The construction of the road foundation from sand and gravel mixture and OGS. Sand and gravel mixture: features and scope Under a monolithic slab

The ISO Altair company offers to buy a sand and gravel mixture that meets the requirements of GOST 23735-2014. We deliver with our own fleet, 7 days a week, without holidays and weekends. We supply up to 2000 cubic meters of sand and gravel mixture per day.

Under the order we will make the necessary ratio of sand and gravel.
The price of PGS according to your parameters is discussed individually. Call!

Price for sand and gravel mix

The table below shows base prices company "ISO Altair" for sand and gravel.

ISO "Altair" is equipped with a car park. Therefore, the truck with the load is sent from the warehouse immediately after the payment of the order. The transport department and the order department work around the clock. The client receives the sand and gravel mixture at the specified address within a few hours after placing the order. Each batch of PGS is certified.

This material is a mixture of gravel and sand. The fractionation of the sand-gravel mixture is heterogeneous: the diameter of the grains of sand and pebbles is not the same here.
Sand and gravel mixture is an environmentally friendly natural material. Mined open way in quarries using excavators. This mortar coarse, its use is limited. ISO "Altair" among the non-metallic building materials sells in Moscow and the region and sand-gravel mixture.

Characteristics of PGS

The ratio of sand and gravel in the sand-gravel mixture is not the same.

• Natural ASG is a coarse material with impurities. No additional processing of the mass after its extraction is done. Such a mixture is subdivided, depending on the place of extraction, into mountain-ravine, lake-river or sea. Natural ASG is used in land reclamation and in road construction for filling the drainage layer. The company delivers the natural mixture to customers in the form in which the raw material was mined in the quarry. The size of the pebbles in this mixture exceeds 5 mm in diameter, and their number in total mass is no more than 10%.
• Enriched sand-gravel mixture is artificial material, consisting of sand and granite chips of a given size. The quality of the material depends on this. The grades of the mixture differ in the ratio of sand and gravel and the size of the pebbles. The demanded brand of PGS is the one in which the content of granite chips is 70%, and sand - 30%.

Enriched PGM is divided into 5 types:

• group 1 - from 15 to 25% gravel;
• group 2 - from 25 to 35% gravel;
• group 3 - from 35 to 50% gravel;
• group 4 - from 50 to 65% gravel;
• Group 5 - from 65 to 75% gravel.

Application of PGS

Sand and gravel mixture is used when laying communication lines, during foundation works, when backfilling pits, as well as in construction and in laying roads. It is purchased for bedding highways, laying drainage collectors and even sometimes for cooking mortars. True, the latter are made only using enriched PGS.
The Moscow region is very rich in deposits of this natural material. Its extraction here is well established, and therefore the cost of natural ASG is low. It is difficult to find prices for ASG in the region cheaper than in Altair.

5 reasons to buy PGS at ISO Altair

1. ASG is delivered to the customer on the day of payment, since a sufficient number of dump trucks and handling equipment are provided for this. In addition, a stock of this material is available at the transshipment bases.
2. The company sells only certified PGS.
3. On a permanent basis there is a system of discounts for regular and wholesale customers.
4. The departments of the company work around the clock and seven days a week.
5. ISO "Altair" offers the cheapest price in the region for PGS and accepts payment in a convenient way for the buyer.

The foundation is not only the basis of any building, but also the guarantor of the durability and strength of the building. Exactly right choice and compliance with a strict sequence of work, as well as the competent selection of materials used in the construction of the foundation, guarantee its reliability and compliance with the required quality standards. The main purpose of this part of the house is to provide the future building with a stable and strong platform. A properly prepared and laid sand and gravel cushion under the foundation is able to provide it with a lesser degree of settlement. Thus, a reliable pillow helps to significantly improve its quality.

In the event that the construction of the foundation is carried out without observing the necessary building codes and contrary to existing and time-tested rules, the building was built in a very short time may become completely uninhabitable. Cracks appear on the surface of the walls, window frames warped, the doors no longer close tightly. All this leads to the appearance of mold, dampness, drafts.

The renovation and decoration of the premises is losing its attractiveness. The owners of such unsuccessful buildings have to invest additional funds, time and money in unforeseen repairs.

