What are the proportions for the foundation? Proportions of concrete mixture components for the foundation. Main brands of concrete mixtures

Concrete- an important component of any construction. The operational characteristics of the structure being built largely depend on the foundation. Therefore, it is very important to properly prepare the solution for pouring it. Concrete mortar for large-scale construction projects is prepared in a factory.

Private developers, when building a house with their own hands, usually prepare it themselves in order to at least slightly reduce construction costs. Having chosen to prepare it yourself, it is important to observe the proportions for the concrete for the foundation. After all, the strength of the foundation of the house often depends on this.

Choice

The foundation is the load-bearing part of any building. To make it resistant to various loads, you need to choose the right concrete composition for it. In this case, its resistance to compressive loads will be sufficient, which means it can withstand the pressure of the entire house. Various are produced, therefore there are several composition options. Which one to choose for pouring the foundation? This question must be answered taking into account two factors:

1. Features of the structure (number of floors, weight, size of the basement).
2. Features of the soil on the site.

The choice of composition taking into account the first factor is made as follows:

1. M 150 is used for pouring foundations for frame and panel buildings.
2. For light houses made of logs and timber, M 200 is selected.
3. M 300 for block and brick buildings.

The dependence on the characteristics of the site is as follows. The more complex the soil on the site, the higher the grade of concrete you need to choose. So, for rocky soil it is enough to prepare a solution of M 150. For loamy soil, the composition M 200 is suitable.

Components

Any concrete, regardless of its brand, consists of the following components:

1. Cement.
2. Sand.
3. Crushed stones or gravel.
4. Water.

All these components must have required characteristics, taking into account which they need to be selected. Cement is the main ingredient in a concrete mixture because it is a binder. It is produced by cement factories. Cement is divided by grade and by the number of various additives it contains. The most popular Portland cement, it contains many special additives to improve the properties of the material. When pouring the foundation of a house, experts recommend that private developers use cement M 400 or PC 400.

You need to keep in mind, like many building mixtures, the shelf life of cement is limited. After a year of storage in packaging, it significantly loses its activity, which determines the properties and brand of the material.

Sand is one of the fillers for concrete mixtures. To obtain a high-quality solution, you need to take its choice seriously. It is worth noting that at the moment the choice of sand on the construction market is huge. If you wish, you can even purchase sand from the seabed, but not every sand material is suitable for concrete.

Thus, experts do not recommend using sand with clay admixtures for this purpose. Because of this, concrete is less durable and frost-resistant. But with river sand you can prepare a solution that is ideal in condition. It is often of very high quality and consists of homogeneous fractions.

and gravel just like sand in the solution acts as fillers. Thanks to them, the solution “shrinks” less, which makes concrete structure more durable and durable. When choosing crushed stone, you should pay attention to its shape. Because the convenience of pouring concrete mortar depends on it.

Flat and angular crushed stone is usually not used for mixing concrete. Because it requires more consumption of other components, which affects the strength of the structure. The best option for pouring the foundation is the use of crushed gravel. It consists of particles ranging in size from 3 to 70 mm. In addition, it is affordable for private developers.

Water. This component can have any characteristics, the main thing is that the water is clean without any impurities. Having all the above components and knowing the proportions of concrete for the foundation, you can prepare a solution of any required brand.

Video

Video on how to make concrete, as well as proportions in buckets.

Component proportions

The correct ratio in concrete mortar components is the key to obtaining high-quality material. The optimal composition of concrete for the foundation for the construction of a private house is considered to be one part cement powder to four parts crushed stone (1/4). And in the proportion of cement and sand, the ratio is 1/3, that is, for 1 part of cement (M 400) there are 3 parts of sand. In general, the weight of cement in the cement mortar should be 1/4 of the total mass.

But concrete still needs water to harden. An important characteristic of concrete is the proportion of water and cement (the so-called water-cement ratio). The strength of concrete depends on this ratio: the lower its value, the stronger the material. For a concrete mixture used for concreting foundations, the maximum water-cement value is 0.75.

For private developers, for a small amount of work, it is easier to mix the mortar on the construction site. One batch of foundation mortar is made in a concrete mixer in approximately the following proportion:

1. 300 kg of cement powder.
2. 600 kg of sand.
3. 1300 kg of crushed stone.

