What you need for concrete with your own hands. How to prepare concrete at home proportions

Concrete manufacturing technology is a rather complicated process. Concrete is necessary for the construction of any buildings. It serves as the basis for the foundation of the premises, is used in the construction of the house and for the construction of roofs.

In addition, designers create masterpieces from concrete material, such as vases and decorative urns, block paving slabs or individual items for the interior.

In contact with

Classmates

Main characteristics of concrete

The modern composition of concrete makes it possible to compare it with granite and marble - very resistant natural materials. This is due to the fact that manufacturers use modern technologies in the process. However, the appearance and structure of concrete is not so beautiful. Designers have learned how to process its surface using the latest devices, allowing it to give it unique shapes. The undoubted advantage of concrete in construction is its non-radioactivity. Before construction, you can prepare the solution yourself at home, as well as purchase it at a building materials store. Having decided to prepare a concrete solution on your own, you should find out the constituent components and proportions of concrete in order to achieve a good consistency and improved performance in the future.

Structure and components of concrete

When making a concrete solution yourself, you need to know its components and their ratio. The solution is prepared in a specialized concrete mixing machine or in a conventional barrel or tub.

Note!

The cement composition is the basis and main component in the entire mortar.

It consists of several components:

limestone. As an ingredient, it interacts with water, forming crystals that harden and give strength to concrete.
a mixture of river sand and coarse gravel is a common ballast. Experts recommend mixing the components three to one.
special, used in construction. This component arises as a result of the impact of rivers, lakes and other water sources. Due to the fact that these grains are very small, they are round and smooth, which makes it easier to lay bricks and concrete slabs to the required level. The natural clay contained in the construction sand provides the viscosity of the concrete prepared in the correct proportion.
crushed stone formed as a result of crushing rocks. This component has a size of more than five millimeters.

Do-it-yourself concrete video:

Component ratio

In the manufacture of concrete mortar at home, it is necessary to strictly follow the instructions of specialists. To obtain a homogeneous and uniform structure, all the constituent ingredients of cement should be combined with water. When calculating the exact amount of liquid, it is important to take into account the characteristics of other materials used in construction. Each building material has its own absorbency.

The preparation of concrete depends mainly on a properly made mortar for construction. It is often used in finishing and other construction work, and helps in the construction of brick walls. To date, the mortar includes binders, usually cement and viscous clay, and a filling component. As a filler, sand taken from reservoirs, small wood shavings or unnecessary slag are used.

Proportions in the manufacture of concrete

The most common proportion of components is:

One unit of cement
Three units of river sand
Six units of additional filler.

In order to achieve a certain density of the solution, you need to know how to knead the concrete.

Note!

If you need a thinner solution, it is recommended to add half or one part of water to it.

However, in order to obtain concrete of the best possible structure that meets all state quality standards, special attention is paid to the exact proportions of the ingredients. The main factor in this is the density and basic characteristics of the cement slurry, the fill material used and the sand.

Additional additives in concrete

To improve the quality and performance characteristics, the concrete mortar is mixed with modern additives and components that are widely used in the building materials market. The creation of concrete at home depends on a number of factors, what characteristics need to be improved, you can add to it:

plasticizers. They are used to make concrete with your own hands comfortable and have plasticity for convenient laying.
hydraulic seals. This component is an insulator from excess moisture.
dedusters. They strengthen the concrete, preventing it from abrasion and cracking in the future.
grout accelerators or retarders regulate the setting time.
frost-resistant additives.

Before you purchase the necessary additives, you should pay attention to their characteristics. This is due to the fact that some components can have a complex effect on the solution. However, some additives do not combine with each other, so be sure to read the instructions for them before buying.