Compliance with all requirements for the construction of the foundation will help to avoid disappointment. And its correctness depends on how exactly the sand and gravel cushion under the foundation was made. It is rightfully considered the key to a strong and solid foundation. The pillow ensures the complete absence of contact between building materials and building objects with the foundation itself, which, in turn, eliminates the appearance of various deformations. Due to the presence of a well-chosen and prepared pillow, the building (at its very bottom) rises high in relation to ground water.

A mixture of sand and gravel is one of the most popular and commonly used building materials. Both of these components, mixed in strict accordance with the recommended proportions, are very often used for construction. residential buildings, shops and other buildings. This seemingly simple composition belongs to one of the most the best options basics. It guarantees the strength of the mixture of mortar from concrete or cement.

Why do you need a pillow under the foundation?

Those who are thinking about making the foundation for the construction themselves should pay attention to well-formed building regulations regarding this issue. First of all, it is important to comply with all the requirements for such a stage of work as the installation of a sand and gravel cushion. In addition to a pillow made from a combination of sand and gravel, pillows for a foundation made of concrete and gravel are common. As a rule, a concrete cushion is required only when performing under FBS blocks reinforced belt or with additional expansion of the walls of the foundation.

The sand and gravel pillow is made on construction sites with weakly bearing soil. It is important to remember that in no case should sand dust or fine-grained sand be used to form it. The ready-to-use mixture must consist of gravel and sand, which have an average particle size. After the pillow from this composition is laid, it will give a minimum shrinkage, for which it is necessary to make careful tamping. Such a base for the foundation will perfectly withstand the load of not only a medium-sized house built from frame building materials, timber or logs, but also a building of a large area, for example, with an attic or a second or third floor.

When building a sand and gravel support, you can use the following work option:

1. dig a trench of the required width and depth up to the level of dense layers of soil;
2. into the ditch, which thus turns out, must be filled river sand coarse-grained brand;
3. sand should be covered in layers and in small portions. Each layer should be 15 cm thick;
4. after laying each new layer, it must be spilled with water;
5. all layers are compacted using special tamping equipment;
6. the finished support should have a width of 10 mm greater than the planned width of the future building.

The need for a sand and gravel cushion in the construction of not only low-rise, but also larger ones is determined by its relatively affordable cost, a high degree of durability and the ability to carry out work on their own, without the help of professional builders. However, it should be noted that such trifles as cleaning the trench after an excavator, backfilling sand and gravel with buckets or a wheelbarrow, manually watering all layers with water will require serious physical effort from workers. An attempt to involve family members or friends in the process may well be justified.

Do-it-yourself sand and gravel pillow

Every experienced master builder knows what a sand and gravel cushion is for. Such a foundation under the foundation is able to ensure the subsequently built building full functioning without defects and damage. It must be remembered that the layers of the sand-gravel mixture are laid in layers, but in different thickness each such layer. The fact is that this question is fundamental for each individual type of soil. In no case should a layer of sand and gravel be less than 5 cm thick. Many builders do not welcome a pillow thickness of more than 25 cm.

It is desirable to equip the pillow under the entire area of ​​​​the building. It is this method of laying that provides the most uniform draft of the structure. The width of such a pillow should be wider than the width of the foundation base by at least 30 cm. Thus, the structure is supported over its entire surface area. When laying a sand and gravel cushion, it should be compacted so intensively that it acquires a density equal to 1.6 g / cm3 of the density of the soil layers.

Doing such work yourself, monitor the quality of the building materials used. So, for example, the presence of even a small amount of clay impurities in sand can lead to serious unpleasant consequences. If water gets into such a pillow, it will begin to swell. Therefore, control the composition and condition of the materials used, and also, be sure to follow the recommendations and step by step instructions at all stages of work.

Many novice builders think about when and how to make a sand and gravel pillow with their own hands. The solution to this problem is quite accessible to master everyone. And since laying the foundation is the first step in the construction of any building, its implementation requires a serious and responsible approach. The depth of the foundation is primarily determined by the level of water flow in the soil. With a large depth of laying the foundation, it is not complete without a sand and gravel cushion.

