experts advise deepening the supports 150 mm below the initial data on the depth of soil freezing on the site. As a rule, pipe poles are installed to a depth of 1500 mm.

Foundation construction technology: mortar preparation and pouring

Crushed stone is poured at the bottom of the wells, to a height of 150-200 mm. After that, pipes prepared in advance along the length are installed. After installation, the outer walls of the formwork are covered with soil.

In order for the foundation of asbestos-cement pipes to turn out to be of high quality and reliable, it is imperative to check the verticality of their installation.

Next, a solution of cement and concrete is prepared, cement grade 400, river, seeded sand and medium-sized gravel (crushed stone) are used. The prepared concrete composition fills each cavity first by one third. After that, the pipe is slightly raised so that the concrete spills over the base of the well and forms an expanded substrate at the bottom. This technique makes the foundation more stable, durable, durable and minimally susceptible to aggressive environmental influences.

After the substrate has set a little, the holes are completely filled with concrete, leaving approximately 150 mm or a little more to the top. Further, reinforcing rods are inserted into the cavity of each pipe. Having filled the columns with concrete to the end, they are waiting for the complete drying of the concrete composition.

The exact time for fixing the solution depends on the climatic conditions of work. As a rule, according to technology, it is recommended to wait at least 28 days. However, during the summer season this period can be reduced to 21 days.

Thus, using these simple tips and rules, you can independently prepare a high-quality and reliable columnar foundation for any residential building or outbuilding.