Brand of concrete for strip foundation: choice depending on the weight of the building and soil characteristics. What concrete to use for a strip foundation What concrete is needed for a foundation

The process of building any house is a very responsible process that requires careful selection of building materials. The construction of a house begins with the construction of the foundation. But each building requires its own cement. If the choice of this component is not taken seriously, then as a result your structure will be constantly subject to deformation and will not last long.

The role of the foundation is precisely to take on the entire weight of the house, so the key requirement for the foundation is strength.

Required brand

When you construct a building according to a pre-prepared engineering project, it already contains all the necessary materials to carry out all the work. In this case, there can be no hesitation. The project contains information regarding the grade of concrete for the foundations and other properties of the concrete mixture.

You can learn how to make geopolymer concrete from

The characteristics of concrete include mobility of the material, frost resistance and water resistance. But there are cases when the construction of a house is carried out from scratch. In this case, it is important to correctly determine the grade of concrete for a single-story and multi-story building.

You can read about the use of contact concrete from this

In addition, the choice of material is influenced by factors such as the type of terrain on which the house will be built.

The video explains what kind of concrete is needed for the foundation of a house:

How to determine the grade of concrete that will be needed for a strip foundation is described

Brand for a one-story house

A one-story building can be erected on a strip, columnar, pile or monolithic foundation. When choosing the required option, you must be guided by the specific operating conditions of the house. For example, the main criterion for choosing the type of foundation is the composition of the soil in the selected area.

To obtain the required solution you need to take the following components for preparation:

• cement – ​​1 part;
• sand – 3.5 parts;
• gravel – 5.7.

Thus, you need to take all the components in the following proportion: 1: 3.5: 5.7. If you are going to build a cottage, then you need to use concrete grade M200 and higher. To prepare such a solution, use the following proportion: 1: 2.5: 4.5. Thus, for 1 part of the binding component it is necessary to add 2.5 parts of sand and 4.5 parts of crushed stone.

For the construction of a multi-storey building, M300 grade concrete is often used. In this case, the concrete preparation process uses the following proportion: 1: 3.5: 5.6. Thus, one part of cement will require 3.5 parts of sand and 5.6 parts of gravel.

You can read about the types of concrete and their use

When M400 concrete is used, the process of preparing the solution should be carried out according to the following proportion: one part cement, 2 parts sand and 6 parts crushed stone. The figures given are averages, but all the indicated proportions must still be observed. Proportions always depend on the time of year. In our article you can read about the features.

But to prepare the solution, you need to know the amount of water added. Make sure that its volume does not exceed 0.65-0.7 parts of cement. In this case, you need to use clean water, preferably from a well. Never use salty liquid. Because it contains salt, metal surfaces will corrode.

Concrete is a very important component when constructing the foundation for a residential building. Today there is a wide range of finished products on sale, in which all the components are already mixed in the required proportions. But most often people use separate components to prepare a solution. If your choice is to make it yourself, then be sure to use high-quality materials, otherwise you will not be able to achieve a durable design.

As you know, the durability and strength of any structure depends on the quality of the foundation on which it is based. In private construction, as a rule, 3 types of structures are used: columnar or pile, slab and the most common strip, which we will talk about. The grade of concrete for the strip foundation of a private house is the most important indicator of its quality.

What is a strip foundation?

The strip type of foundation structures is considered the most common.

It is a reinforced concrete strip buried in the ground and passing in a closed loop under all load-bearing walls and piers of the building.

• The instructions for arranging this type of structure are not very difficult.. A trench is dug, a reinforcing iron frame is laid in it, and the whole thing is filled with liquid concrete.
• But, despite the apparent simplicity, perhaps the most difficult point here is the correct determination of which brand of concrete to use for a strip foundation. This choice is influenced by a number of components.

What factors influence the choice of composition brand?

Unfortunately, there are no universal recipes; price is not always a fundamental factor. After all, even expensive formulations have their own recommendations and restrictions on use.