But the developer does not have the ability to weigh bulk materials when he is at the construction site. A completely reasonable question arises: how to make a foundation mortar correctly. To do this, you need to know the proportions of concrete for the foundation in buckets. Since all components have approximately the same bulk density, you can measure them and then the composition of the concrete for the foundation, the proportions in buckets will be something like this:

• Cement 25 buckets.
• Sand 43 buckets.
• Crushed stone 90 buckets.

When determining the amount of water, they are guided by the measure of cement: for one bucket of cement powder you need to add an incomplete bucket of water. This volume may vary depending on the situation. For example, if it is reinforced, then the concrete is mixed with more plasticity so that it penetrates inside the frame more easily.

It is more practical to make it rigid, this will speed up the hardening. In both cases, you need to add enough water so that there are no puddles in the finished solution. To obtain one cube of concrete of different grades, the optimal ratio of components in volumetric terms is presented in the table.

In these volumetric indicators, the bucket can be replaced by any volume measure, provided that the proportion is maintained.

When deciding how to prepare concrete for the foundation, you need to keep in mind that in addition to the proportions, you need to know in what sequence to lay the components. First, water is poured into the concrete mixer, slightly less than normal. Then half a portion of crushed stone is poured. And only then, cement with sand and again all components are thoroughly mixed.

At the very end, the remaining crushed stone is poured. After this, you need to give the concrete mixer a little time so that it thoroughly mixes all the components. And finally, having assessed the thickness of the solution, depending on the situation, add the rest of the water or leave it as is and mix everything thoroughly again.

Conclusion

After the foundation casting has reached the calculated hardness, to get rid of doubts about the correctness You can check the proportions and grade of concrete. To do this, place the chisel on the surface of the casting and hit it with a hammer. On ordinary concrete M 200 there should be a dent no more than 5 mm deep.

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Every building, regardless of its purpose, needs a strong support; the reliability of the building and its durability depend on its quality. The foundation may have different shapes and consist of various materials. However, in any case, the main component of the foundation is concrete.

Proportions of concrete for the foundation

Foundation concrete is a combination of binder, filler, water and various additives.

The binder is almost always cement, which, depending on the load to withstand, can be of several grades: M200, M300, M400, M500 and M600.

Sand and crushed stone are used as filler. It is best to use river sand, and it should not contain clay impurities. The size of sand grains for high-quality concrete should not exceed 5 mm. It is better to take from crushed granite, as it is characterized by high strength. The fraction size should not exceed 2 cm.

Additives are necessary to give concrete the required characteristics. The mixture of dry ingredients is diluted with water to the desired consistency. Each component of concrete has its own function, so it is very important to choose the correct proportions of the components.

The water for preparing concrete must be clean, so it is recommended to take it from water supplies. If this is not possible, then it is allowed to use water from natural reservoirs, but with preliminary purification.

You can mix the concrete solution in a concrete mixer or manually using a certain amount of components. However, weighing materials is not always possible, so buckets are used for convenient measurement.

• Cement - 1 part.
• Sand - 3 parts.
• Crushed stone – 5 parts.

In other words, for high-quality concrete, for 1 bucket of cement, take 3 buckets of sand and 5 buckets of crushed stone. As for water, the calculated amount of this component is determined depending on the amount of cement; most often they take 0.5 parts of water to 1 part of cement. However, there are many factors that influence the amount of water to varying degrees. For example, using wet sand significantly reduces the water consumption to prepare a solution of the desired consistency. In addition, it is necessary to visually control the consistency of the concrete. The main thing is that it is thick and flexible, can hold its shape and not spread.

Proportions of components for preparing 1 cubic meter. concrete

Foundation concrete has several grades, which are determined by the type of future structure, its weight and purpose. To prepare each brand of concrete, a specific brand of cement can be used. In general, these two factors determine the number of ingredients needed to prepare one cubic meter concrete.

In most cases, concrete grade M 200 is used for the construction of foundations; it has sufficient strength and can withstand freezing and thawing many times. To make such a solution, M500 grade cement, medium-fraction crushed stone and water from the water supply are used.