Mixing process

Concrete making tools and options

The most common option for where and how to mix concrete are various concrete mixers. By manual mixing in a bucket or barrel, it is impossible to achieve complete mixing of the solution to a homogeneous state. At the same time, at home it is problematic to stir large volumes of the solution, for example, to fill the foundation. When making concrete with your own hands, two options are used:

Initially, all dry components are combined, stirred, and only after that they are gradually filled with water. In this case, the materials are distributed fairly evenly, but at the same time, manual mixing and the gradual addition of water do not guarantee complete and rapid wetting of all components. In this regard, undissolved materials in a dry form may remain at the bottom of the barrel, and, consequently, the proportions of the preparation of the solution are violated and the concrete is of poor quality.
The second option involves pouring dry ingredients into already prepared and measured water. Then a long mixing of the solution is recommended so that the cement can adhere to other fillers and components.

ready concrete

concrete mixing

Conventional standard concrete mixers are designed for 200 liters of ready-made mortar. Accordingly, all proportions and the ratio of components will be calculated from this amount. How to make and mix concrete correctly:

Initially, a measured part of the water is poured into the mixer. About 20 percent is left in case to add it later.
Cement composition is poured into the water.
After filling the sand, everything should be mixed well until all components are evenly distributed for about 5 minutes.
After mixing, the necessary additional components are added to the finished cement mortar to enhance certain characteristics of concrete.
The last aggregate in the form of crushed stone or coarse gravel is poured into the concrete mixer.

The entire process of mixing concrete should take place within 10 minutes, until the mortar begins to harden and delaminate.

Concrete is a unique material. It is actively used in construction, but it can also be used to make piece products. Concrete mortar is a mixture of several components. Knowing the exact composition of the mixture and proportions, it will not be difficult to make concrete with your own hands. The quality of the resulting solution largely depends on the components used.

Main Ingredients

The main characteristic of concrete is compressive strength, measured in megapascals (MPa). It depends on the class of the material. Using special additives in certain proportions, making concrete with your own hands will be quite simple.

Cement and sand

The main component of concrete is cement, since it is he who binds all the other ingredients into a single mass. For the manufacture of concrete mortar, it is worth choosing Portland cements, which are characterized by a high content of calcium silicates. However, depending on the tasks to be solved, other types of cement can be used. For example, in the construction of private houses, brand 500 is most often used.

Portland cements not only have good adhesion, but also allow construction work to be carried out at low temperatures. However, in such a situation, special additives have to be used. If construction takes place in the warm season, then Portland slag cement should be used. When buying a material, it is necessary to pay attention to its flowability, and if the cement is damp, then it cannot be used.

Sand is the second important component for the manufacture of the material. It is desirable that this material has a fraction of 1.5-5 mm. The best choice would be river sand. Although it is more expensive than quarry, the particle sizes are excellent for the task at hand. If concrete is created for the construction of a foundation, then clay is allowed in the sand.

Crushed stone and gravel

It is thanks to these aggregates that concrete acquires its main strength. However, when choosing breeds, it is extremely important to take into account their characteristics. Often, expanded clay or other similar materials are used in construction. The size of crushed stone and gravel can be in the range of 8-35 mm. A larger breed is sometimes used in industrial construction, but quite rarely. To make good concrete with your own hands, you should use an aggregate containing particles of different sizes.

You can mix medium gravel with coarse gravel. This is due to the fact that home craftsmen do not always have a professional tool for compacting concrete. The presence of particles of different sizes in its composition will ensure their tighter fit. Also, during the preparation of concrete, attention should be paid to the choice of water, which should not contain acid or alkaline inclusions.

Special additives

Sometimes slaked lime is added to the concrete to make the mortar easier to lay. However, it should be remembered that this substance can prevent the cement from bonding normally with aggregates and the strength of the material in this situation will decrease. You can change the fluidity index of the solution using plasticizers. However, if concrete is planned to be used for pouring the foundation, these additives can be omitted.

Some admixtures make it possible to give concrete unique properties. For example, there are substances that accelerate the process of curing mortar in cold weather. To increase the reinforcement rate in construction, special additives are used. For example, when creating a thin screed, polyvinyl chloride or polypropylene fiber is added to the solution. These additives are quite soft, they are not very strong, but they allow you to avoid cracking of concrete.

Selection of ratios of components

The composition of the concrete solution depends on the tasks solved with its help. For example, when forming the foundation, you should use a durable material containing crushed stone of large sizes - 20-35 mm. However, such a solution must have a high fluidity so that air bubbles can be easily removed from it during tamping. According to the foundation manufacturing technology, the base material should be poured onto the substrate made of less durable concrete. For its manufacture, only a mixture of concrete and sand can be used.