Dependence on the weight of the building

If you want to build a house with your own hands, but you do not have a ready-made project with prescribed recommendations, then, first of all, you should pay attention to the total weight of the building. This is the first indicator from which to start when selecting a brand of composition.

• A prefabricated panel house with a height of 2 floors, in most of our country, will comfortably stand on a reinforced concrete foundation poured with the M200 grade.
• For 2 - 3 storey log buildings, as well as for houses built from foam concrete, gas silicate blocks or other cellular concrete, grades M200 - M300 are recommended.
• For heavy, permanent buildings built from brick, solid concrete structures or other heavy materials, it is recommended to use a grade of M300 and higher.

Soil characteristics

Much depends on the geology of the soil in a given area, its composition and how deep the groundwater lies.

• Sandstones and rocks are considered the most favorable. They can be poured with concrete M200 - M250.

• Clay soils and loams pose quite a big problem. The fact is that these soils are susceptible to heaving when they freeze. That is, they do not freeze evenly and are capable of squeezing out the shallowly buried strip foundation in some places, which leads to general deformation.
  In this case, you can do it in two ways.

• First, deepen the structure to a level exceeding the average rate of general soil freezing in a given region.
• Secondly, you can build a strip-column, well-reinforced foundation. This is when at key points they are poured to a significant depth, which stabilizes the entire structure.
• If we talk about what brand of concrete is needed for a strip foundation laid on clay, then experts recommend taking a grade that is an order of magnitude higher, approximately M250 - M300.

Important: it should also be taken into account that starting from grade M200, if necessary, cutting of reinforced concrete with diamond wheels is already used, and for deepening, diamond drilling of holes in concrete is used.

Common grades of concrete

When producing different grades of concrete for foundations, M 400 cement is most often used, but in different proportions.

• M100 - used as an underlayment when building roads, laying deep foundations or pouring floor screeds.
• M200 – suitable for shallow foundations based on stable soils. It is used to fill basements and various open areas.
• M250 – used for casting fences, various kinds of stairs and strip-column structures.
• M300 is considered the most popular brand for pouring foundations. It can be successfully poured into the vast majority of known foundation structures and can be used in damp environments.
• M400 - used for pouring underwater structures, bridges and other permanent structures. Used for building houses in extreme conditions.
• M500 - used for pouring vertical structures, repairing roads and structures, or as an additive.

Important: the quality and strength of concrete is greatly influenced by the so-called shrinkage coefficient - the lower it is, the stronger the structure will be.
It can be reduced using special additives.
When using vibrating machines, harder and drier compounds can be poured.

What else is worth paying attention to

• There is also a marking characterizing the strength class of the hardened composition. It is designated by the letter “B”, characterizes the compressive strength margin and is measured in megapascals.

Important: the strength of concrete can change over time.
Active strength gain occurs within 28 days from the moment of pouring.
Further, these processes slow down significantly, but do not stop.

• The strength level and grade of concrete are related indicators.
  According to GOST, each brand of concrete corresponds to its own, here are some basic indicators:

• B7.5 corresponds to M100
• B15 corresponds to M200
• B20 corresponds to M250
• B22.5 corresponds to M300
• B25, B27.5 correspond to M350
• B30 corresponds to M400
• B35 corresponds to M450

• For our country, the frost resistance indicator is also relevant; it is marked with the letter “F” and a certain number after it. The number indicates how many times the structure can freeze. For a larger area of ​​the country, F200 is sufficient; the more thaws in winter, the higher this figure.
  
• It is also worth paying attention to the indicator of resistance to high humidity. It is indicated by the letter “W” and the number after it.

Conclusion

It is worth considering the fact that the higher the class, quality and of course the price of concrete, the faster it will set. Experts advise pouring high-quality compounds within 1 day. Accordingly, quickly pouring such a foundation with your own hands will be problematic, so here it is better to resort to the services of construction companies. You can find more information in the video posted in this article.