Having decided what a sand and gravel cushion is, you can proceed with its installation, which basically boils down to the following:

• it resembles a kind of “pie” with layers of sand and gravel (you can use crushed stone);
• the first layer in a dug trench (pit) is a rubble, which will provide additional strength;
• the second layer is coarse river sand, which, after being distributed over the entire surface, must be leveled, watered and compacted;
• the third layer, at least 20 cm thick, is gravel. After laying, it is rammed with a vibrating plate;
• ready-made layers are covered with a layer of sand equal to 20 cm. After it is watered, it precipitates on gravel.

This technology must be followed layer by layer until the wet sand has nowhere to settle. After completing the work on the manufacture of the pillow, you can begin to build the foundation.

The subtleties of building a shallow foundation

The shallow foundation is a monolithic tape, mainly made of reinforced concrete. The height of such a tape is from 40 to 60 cm, and its width is 35 - 50 cm. These indicators depend on the thickness of the walls and the materials from which they are built. Laying such a foundation under the building is carried out under all external and internal load-bearing walls.

Highly important point the construction of such a foundation can be called the installation of the correct pillow, in which only components that are not subject to heaving should be used. Ideal Components for it will be sand and gravel. In this case, the ratio of these components can be approximately as follows:

• river sand of large fractions - 60%;
• gravel - 40%.

Such a mixture replaces the soil and is laid on the bottom of the prepared trench. Most often, the depth of the trench is about 50 cm. All laid materials are subjected to ramming. This bedding significantly reduces the impact on the foundation of heaving forces during frosts. The sand and gravel mixture neutralizes and springs the impact coming to the base of the structure from below.

To the benefits shallow foundation its low cost and lack of high labor intensity. However, with this choice, the size of the future building is limited, for example, the walls should not exceed 7 m. As for the device basements, then with this type of foundation they are not provided.

Laying the foundation of the house is the first and most important stage of construction, but this is preceded by the preparation of the foundation under the entire building spot on the site.

The type of foundation, its design and characteristics depend on the bearing capacity of the soil at the construction site, as well as the strength of the house that will be built subsequently.

Even at the design stage, it is necessary to determine the properties of the soils and determine which sand or crushed stone bedding under the foundation will be relevant as a preparation.

It is somewhat incorrect to raise the question of choosing a backfill for a foundation of sand or gravel. The key to a strong and sustainable home is a solid and reliable foundation, which must meet a number of requirements:

• High strength and density of the soil, capable of withstanding the distributed load of further development;
• Ground water should not linger under the base, therefore the high drainage capacity of the soil is important;
• When wet or dry, the base should not lose its basic characteristics.
• It should not contain organically active components;
• The presence of combustible or plant residues capable of decay is not allowed.
• Cold heaving of the soil is not allowed;
• Uneven shrinkage or deformation is not allowed.

In progress construction works the base should not be deformed even under the load of the involved construction equipment or the activity of the builders.

The strength of the surface layer should be sufficient to accommodate all necessary elements such as reinforcing frame, formwork, etc.

bedding device

Since it will not be possible to select the type of soil on the site in advance, you should work with what is in fact. If the soil does not meet the specified requirements, a bedding under the foundation is used from:

• sand;
• gravel;
• sand and gravel mixture (SGM);
• gruss (crushed rock fragmentation type);
• crushed stone;
• lean concrete.

Since the properties of each of the listed materials are different, as well as the methods of their use, the choice of bedding should be carried out based on the final requirements for the base for the foundation.

The main conclusion: backfilling under the foundation of sand or gravel is needed to adjust the properties of the soil on which the house will be built. It is part of the foundation preparation activities and is not an unconditional component.

Anyway according to the type of soil, it is first determined optimal type foundation(tape, pile, monolithic slab, etc.) and after that, if necessary, the type of bedding that is required is selected.

Quality preparation for strip foundation or monolithic slab is to fill the bottom of the pit with lean concrete to level the level and prepare a solid foundation. Sand or gravel is for the most part a cheap alternative to reduce total costs for construction.

Sand

simple and enough effective option bedding under the foundation. well packed mechanically the sand cushion is able to take the same strength and density as the main soil, and at the same time it is easily molded to match all the unevenness of the bottom of the pit.