To make concrete, the proportions of the components are most often 1:3:6 - cement, sand, crushed stone, respectively. Depending on the required fluidity of the material, 0.5-1 part of water is also used. Of course, such a solution is not always the best choice. It is best to carry out simple calculations in accordance with regulatory documents. In private construction, the most popular brands of cement are M-400 and M-500. Depending on the proportions of the main components used, it is possible to obtain the material of the required grade.

Concrete mixers are the best choice for mixing mortar. With their help, you can mix all the ingredients with high quality and as a result get a concrete solution of the desired quality. If the volume of construction work is small, then you can knead the solution manually. Thus, there are 2 ways to make a concrete mortar at home:

All components are pre-mixed in a dry state, and then water is added to them.
The remaining ingredients are added to the required amount of water.

In the first case, the dry substances are distributed evenly, but if the solution is kneaded by hand after adding water, its quality may not be the highest. The fact is that in such a situation it is difficult to achieve uniform wetting of the ingredients. The composition remaining at the bottom of the container will remain dry, and the proportions will be violated. Prolonged stirring is also not a good solution, as the solution may begin to set.

The second option is somewhat better, but it is still worth renting or purchasing a concrete mixer. This unit must be installed at a maximum distance of 40 m from the construction site. As a result, the prepared solution will not delaminate during mixing and delivery. It is quite obvious that all components must be located near the concrete mixer.

Mixing concrete

A conventional concrete mixer has a volume of 200 liters. When calculating the proportions of all ingredients, it is necessary to focus on this figure. The algorithm for making a solution is as follows:

On average, it takes about 10 minutes to prepare a portion of the solution.

Pouring solution

When the cement is prepared, it must be correctly poured and then distributed. This stage is no less important than the previous two. Since concrete is a heterogeneous mixture, it must be compacted after pouring. This allows not only to compact all the ingredients, but also to get rid of air bubbles. To solve this problem, special vibrators are used.

For compacting a thin layer of concrete, such as screeds, it is better to use surface vibrators. As a result, simultaneous leveling of the surface and compaction of the solution are achieved.

During pouring, it is extremely important to pierce the concrete to the full depth using a pointed rebar. This will get rid of the air that is not only in the concrete, but also in the reinforced mesh. The filling process is carried out in several stages and when adding a new layer, it is important to go at least 10 cm deep into the previous one. When the entire solution has been used, it remains only to level its upper level. It is allowed to perform these actions in several passes, as the solution dries.

If it is not possible to use professional equipment, all work must be done manually. For example, to compact the foundation, you can strike with a sledgehammer on the bars that hold the formwork together.

To ensure that the solution dries evenly, as well as to protect it from adverse external factors, it is covered with a film. The average drying time of concrete mortar is 36 hours. However, it is worth doing further work in seven days.

Concrete is a unique material due to its properties. It is used not only for construction work, but also for the construction of various structures and buildings. Many piece goods are also made from it, for example, such as: vases, balusters and even countertops for the living room, paths in the garden. Modern methods of manufacturing concrete and its further processing help it to be on a par with materials such as marble or granite. Although this material is not very aesthetic, unlike the latter, everyone has long known what it is made of.

If you decide not to buy concrete, then you need to find out how you can make this material yourself, so that it can meet the required qualities and will have excellent strength and long service life. Although the concrete manufacturing procedure is the simplest, it is necessary to take into account a number of some nuances and features that will determine its further quality and suitable properties. Depending on the main purposes for which this material is produced, its scope and formulation will also be changed.

What are the qualities of concrete

And if you wanted to learn how to make concrete with your own hands, then you must take into account the proportions. But before talking about the manufacturing process of this building material, it is necessary to find out what concrete is and what basic qualities it has.

Basically, concrete consists of a mixture of special filler and cement. Based on this, the most important ingredients of concrete are: sand, cement and filler. At what as a filler can be: pebbles, crushed stone, gravel and other solid materials. In modern technology for the manufacture of this composition, the use of some additives, such as plasticizers, is assumed. Their main purpose is to give concrete additional unique properties.

The most important properties of concrete should be compression and strength. The latter property is usually expressed in mega pascals (MPa). They determine the class of concrete, as well as the pressure. Depending on the strength, concrete is divided into the appropriate grades. In the CIS countries, according to the approved GOST, the classes have the following designation:

B7.5-B80. Their main difference depends on the type of cement that is used in the preparation of concrete.