To prepare one cubic meter of M200 concrete, you need to take the following number of components:

• Cement – ​​300-350 kg.
• Crushed stone – 1100-1200 kg.
• Sand – 600-700 kg.
• Water – 150-180 l.

To translate specified values in volume in buckets for more convenient measurement, it is enough to know the approximate mass of each component in one bucket. For example, a 10 liter bucket holds 15.6 kg of cement, 19.5 kg of sand and 17 kg of fine crushed stone. Therefore, to mix a concrete mass with a volume of 1 m 3 you will need approximately 20 buckets of cement, 30 buckets of sand, about 70 buckets of crushed stone and 15-20 buckets of water. As you can see, calculating the proportions of concrete for the foundation in buckets is not so difficult.

Features of concrete mortar

The strength of the foundation largely depends on the correctly selected components, each of which is designed to perform its assigned task.

For example, the main components of concrete are cement and water; their mixture forms cement stone. However, despite the monolithic structure, this stone is easily deformed, shrinking 2 mm per 1 meter. The result of this process is the formation of microcracks, invisible during visual inspection, but significantly reducing the quality of the cement. In the future, to analyze the quality and condition of the foundation.

Reduce the degree of deformation cement stone Fillers help. Most often, sand, crushed stone, gravel or expanded clay are used for this. The filler forms a special structure that absorbs the stress of concrete during the shrinkage process. Consequently, adding a filler to cement makes it possible to increase the strength of concrete several times.

Manual preparation of concrete mixture

To prepare a high-quality concrete solution for the foundation, it is best to use a concrete mixer. However, this possibility is not always available. Sometimes purchasing or renting a concrete mixer is unavailable due to limited budget for construction. There are situations when it is not possible to connect to the power supply. It is possible that using a concrete mixer is not rational due to the small amount of work. Problems of this kind can be solved by manually mixing the concrete mixture.

To work you will need the following:

• Two buckets: one bucket for cement, the other for other components and water.
• Two shovels, one of which is also used only for cement, the other works with sand and crushed stone.
• Wide container with high sides for easy mixing of ingredients.

The process of manual mixing of concrete mixture is as follows:

1. Sand and crushed stone are poured into the container, mixed well and grooves are made on the surface.
2. Cement is poured into the resulting recesses and the entire mixture is mixed until homogeneous.
3. The mixture of dry ingredients is collected into a cone, at the top of which a hole is made.
4. Pour a small amount of water into the recess of the cone and begin to mix. In this case, the kneading is carried out directly at the top of the cone so that the dry mixture is poured into the hole with water.
5. When the poured water is absorbed, a cone is formed again with a depression in the upper part and more water is added. The steps are repeated until the required consistency of the concrete mass is obtained. It is very important not to pour all the water at once, as too much water can reduce the quality of the prepared solution.

Preparing concrete for the foundation is a very important stage, on which the strength and durability of the foundation and the entire structure depends. Therefore, it is very important to correctly select the components for mixing the concrete mass and calculate their proportions as accurately as possible.

When starting any construction, we want the constructed building to be strong and reliable, and for this it is necessary, first of all, to make a high-quality and durable foundation. It is pointless to build high and strong walls if, when laying the foundation, you do not provide the required quality and proportions of the concrete solution. And given the considerable weight of the building and the load, for the foundation they become a “golden key”, which opens up the opportunity to build up the walls of the building, regardless of weather factors, alterations and modifications, if the structure is installed on a powerful and durable foundation.

Types of foundations

Depending on the weight of the building being erected and the type of soil on which construction is being carried out, the type of foundation is selected:

• Tape - performed along the perimeter of the building under the main load-bearing walls designs;
• Slab - poured with a solid slab covering the entire area of ​​the building, the most expensive option in terms of materials and labor intensity;
• Columnar - used mainly for small structures, outbuildings, gazebos and other options that do not have much weight;
• Ribbon-column– is a combination of elements both columnar and strip foundation, By material costs will cost less than tape.

Important! When pouring and hardening, the concrete mixture often behaves in the most unpredictable way, so The best way To obtain a high quality foundation structure is to fill the formwork in one go.