When starting any construction, the need arises to select materials for the foundation. Many questions arise. What concrete is best to use for construction? What characteristics should it have? How to choose the right brand?

What factors influence the choice of concrete for making a strip foundation?

In the construction of houses, strip foundations are the most popular. This is a strip of reinforced concrete that is laid across the entire area of ​​the future building. The tape is laid under all existing walls in the same shape.

There are two types of strip foundation:

• Recessed– when building brick houses, it is installed about 30 centimeters below the frost line. It is durable and resistant to deformation.
• Shallow– most often it is poured under wooden houses and buildings, as well as light structures. It is laid to a depth of no more than 70 centimeters. It is recommended to lay such a foundation in the warm season. The formwork is made from boards 50 mm thick, having previously cleaned them of dirt and moistened them with water. All boards are firmly fixed and measured with a plumb line for verticality. The formwork should protrude 30 cm or more above the ground surface.

To avoid compromising the integrity of the foundation, holes are left for water pipes. Along with the formwork, reinforced rods are installed. They are often mounted in two rows vertically. The frame is made along the entire height of the foundation, connecting the lower and upper parts together.

The rods can be secured with wire and also using a welding machine, but the second option cannot be done inside or near the formwork.

To ensure that there are no voids in the foundation, concrete is poured into the formwork in layers of 15 cm. It would be useful to use a concrete vibrator.

Not only the strength of the foundation, but also the safety of the building depends on the choice of concrete. Concrete is a hardening mixture consisting of four main components: cement and water, as well as fine and coarse aggregates.

Based on their saturation, there are three types of concrete:

1. Skinny- when the mass flows from the shovel. It contains many unnecessary additives, is convenient to use, but has very low strength.
2. Normal– the ratio of components meets all standards.
3. Fatty– contains too many binding components. This design is short-lived and tends to crack during use.

You can order a concrete solution of any brand with the correct ratio of sand, crushed stone, cement and water on the website Concrete 174.

Concrete grade

• Gives a characteristic of the compressive strength in kilograms and square centimeters. The types of concrete used for construction are:
  • M100;
  • M150;
  • M200;
  • M250;
  • M350;
  • M400;
  • M450;
  • M550;
  • M600;
  • M600;
  • M700;
  • M800.
• The brand is tested for frost resistance by alternating freezing and thawing. Concrete of this grade should not lose strength due to temperature changes.
  Frost-resistant brands include:
  • F100;
  • F150;
  • F200;
  • F300;
  • F400;
  • F500.
    The higher the number, the more freezing and defrosting cycles the concrete will withstand.
• Water resistance is the property of a concrete mixture not to deteriorate with frequent contact with moisture.
  Based on water resistance, concrete is divided into grades W2, W4, W6, W8 and W12. The brand indicates what water pressure is per kilogram squared. The number next to the letter is an indicator of how much water will pass through the concrete.

In addition to grades, concrete is divided into classes.

Concrete class

This is a characteristic of its properties.

There are the following classes of concrete:

• B1.5;
• B2.5;
• B3.5;
• B7.5;
• B12.5;

The class differs from the brand only in that it indicates guaranteed strength, while the brand only has approximate strength.

External factors when choosing concrete for the foundation

Before you start laying, you should choose the most suitable brand of concrete, taking into account all the nuances associated with the quality of the necessary materials and external factors:

What is needed to make concrete?

The concrete mixture consists of four components:

• cement;
• sand;
• crushed stone;
• water.

Cement and water are the main components of concrete. Their function is to connect all components into a homogeneous structure. Maintaining the correct proportion of all components when making concrete is the main task.

Manufacturing methods differ in the ratio of components, brand of cement, various additives and fillers.

When making concrete mass, the mixture decreases in volume. One cube yields 0.71 m³ of concrete.
Another factor that can affect strength is the appropriate proportion of sand, cement, and crushed stone. Their proportion should be approximately 5: 1: 3. Sometimes crushed stone is replaced with gravel.