(M300-M-600), as well as all kinds of fractions, sand, and crushed stone. The numbers in the class name, as a rule, indicate the pressure in MPa that the concrete will withstand in 96% of cases.

The simplest version of concrete is a simple mixture of coarse sand and cement mortar. This type of concrete is mostly used as a foundation or substrate. Such concrete can be made at the bottom of the formwork when arranging the foundation. In this case, when preparing, a small amount of water must be added to the mixture in order to acquire its density. Strength in this case will be absent, but this material will have protection for the foundation.

For the manufacture of more durable concrete, it is necessary to use all kinds of crushed stone as the main fillers, having a fraction from 2-3 mm to 35-40 mm. The quality of such material will depend on the components used, and composition.

Based on this, we can draw the following conclusion - before you start to understand the methods of preparing concrete and its proportions, in order to be able to make a concrete solution correctly, you must very carefully study each of its ingredients separately.

Requirements for the components of concrete

Cement.

Cement is one of the most important and one-of-a-kind components that binds all the ingredients together. Portland cement is considered more suitable for the manufacture of concrete. It is distinguished by a high content of calcium silicates (up to 79-80%). This, in turn, will provide better adhesion and excellent bonding of all materials. But still, depending on the task, any other types of cement can be used.

A cement grade more suitable for frequent use is 500. You can also use the standard grade M 400. But this may affect the life of the foundation. Portland cement is excellent for working at low temperatures. But still, it should be remembered that it is impossible to work with concrete at temperatures below 15 degrees. But if there is a good reason for using concrete at a very low temperature, then you will definitely need the use of special additives and various plasticizers. We will talk about this later.

When working in hot weather, it is better to use Portland slag cement. In the Russian marking of cement, in addition to the designation of its strength (MPa), there is also the designation D. After this letter, as a rule, a number is written that indicates the amount of impurities in this cement. Thus, for the manufacture of concrete of excellent quality, cement of the M500-DO or M500-D20 brand is best suited. (with impurities from 0 to 20 percent).

The cement must be dry. You can not buy very damp cement with lumps. Also, you do not need to save too much on its acquisition, and buy unmarked material, or stale. And all because concrete will be used for the construction of the main elements of a residential building. And the quality of construction will depend on its appearance. Remember that it is because of this fact that your safety depends. In poor conditions, cement begins to absorb a large amount of moisture from the air. Thus, its main qualities are lost.

It is better to buy the volume of cement you need in advance (2-3 weeks before its use). When buying, be sure to carefully check the presence of markings and the integrity of the package itself.

Sand.

Regardless of which aggregate you use (gravel or crushed stone), you will also need sand. Only in some cases, you can do without it, when it is possible to compact the large aggregate in such a way that all the gaps between the components are small. The sand that is more suitable for the manufacture of concrete must necessarily contain a fraction from 1.7 to 5 mm. But it is best when this material has a uniform size (no more than 1-2 mm). The sand should not contain various third-party impurities. Various plant residues or any inclusions that are likely to decay over time will adversely affect the strength properties of concrete. But if the sand is not very clean, it is easier to sift it through a special sieve with small cells. The same can be done with rubble. In the manufacture of concrete, it is best to use river sand. Of course, this material will differ in cost from the ravine, but it will have the required grain size, and it will not contain silt inclusions and clay. The most important thing is to ensure excellent adhesion of the cement mortar, which has large aggregates, which will determine the strength of the concrete itself. It follows that it is better not to use sand containing loam or grains smaller than 1 mm in the manufacture of concrete, since it will be very difficult to remove them. To do this, it is necessary to carry out the procedure for settling the sand and washing it, which is difficult to do even in industrial conditions. For those places near which stone quarries are located, artificial heavy sand can be used. It can be obtained by crushing rocks. It is distinguished by its density and greater mass. If, however, an excellent washing is carried out and the particles are sifted by size, then this material will be better than river sand in its properties. It should only take into account the fact that during its manufacture and further use, concrete will be much heavier. This is an important fact if it is used in the manufacture of screeds over multi-storey floors. A weighty obstacle to the use of heavy sand can be a high background of radiation.

Aggregate. Gravel, crushed stone.