In this case, the shrinkage of the material will be more or less uniform, even if the proportions of ingredients spent on concrete for the foundation with your own hands were not maintained exactly.

Composition of concrete for foundation mixing proportions

It is not always worthwhile to strive to obtain a foundation of the highest strength and rigidity. In some cases, this approach is a waste of money, and sometimes such a decision directly contradicts the requirements for the foundation system of a particular building.

To make it easier to navigate the different proportions of preparing concrete mixtures, an index or grade is assigned to a specific concrete composition to characterize the strength and rigidity. M150 concrete is used for concreting minor objects, for example, you can make supports for a fence or the foundation of a light frame building. Brand M200-250 is widely used for the foundation of most private houses, one-story buildings with low load on the ground. M300 - suitable for two-story brick houses, M-400 is used in industrial construction.

Requirements for concrete for foundation

To prepare concrete of any grade, the same ingredients are used:

1. Cement is the main active element of a concrete mixture; it acts as a binder and holds together all other components into a single whole;
2. Sand is a filler that fills voids and acts as a cheaper cement substitute;
3. Gravel or crushed stone– it is better to use fractions with sizes from 1 to 5 cm, preferably a material with a rough surface, it helps to increase the strength of concrete;
4. Water – pure drinking water is used, not containing any impurities or additives.

Important! Please note that cement, like food, has its own expiration date. After just a year of storage in packaged form, the strength of cement in finished concrete decreases by 20-25%. Moreover, the decrease in characteristics occurs unevenly, in different packages in different ways, even within the same batch.

Usually in construction work Cement grades M400 and M500 are used.

The sand for preparing concrete must be clean; you can use river or quarry sand; you must check that it does not contain clay impurities, as this will negatively affect the strength of the foundation.

To check the purity of the sand you are going to use, pour some sand into a clear bottle, add water and shake. Then evaluate the clarity of the water in the bottle. If the water is clear or slightly cloudy, this sand can be used to prepare a concrete solution for pouring foundation structures. If the water in the bottle is cloudy or colored, the sand will have to be rinsed or replaced.

In addition, the sand used to build the foundation must be sifted before mixing the concrete mixture. No plant debris, twigs, leftover leaves, or pieces of soil should get into the concrete foundation solution. All these plant inclusions negatively affect the quality of the poured foundation.

Crushed stone or gravel used in concrete for the foundation must also be clean, without soil or organic matter. Before mixing the mixture, you can rinse the gravel with clean water to ensure its cleanliness.

For mixing concrete mortar, use only clean water. To avoid problems with the strength of the foundation system later, water from ponds and lakes, especially sea water, should not be added to concrete. The water should not contain salt impurities or any organic residues.

What proportions to use

If you need to prepare concrete yourself, use the proportions given in the table. A construction site is not a store, and no one will weigh the ingredients, and the proportions must be maintained as accurately as possible. To maintain proportions, it is enough to use information about the volumetric ratio from the second column.

Two words about the cost of concrete for the foundation

The work of preparing concrete mortar for pouring the foundation has always been very difficult and quite monotonous. Even with a 100-liter electric mixer, pouring, for example, the foundation of a 6x6 house, 120 cm deep, will require at least 15 cubic meters of concrete. In this case, it is necessary to deliver almost a hundred 50-kilogram bags of cement to the construction site, maintain the proportions and mix the mixture.

If we take the price of the ingredients cement - 150 rubles per package, sand - 500 rubles and crushed stone -700 rubles per ton, in this case the cost of a cubic meter of concrete for the foundation according to the proportions of cement, sand and crushed stone 1-3-5 will be just over a thousand rubles. Purchasing concrete from a construction organization will cost at least 2 thousand rubles. The difference is 15 thousand for hard work and a guarantee of exact compliance with the proportions of concrete, and therefore the quality of the foundation.

For large volumes of foundation pouring, it is still better to buy a ready-made solution. The question of the quality and proportions of concrete remains open. It is possible to study the quality of a sample only in a laboratory; moreover, the design strength of the foundation casting occurs only after 28 days, so the issue of compliance with proportions can be objectively assessed at the level of indirect signs.