The strip foundation is prepared directly on the work site.

To prepare the solution for the foundation you will need:

1. Sand;
2. Water;
3. Crushed stone;
4. Cement;
5. Capacity;
6. Shovel;
7. Concrete mixer;
8. Reinforced rods.

The required grade of concrete is selected based on strength. The brand itself indicates what load should be per 1 cm². The load measurement is calculated in kilograms. If the brand is M350, it can withstand a load of 350 kg per 1 cm². When choosing, the weight of the building as a whole, the soil, and the presence of a basement are taken into account.

To fill such a foundation, a cushion of sand and gravel is made. If the building does not have much weight, then such a pillow is not necessary.

Influence of ingredients on concrete quality

The quality of concrete largely depends on what ingredients are used.

The more foreign additives they contain, the lower the quality and strength of concrete:

• Sand– this is a natural material, with a grain size of 0.1-5mm. Many types of sand are used in construction. They differ from each other in grain size and the presence of various impurities. There are two types of sand most commonly used:
  • Quarry sand contains many unnecessary impurities, there is a need for sifting, washing and drying.
  • river sand more suitable for use, since it has almost no additives.
• Water for concrete must not have any foreign additives or contain chlorine or salts. Fresh water should be used to prepare the solution.
• Crushed stone consists of small pebbles of various shapes. The rough surface and sharp corners of the crushed stone contribute to a better binding of the solution ingredients.
• Cement, included in the concrete solution, is used to bind all other components and has the property of hardening very quickly. Therefore, it is recommended to use a fresh solution no later than an hour or two. You need to buy high quality cement from trusted manufacturers. For private buildings, it is best to choose grade 300 or 400. Cement has the ability to absorb moisture, so it is not recommended to store it for a long time.

Sequence of adding components

When making concrete mortar, two methods are used:

• mechanical;
• manual.

These two methods differ in the sequence of adding components.

The mechanical method is used if a large amount of concrete is required.

In order to prepare the mixture, you need:

1. A place with a flat surface where the concrete mixer will be placed;
2. Lubricate all blades and walls apparatus with a mixture of water, cement and sand;
3. Turn on the concrete mixer;
4. Next step– pour half of the prepared water;
5. Place half prepared crushed stone;
6. Wait up to five minutes while these components are mixed;
7. Add cement;
8. In a few minutes add sand;
9. Add the remaining crushed stone;
10. Gradually pour out the remaining water into the concrete mixer;
11. Wait until the solution will acquire the desired consistency.

If the solution is prepared manually, the sequence is completely different:

1. Preparation special container;
2. Preparation buckets, shovels, watering cans;
3. Mixing crushed stone and sand in a container prepared in advance;
4. Add cement;
5. Mix the ingredients;
6. Make a well in the mixture and add some water;
7. Mix until smooth;
8. Add the rest of the water;
9. Mix thoroughly until you get the desired mass.

Mobility of concrete

Denoted by the letter “P” in combination with a coefficient of numbers from 1–5. This designation carries information about what the sediment of the solution cone should be at a certain value. That is, it informs about the fluidity of concrete.
The lower the number coefficient, the greater the density of the concrete mass.

For the foundation of private buildings, P-2 and P-3 are most often used. Concrete with greater mobility is recommended to be used only when it is planned to pour a foundation on a reinforced base.