Benefits of backfill sand:

• With high-quality ramming, it is possible to achieve a base strength equal to the initial value for the soil;
• Well fills all the irregularities of the pit and transfers the load evenly;
• Sand retains drainage properties;
• Easily molded and leveled;
• Does not require the involvement of heavy construction equipment.

Disadvantages:

• Weak mechanical strength transverse point load.
• Sand is washed away by groundwater over time.

Sand for backfilling is ideal in the case of using precast concrete blocks and slabs, allowing the load to be transferred evenly throughout the base.

Sand for backfilling is selected large and medium fractions without clay inclusions. Even with full tamping, the drainage properties of the base are preserved, and cold heaving has almost no effect on the strength of the base.

The thickness of the bedding can be from 10 to 60-70 cm depending on soil properties. The depth of soil freezing in many regions of the country exceeds 30 cm, and cold heaving can occur even under a well-insulated foundation during prolonged winter cold snaps.

The optimal height for adding sand is considered to be 45-60 cm. It is difficult to compact such a layer of sand at a time, therefore the material is gradually covered with layers of 5 cm thick and gradual tamping and mandatory moistening.

It is quite difficult to determine the required amount of water to moisten the sand. Common mistake is excessive wetting of the sand, from which the entire mass acquires plasticity and diverges more on the sides of the rammer than it compacts.

The volume of liquid should be determined individually so that the sand is easily crushed in the hands, keeping the shape of the cake. On the other hand, with mechanical compaction, water should not protrude over the sand.

The degree of compaction of sand is quite simply determined. If no traces remain on the prepared sand cushion when walking on it, then the base is ready for further work.

Gravel

For backfilling, gravel of medium and coarse fractions is used in those situations when under the base of the foundation it is necessary to ensure the maximum throughput of the drainage layer in combination with the distributed drainage system, focused on the removal of groundwater from the base of the foundation.

Gravel is often used as a cheap substitute for lean concrete in preparing and strengthening soil for foundations. To do this, it is tamped and mixed with the soil mechanically or manually.

However, this is not The best decision, since without a binder, which can be cement, such a base is subject to erosion by groundwater, followed by loss of bearing strength.

More often, ASG is in demand - a sand and gravel mixture for the formation of a flat area under the foundation. In combination with sand, the mixture is easier to give a density and strength comparable to that of the parent soil on construction site while retaining the drainage capacity of the bedding.

Benefits of gravel bedding:

• The low water capacity of the substrate, the liquid is poorly retained in it, and the surface area of ​​the gravel for wetting is much lower than that of sand;
• Backfill strength and high load capacity and resistance to scouring or lateral loads.

Disadvantages:

• Under heavy loads, even distributed, gravel bed can "drown", reducing its own strength and strength of the parent soil;
• It is difficult to level the surface of the backfill;
• When concrete is poured, part of the laitance sinks aimlessly through the bedding, weakening the main body of the foundation.

If gravel is used for backfilling under a strip foundation or a monolithic slab, then, of course, it should be pre-insulated to prevent weakening of the concrete. However, this often brings more costs than when using initially lean concrete.

What is better sand or gravel

The requirements for preparing the base of the foundation pit require strict guidelines in the construction project based on an analysis of the bearing capacity and properties of the parent soil.

The best preparation for a strip foundation or a monolithic slab is lean concrete and only in some cases is it allowed to replace concrete with sand, gravel or ASG to reduce overall costs. At the same time, sand has a large set of advantages and is more practical.

Gravel is suitable only in cases where high throughput if necessary, the arrangement of a drainage layer with low water capacity. At the same time, it is difficult to isolate the bedding from the volume in which the foundation will be poured.

Gravel padding goes well with pile foundations, where it is enough to remove excess moisture from under the base of the house, and at the same time, there will not be a significant load on the bedding itself.

Under the strip foundation

Sand filling is needed, by definition, only if ready-made reinforced concrete slabs and blocks to distribute the load evenly over the plane of the base.

With the help of sand, it is easier to level the bottom of the pit, and tamping gives the sand the necessary density and bearing capacity.

However, this is only relevant if it is possible to place a massive vibrating plate in the trench for mechanical sand compaction. In most cases, it is safer to use lean concrete footing to level the base and prepare.