For example, you can determine the nature of the plasticity of a concrete solution using the method given below. To do this, you will need a small container, the dimensions of which are shown in the figure. It is enough to fill the form with concrete and turn it over onto a flat surface. a metal sheet. The quality of the material can be judged by the degree of spreading.

The second option is to check compliance with the proportions and grade of concrete after the foundation casting has reached the design strength and hardness. If you try to prick the surface of the sample by hitting a chisel with a hammer, a mark no more than 5 mm deep will remain on ordinary M200 concrete, subject to the proportions and quality of the cement.

Just like many years ago, it is impossible to imagine any building without a concrete base. This applies even to small wooden buildings, such as a bathhouse. For your own house or the same bathhouse, you can make the foundation yourself. But in order for it to be durable, strong and last for many years, first of all, you need to know the proportions when preparing concrete for the foundation.

Main nuances

If you are going to start preparing concrete yourself, then initially you need to carefully understand such issues as:

1. Brand. Each brand of concrete mixture is designed for specific loads. They differ in strength and quality.
2. Depending on the brand, the requirements for the components included in each brand are different. You also need to know them.
3. Decide on the goal and select the optimal proportions for preparing, for example, the foundation for the foundation of any building.

This information will be useful to anyone. If you yourself are not going to prepare the building mixture, knowledge about specific brands and their components will definitely be useful to you. This will help make the choice easier and make it right.

But it should be noted that preparing the concrete mixture yourself is much more profitable than ordering it from a factory, and if you need a foundation for a small fence or bathhouse, then preparing the mixture yourself will be much cheaper. In some cases, you can even do without a concrete mixer and prepare the solution manually.

The most important thing is to correctly determine the required proportions when preparing concrete. If you need a small volume of the mixture, you can mix it with a regular shovel. But, if we are talking about pouring a foundation for a house or bathhouse or a strip-type foundation for a fence, then it is better to buy a concrete mixer. Currently available in stores big choice of this technique, which differs in capacity. Therefore, pick up best option It’s not difficult, and this technique will always come in handy.

Component Selection

So, the concrete mixture includes four components: sand, water, crushed stone and cement. Water is a binder, thanks to which the mixture becomes homogeneous and acquires the necessary thickness.

Separately, crushed stone should be highlighted. Sometimes it is permissible to use gravel instead, but the requirements for it are different. Gravel should consist of various fractions. If the gravel mixture includes flat and wide stones, then their total amount should not exceed 10% of the total volume of material. The gravel should not contain any foreign additives or impurities. All this will subsequently negatively affect the strength of the concrete foundation itself.

Not only for gravel, but for each component, there are a certain number of requirements. For example, the most ideal sand for preparing a solution is river sand. It is desirable that its particles are large. The use of sand mixed with clay is excluded. The last component leads to a complete loss of strength. Clay, which is part of the sand, and then the mixture, makes the solution greasy. Its ability to swell greatly under the influence of water, and then, on the contrary, to quickly shrink, leads to the fact that cracks often appear on the surface of the foundation even before it has completely hardened. A large number of clay may even contribute to the fact that the finished monolithic design will fall to pieces.

As for crushed stone, the fraction size should be 1-2 cm; this is the most optimal option. In addition, the material must also be clean and free of foreign impurities.

And, perhaps, the most important component is cement. People who have never encountered construction often make a common mistake, believing that if more cement is added to the solution, it will only become stronger. Actually this is not true. That is why the proportions established by GOST should be observed when preparing concrete. Excess cement can cause a monolithic structure to simply fall apart into pieces.

The amount of cement depends primarily on what you are going to make from concrete. When it comes to foundations, the most commonly used cement grade is M 500.

And the last component of the solution is, of course, water. It must be clean. It is unacceptable to use water containing various impurities or particles of paint, oil, or gasoline. This will lead to delamination of concrete and deterioration of its strength qualities.

Preparation of concrete

Not only the quality of materials determines the strength and quality of the concrete itself. You also need to know how to mix concrete and what procedure to follow.

If you use a concrete mixer, you must first start it and gradually add the components of the mixture.