Based on the indicators of the level of plasticity, the material is divided into two groups:

1. Sedentary rigid mixtures. They contain a small amount of water and without external influence they are not able to fill the mold. These include compositions P-2, P-3. For high-quality installation, vibrating equipment is used to remove voids in the monolith. During winter construction, it is recommended to heat the solution.
2. Liquid mixtures of high mobility. Their indicator is P-4 and P-5. They are usually used when pouring formwork, constructing columns and reinforced products. To determine the mobility of the mixture, you need a cone up to 30 cm high in which the solution is placed. The amount of solution in the container should not exceed six liters.
   The check is carried out in several stages:
   1. Filling the cone with the mixture.
   2. The solution is punctured to get rid of voids.
   3. The container is removed from the solution and placed nearby.
   4. Elasticity testing is carried out.
   5. Concrete subsidence of up to five centimeters means that the concrete is hard.
   6. If the drawdown is greater, it means that such a mixture has increased mobility.

What determines the reliability of the foundation?

In order for the foundation to be strong, you should pay attention to the correct selection of type, design, quality of materials used, technology for preparing concrete mortar and pouring it.

There are seven types of foundation:

1. Tape– made according to the thickness of the wall, but not less than 50 cm. Used in the construction of brick houses. It is laid below the ground freezing line.
2. Columnar– pillars are poured along the entire perimeter, where the corners and walls of the future house should be located. Such a foundation is placed exclusively on motionless soils. Unlike a strip one, you cannot create a basement in it.
3. Pile– designed for construction on unstable ground. Mostly large buildings are built on this basis.
4. Monolithic- used for wooden houses when there is strong soil compression.
5. Screw– used on complex landscapes with high groundwater levels.
6. Tiled– is a subtype of monolithic foundation. Its base can also serve as a floor.
7. Floating– this type of foundation may be suitable only if the groundwater level in the area is low or if there is heavy soil. Perfectly protects the building from destruction due to soil deformation.

The foundation must also have:

• Great durability. The service life directly depends on this;
• The presence of holes for ventilation to avoid troubles such as dampness or mold;
• Waterproofing, which will further protect the foundation from the influence of groundwater.

Note: When purchasing cement, you need to pay attention to the expiration date and production time. In autumn and winter, pure material is produced much less frequently than in the spring and summer. Therefore, there is a high probability of purchasing expired goods.

The shelf life of cement is one month. After this period, the material loses from 10 to 30% of its qualities.

Monolithic foundation slabs are included in the class of non-buried foundations. Concrete is poured into a pit, along the perimeter of which formwork is placed, with a reinforcement cage installed, on a compacted sand and crushed stone cushion. The height of the slab is from 0.2 m. A base of this type can be used on various soils. This is an excellent option on unstable soils. In order for the constructed foundation to last as long as possible, to be strong and reliable, it is necessary to select the appropriate grade of concrete for the slab foundation. There are a number of factors to consider when making your choice. Material and labor costs will depend on its correctness.

Features of a slab foundation

The foundation slab is used mainly in areas with problematic, unstable soils, in places where groundwater is close to the surface. Also, such a base is used when there is a risk of landslides or on bulk soils.

The technology for creating a monolithic slab is implemented in several stages:

• conduct a geodetic survey of the construction site;
• dig a pit of the required depth;
• lay out the formwork;
• the bottom of the excavation is covered with a sand-crushed stone cushion, the thickness of which varies from 0.1 to 0.3 m;
• knit reinforcement in two rows;
• fill the form with concrete.

A slab-type foundation is also called “floating” because it can withstand quite significant ground movements without affecting the construction. Also, such a foundation allows the construction of multi-story, heavy buildings.

The large consumption of building materials, and therefore money, for the implementation of the project in practice is considered the main disadvantage of a monolithic foundation. Construction work is also accompanied by greater labor costs compared to the creation of other types of foundations.

Choosing the highest grade of concrete will provide a high-quality result in terms of reliability, strength and durability, but financial costs will increase significantly. In most cases, this will not be justified from the point of view of the existing loads, therefore, in each specific case, the choice of concrete grade should be approached taking into account the factors acting on the foundation being constructed.

Classification of concrete

The main components of concrete are cement, water, filler and various additives. The first serves as a binder, with the help of which other constituent elements are connected.

The following materials can be used as fillers:

• gravel;
• sand;
• crushed stone;
• various bulk substances.