Sand is also relevant in case of significant height differences along the bottom of the prepared trench. To reduce costs and reduce the volume of mortar for footing, sand or crushed stone is used with layer-by-layer tamping and moistening.

Under a monolithic slab

It is important to strictly bring out the plane of the base of the pit and prepare the soil for the installation of the reinforcing frame and pouring. Either lean concrete or compacted sand is used in layers.

construction stages monolithic foundation

Sand is mainly used in cases where it is necessary to significantly raise the bottom of the foundation pit after sampling the entire fertile soil layer to the base of the parent soil.

When forming the bedding, it is important to pre-distribute the trays for water drainage, the supply lines of communications that will pass through the foundation slab, and also to mark the required planes of the future base.

According to the requirements, a base is formed under a monolithic slab not strictly in one plane, but with a slight elevation in the center of the building and with a slope of 2-3% in all directions, for effective removal of moisture from the substrate of the future foundation.

Particular attention is paid to the quality of sand compaction. So the density of the bedding under the foundation should be from 1.65 t/m3 and preferably not less than the density of the parent soil with an error within 0.05 t/m3.

The height of the bedding is determined as the difference between the level of the bare soil base after the removal of the fertile layer and the design level of the foundation base.

Under the pile foundation

The backfill primarily performs the function of drainage for the removal of groundwater, and also acts as a substitute for the fertile soil layer in order to remove the volume of material containing organic or combustible inclusions from under the foundation.

pile foundation bedding device

For these purposes, it is best to use large and medium gravel, crushed stone. Expanded clay bedding is often used, which additionally increase thermal insulation properties grounds.

PGS is a high-quality, purified mixture of sand and gravel. Thus, the sand-gravel mixture refers to non-metallic materials used in the construction of residential and industrial use, creating high quality pavement, in railway construction, when laying drainage layers, for leveling areas in landscape design, for making iron concrete products used for construction panel buildings. Also adding ASG necessary to create a cushion for the construction of the foundation, equipment sites for the operation of special equipment and in the construction of roads, for backfilling trenches and pits.

Can be natural and enriched. It is mined in quarries or from the bottom of reservoirs. Natural ASG contains at least fifteen percent of gravel, and in an enriched mixture, the content of gravel can significantly exceed this figure. The enriched ASG differs in the content of gravel into five groups: 15-25%, 25-35%, 35-50%, 50-65%, 65-75%. The more gravel the mixture contains, the harder it is, respectively. Gravel is introduced into the mixture artificially in production. The price of enriched ASG depends on the amount of gravel in it and its size. Both types of PGS are characterized by durability and resistance to physical influences, which contributes to their widespread use. If you need such high quality materials, then construction company offers to buy and deliver all the necessary building non-metallic materials: sand, crushed stone, gravel, bedding, PGS other.

The backfill, as a rule, is made of non-porous soil, and instead of the ASG, building soil is also used as a backfill no smaller than medium-grained. The amount of backfill is determined by a special temperature calculation, and it has to provide for ventilation and thermal insulation so that it is not too large. PGS filling is used for arranging a monolithic foundation one- or two-story house. The installation of such a foundation begins with the development of a pit, tamping and creating a pillow, using ASG bedding, sand and gravel. Laid on top of it waterproofing material and pour a small layer of concrete, then the reinforcement is laid, and the foundation pit is poured special solution concrete. The result is a solid monolithic slab used for the basement floor.

The technology of erecting various structures on initial stage construction also almost always implies the arrangement of a site for work (this requires backfilling). Backfilling of sites and roads is a crucial stage of any construction. Thus, depending on the type of structure, climatic and geographical conditions, the filtration properties of the material largely depends on the quality and operational life of the buildings, therefore, for arranging the cushion of the canvas, the base device is used adding ASG, crushed stone, sand - High Quality. The technology consists of several stages:

• First, with the help of a bulldozer or excavator, they remove upper layer soil up to hard rock, this is necessary to insulate the base of the future structure.
• Then soil rollers strengthen the soil and form a platform for subsequent work.
• The pillow itself and compaction are carried out using the addition of ASG, crushed stone, sand.
• Additional bedding of hard rocks of crushed stone and its compaction are possible.