1. First, a small amount of water is fed into the device, into which cement is added and mixed until smooth.
2. When the solution has become a uniform consistency, sand is added to it. You cannot pour out the sand all at once; this must be done in small batches.
3. When the mixture becomes homogeneous while stirring, you can add crushed stone and the remaining water. Each material must be added to the mixture in small batches and wait until the solution becomes homogeneous; you also need to add water.

A large amount of water means that the resulting liquid solution will have less strength. But too little water will in turn lead to more thickness. Such concrete is difficult to pour into formwork and level. Plus, if it's not mixed well, it can separate.

Of course, the question immediately arises: what are the most optimal proportions for concrete? The ratio should be as follows: cement: sand: crushed stone – 1:3:5. that is, for 1 kg of cement there are 3 kg of sand and 5 kg of crushed stone. These are the basic proportions for preparing concrete, which are used in private individual construction when laying the foundation. If we talk about the ratio of cement and water, it varies between 0.4-0.7.

Concrete grades

Calculations for various types concrete will be slightly different, depending on the required grade. Grades of ready-mixed concrete M 150, 200 are much less durable than M 450.

Let's consider the number of components for preparing different grades of concrete.

• Concrete M 100 – 1:5.8:6.1 (cement: sand: crushed stone);
• Concrete M 200 – 1:3.5:5.6 (cement: sand: crushed stone);
• Concrete M 300 – 1:2.4:4.3 (cement: sand: crushed stone);
• Concrete M 400 – 1:1.6:3.2 (cement: sand: crushed stone);
• Concrete M 450 – 1:1.4:2.9 (cement: sand: crushed stone).

If you carefully review the components, you can identify a certain trend in which to obtain a high grade of concrete, the proportions of sand and gravel should be smaller in relation to the amount of cement.

To prepare a mortar for the foundation, it is best to use the m 500 grade of cement. In addition to the ratio of quality components, it should also be taken into account that the prepared concrete mortar cannot be stored. It must be applied within two hours. If the foundation pouring work is carried out in winter time or for more low temperatures than in summer it is necessary to use warm water to eliminate the possibility of early hardening of concrete.

Experts recommend using special additives when building a foundation in winter, which are added directly to the solution; this is done in order to maximally preserve the properties of concrete, which depend not only on the correct proportion of sand and concrete.

Professionals recommend pouring the foundation only in the warm season, which significantly reduces your own labor costs and saves time. To lay a foundation in winter, it is necessary not only to use warm water and special additives. The concrete itself, directly poured into the formwork, will also have to be heated. At subzero temperatures, water freezes. It will also set in the concrete solution, which will lead to it turning into ice, swelling and causing the destruction of the foundation.

In addition, experts recommend maintaining the proportions of concrete in buckets for convenience. For example, to prepare a solution, take 2 buckets of cement, 2 buckets of crushed stone and 6 buckets of sand. Concrete prepared in the correct ratio will have all the strength characteristics.

The composition of the foundation is not only the presence of all the required elements, but also the selection of appropriate concrete for pouring. Its proportions and calculation of the volume for the foundation will vary greatly for each foundation for the house.

For the foundation, you should take cement of a grade not lower than M200.

Today they apply Various types foundations, among them it is necessary to highlight the structures of slab, pile, and strip foundations. Sometimes combined options are used.

What should be the composition of the strip foundation?

The most commonly used construction is a strip foundation, which is simple and economical. This design consists of a shallow concrete strip, which is installed around the perimeter and under the load-bearing walls of the house.

In some cases, ready-made concrete blocks and bricks can be used for it. In this case, the duration of work does not depend on the curing time; only the time for drying of the masonry mortar is taken into account. But for its preparation it is also required.

Pie for strip base home includes:

• sand and gravel cushion at the bottom of the trench;
• removable formwork from a regular edged board (removed after the concrete has hardened);
• concrete strip running along the perimeter and under the load-bearing walls;
• waterproofing the upper part of the strip foundation.

In production, such a foundation is considered one of the simplest; it can be erected on almost any type of soil.

To calculate the material, you only need to know the belt parameters such as height, width and total length. In some cases, the foundation is reinforced before pouring with metal reinforcing bars, which increases its strength and load-bearing capacity.

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What does a pile foundation include?