Fillers are designed to reduce internal stress in concrete as it gains strength (hardening).

The final strength of the monolith depends on the presence of water in the required proportion in the solution. Excessive amount of liquid leads to mechanical weakening of the created structure.

Concrete is classified according to the criteria given in the table below.

It is recommended to use compounds with an increased degree of frost resistance to avoid the appearance of cracks after several years due to temperature changes. The range of parameter values ​​is from F25 to F1000. Frost resistance is an important parameter on very wet soils, where there is constant contact of the supporting structure with the soil.

The value of the water resistance coefficient ranges from 2 to 20. When constructing the foundation, choose W2 - W12, focusing on the groundwater level.

The final quality of the pour is determined by many factors. One of the main ones is the correct ratio of incoming components. High quality material should be used.

Concrete grades

The grade of concrete determines the construction area in which it can be used. It shows how a foundation that has gained full strength will resist operating loads. The brand is the main characteristic when choosing a building material; its strength is shown in kgf/cm2. At the same time, water resistance and mobility are reduced.

Among the existing grades of concrete (from M50 to M1000), M100-M450 have gained practical distribution.

The table below shows the grades of material and their characteristics.

Due to its high cost, the M500 is not popular. The most widely used concrete grade among private developers is M350. It is the best option in terms of the price of the material and its quality.

Factors determining the choice of concrete for a monolithic slab

When building lightweight structures on a slab, such as a garage, gazebo, barn, small frame or wooden house, the foundation material can be selected with an approximate consideration of the existing loads. Concrete grades M200 and M250 are suitable. Very rarely a slab foundation is made for light structures. Often they make do with pile or columnar types of foundation.

To choose which concrete is best suited for creating a reinforced monolithic slab in a particular case when constructing heavier buildings, it is necessary to analyze a number of factors:

• geological conditions at the construction site: soil type, its structure, groundwater level;
• climatic features of the region: temperature regime and degree of air humidity;
• the weight of the building being erected and associated loads from snow, furniture, residents, household appliances and equipment.

All the factors considered must be taken into account in order to correctly determine the appropriate brand of concrete. Independent construction of the foundation (the entire structure) requires certain knowledge and practical skills in performing the work.

If the necessary experience is not available, then it is better to use the services of specialists who will not only competently construct the object, but also select the material suitable for specific conditions.

Concrete grades for creating a monolithic slab

In hard, rocky and sandy types of soil, the entire load from the structure is distributed evenly. To build lightweight buildings on them, you can use concrete grade M150 or M200. Heavier buildings will require the use of M300 or M350.

Clay soil is characterized by a high degree of heaving; its volume increases greatly when it freezes unevenly in different directions. In this case, only the M350 - M450 varieties are suitable.

On any soil, the heavier the building being erected, the higher should be the grade of concrete used to build the foundation for it.

In most cases, to pour a monolithic slab foundation, you can use concrete with the following performance characteristics:

• from F200 degree of frost resistance;
• mobility P-3;
• waterproof coefficient value, starting from W8;
• brand M300;
• class B22.5.

If the soil moisture on the building site is high or groundwater lies close to the surface, then special attention should be paid to the waterproofness of the concrete. Proper waterproofing of the base from below and on the sides will also help solve the problem. When choosing a method to protect a foundation from water, economic feasibility is often the deciding factor. It is often cheaper to use waterproofing materials than waterproof varieties of concrete.

Ready-made mixtures offered by construction retail chains contain the ingredients in the required proportions. You just need to mix them in the right ratio with water. The marking of the finished mixture is determined by the quality of the materials included in its composition: the grade of cement, the size and strength of crushed stone and sand particles.

If you mix M400 cement, crushed stone and sand in a ratio of 1:4:2 with water (50%), you will get concrete marked M250. If you add the binding component M500, then the grade of the final material will be M350.