A pile foundation for a house consists of a foundation in the form of special support pillars. This option is used when building on difficult soils, on slopes, on swampy or sandy soils. In this case, the house exerts uniform loads on the ground due to the features of this design.

To prepare such a base you don’t need much; the design cake consists of the following elements:

• sand and gravel cushion at the bottom of the well;
• support pillars, which are filled with concrete after installation;
• for grillages, a special belt is used, which is used as a base for the house.

There is a variety pile foundation, which is a combination of strip and support (partitions are erected between the pillars to a small height). It doesn't take much time to prepare.

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Slab foundation and its composition

The slab type of foundation for a house is a foundation that is a monolithic, reinforced slab made of concrete. The recipe for such a base is simple, but very reliable. Pie slab base includes:

• base made of sand and gravel;
• slab (can be of several types: regular solid, lattice);
• waterproofing on the top.

The slab itself is reinforced using special metal reinforcement. may include reinforcing polymer additives that increase strength and resistance to various loads. But there are also disadvantages here. To lay the foundation you need high consumption materials. In addition, when building a slab base, it is impossible to build an underground garage or a spacious basement.

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Concrete for foundation: application features

To construct the foundation, concrete of various grades is used in a variety of proportions. Everything here depends on the type of foundation itself and the requirements placed on it. One of the most important issues at are the proportions of the ingredients. When choosing what the concrete composition will be for the construction of a monolithic slab, pile (columnar), strip foundation, the following features must be taken into account:

1. must exactly correspond to the expected loads and construction conditions. In this case, the structure will be strong and very reliable.
2. The foundation for a house can be of various designs (slab, pile or strip). To arrange it, blocks, support pillars or a liquid mixture for pouring can be used. But in any case, it is recommended to use only factory-made concrete mixtures that are of high quality. It is not recommended to make slabs or pillars from dry mixture at home.
3. The composition of concrete includes: cement of the selected brand, fillers (gravel or crushed stone, sand, granite sand), water. Plasticizers and special reinforcing additives are often used. The proportions of such a mixture depend on what cement will be used and what brand of concrete should be obtained in the end.
4. For the foundation it is necessary to take cement, the grade of which is no less than M200.
5. The strength of the concrete mixture for the foundation largely depends not only on the correct proportion, but also on the quality of the fillers. It is recommended to use different-grained materials that will evenly fill all voids.
6. After preparation, concrete can only be used for two hours, after which it begins to dry and lose its quality.
7. Water plays a big role in preparing concrete. The mixture should not be too thin or too thick; its consistency should resemble thick sour cream.

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Composition of concrete mixtures for foundations

The composition of concrete, as already mentioned, includes components such as gravel, sand and water. The base takes on the loads from the structure, so it is very important to take into account all factors when calculating the mixture. The proportions will differ depending on what brand of concrete will be used. For example, to build a house, you need to use concrete grades from M200, but for ordinary garden paths M100 is also perfect.

Let's consider the proportions and volumetric composition of concrete for various grades:

1. M200, mass composition - cement 1 kg, sand 2.8 kg, crushed stone 4.8 kg, volumetric composition for every 10 liters of concrete (sand/crushed stone) - 25:42, amount of concrete for every 10 liters of cement - 54 liters.
2. M250, mass composition - cement 1 kg, sand 2.1 kg, crushed stone 3.9 kg, volumetric composition for every 10 liters of solution (sand/crushed stone) - 19:34, amount of concrete for every 10 liters of cement - 43 liters.
3. M400, mass composition - cement 1 kg, sand 1.1 kg, crushed stone 2.5 kg, volumetric composition for every 10 liters of solution (sand/crushed stone) - 11:24, amount of concrete for every 10 liters of cement - 31 liters.
4. M450, mass composition - cement 1 kg, sand 2.8 kg, crushed stone 4.8 kg, volumetric composition for every 10 liters of solution (sand/crushed stone) - 10:22, amount of concrete for every 10 liters of cement - 29 liters.

The higher the grade of concrete for the mixture, the large quantity cement will be contained in the composition. Therefore, it is important to correctly determine which brand is needed in order to. The optimal ones are M300 and M400, which are quite enough to build a foundation even for a massive country house.