During the production of a mixture in a factory, many related factors are taken into account when applying markings to products. At home, the best option is often to use M300 compounds that have the recommended parameters of frost resistance, mobility, and water resistance.

Calculation of the required volume of material for pouring the foundation

To determine the amount of concrete required for constructing a slab, you need to know its volume. It is found by multiplying the height by the width and length or by the area of ​​the base.

The table below, according to GOST 7473-94, shows the correspondence of the class of concrete to its brand and the consumption of cement (M400) with a certain frost resistance, water resistance, mobility per 1 cubic meter of solution along with crushed stone, sand and water.

Knowing the volume of the slab, using the table you can determine the required amount of sand, crushed stone and cement to fill the foundation with the required strength. You can easily prepare the working mixture in the indicated proportions yourself.

The technology for constructing a slab foundation is presented in the video below.

Recommendations for choosing crushed stone, sand and concrete grade for constructing the foundation are given in the video below.

The correct choice of concrete grade used for the construction of a slab foundation will determine the service life, reliability and strength of the entire structure. The choice of material is determined by the geology of the site and the mass of the future building. Products with the required parameters can be purchased in the form of ready-made mixtures or prepared independently.

It is worth noting that no matter what type of foundation the owner of a country house chooses, he will always have the question of what type of concrete to choose for this very foundation and how the characteristics of concrete differ from each other.

Concrete composition

Any concrete includes 3 fundamental components - these are:

1. Cement- a component that binds other fillers.
2. Fillers— Crushed stone, gravel, sand, various bulk additives.
3. And directly water.

As a result of the synthesis of these groups of components, concrete is formed; it is worth noting that the quality of concrete directly depends on the percentage of our fillers in the cement. Fillers are used in order to reduce the stress of concrete as a result of hardening of the foundation, and in order to reduce the economic cost of the structure, since the cost of the building directly depends on the choice of concrete components.

Concrete marking

1. M - concrete grade.
2. B - concrete class.
3. F - concrete resistance to frost.
4. W - characteristics of concrete water resistance.
5. P - mobility of concrete.

Concrete grade

Concrete grade- a fundamental characteristic that shows us how a frozen foundation will transfer compressive loads after its hardening process, that is, after 30 days.

Concrete M100 B7.5 — Concrete of very low quality is mainly used in preparatory work during construction for pouring concrete pads under the foundation.

Concrete M150 B12.5 — concrete of not very good quality is mainly used in the construction of concrete paths and rough screeds.

Concrete M200 B15 — This concrete is used for the construction of elements with low load, such as stairs or for pouring strip foundation slabs.

Concrete M300 B22.5 — The most popular brand of concrete in Russia, because the quality of this concrete can be rated at a strict 4! They are also used for the construction of good and high-quality country houses.

Concrete M350 B25 — high-quality concrete, which is used for the construction of concrete structures requiring extremely high strength.

Concrete M500 B40 — Quite rarely used in Russia, because concrete costs large investments; it is mainly used for the production of bank vaults or for the construction of special buildings. objects.

Concrete class

The concrete class is designated by the letter B and characterizes more detailed information about the degree of compression; we can see information about more accurate data above.

Mobility of concrete

Concrete mobility Letter P - an indicator that characterizes the liquid of a homogeneous concrete mixture and the flow coefficient. It is worth noting that even a slight excess of water in the composition of this concrete can result in a loss of strength, and as a result, major problems.

Waterproof

Water permeability - letter W. Characterizes the coefficient of water permeability of concrete by water, usually they range from 2 - the minimum value to 12 the maximum value. This coefficient should be taken into account if there is groundwater on your site and the foundation can “play” when flooded by ground underground sources. By the way, if you want to get rid of this problem, I recommend reading the article about and about, which will leave your foundation in perfect condition.

Frost resistance

Frost resistance letter F - an indicator that characterizes how much defrosting and freezing concrete is able to withstand.

Video - pouring a house with high-quality concrete