The main and main strength of concrete is provided by crushed stone and gravel. River or sea pebbles will not work in this case, since the surface of this natural material is polished with water, thereby not being able to provide the desired adhesion to the solution. Best of all, as a filler, the material that is obtained from crushed rock is suitable. Very often, expanded clay is also used, or some similar material, which is quite durable, but at the same time light. Below, in our article, we will consider in more detail the principle by which it is possible to select the right material for the manufacture of concrete, which ensures its reliability and strength.

In order to make concrete with your own hands, it is important to consider its composition and proportions. Now we are talking about important materials that are used to make concrete composition. In this part of the article, we are talking about an important component of concrete - gravel and crushed stone.

The size of crushed stone or gravel can be from 9 to 35 mm. And large pieces are used to a greater extent in production, but very rarely. It is best that the aggregate contains a small amount of dust or various clay impurities on the surface. All debris should be removed before the gravel is introduced into the solution. The greater the roughness on the faces of the particles, the better. Excellent and reliable grip will depend on this fact. In order to make concrete with your own hands, it is best to use the aggregate in which there are particles of various sizes, or to mix coarse gravel with medium. Since you don't have professional equipment to compact the concrete, this will ensure that the aggregate particles used fit together better, and won't allow large voids to form. Otherwise, they will become filled with mortar, and this will directly affect the strength of the concrete itself.

It is best to store crushed stone and gravel in bulk. And this material should be stored near the place of its use. To avoid contamination of these materials, it is best to store mounds on a dry tarpaulin or an area with a solid foundation. In a simpler version, when all materials are scattered directly on the ground, it is not necessary to use the bottom layer that was in contact with it when making concrete.

Water.

A very important point in the manufacture of concrete is the choice of water. It must be clean, and not have foreign impurities and alkaline inclusions. Also, do not use river or lake water. You just need to follow the following rule: the water that is suitable for drinking will also be suitable for making concrete. If you follow this rule, then your concrete will be able to serve faithfully for many years.

Additives: Lime.

Most craftsmen who add some slaked lime to the concrete composition, thereby increasing the concrete's workability. This can make the process of leveling the concrete screed much easier. But still, lime can adversely affect the good bonding of cement with aggregate. This in turn will affect strength. By the way, no one extinguishes lime on their own for a long time. You can use already prepared lime (slaked). It can be found for sale at any hardware store.

plasticizers.

In order to give the concrete mortar good fluidity, or vice versa, to ensure maximum viscosity, as a rule, different plasticizers are used, which are ways to change the properties of the mortar in the right direction. The use of plasticizers can significantly increase or decrease the amount of water needed to make the mortar.

To fill the foundation, it is not at all necessary to use plasticizers, but nevertheless, they will play a big role if the foundation has a rather complex shape, or the reinforcement will be denser. And more fluid concrete can reliably fill all the voids, which in turn can speed up the process and improve the final result.

Plasticizers for concrete. Auxiliary elements.

In addition to all of the above, it is quite possible to use special additives to give concrete progressive properties. For example, additives can be used to harden and set concrete at low temperatures or in the presence of high humidity. Appropriate additives are also used for the desired purposes. Most importantly, determine for yourself the need for their use, as well as choose the right supplement in a specialized store. In this case, it is important to carefully study the instructions for the properties and use of these additives.

In the same case, if the conditions for the use of concrete will have boundary parameters, in terms of humidity and temperature, then the use of plasticizers and various additives will be necessary.

reinforcing substances.

In addition to aggregates for concrete, specific additives for reinforcement are often used. For example, when using concrete to make a thin screed, as a rule, PVC or polypropylene fiber is used. This material is very soft and rather fragile, but thanks to its use, situations can be avoided when the concrete begins to crack in those areas where the floor slabs converge.

Selection of the ratio of all materials for the manufacture of concrete

For certain purposes, as a rule, a different composition of concrete will be required. Suppose, for the manufacture of a foundation for a residential building, it is necessary to use more durable concrete, which will contain large crushed stone ranging in size from 25 to 35 mm, and a certain amount of mortar, which will be enough to strengthen the aggregate. In this case, it should be fluid, since it is necessary to more reliably compact the concrete and try to remove all the formed air bubbles from it. But still, before you start pouring the main amount of concrete, you must first equip the substrate. As a rule, simpler and not very durable concrete B 7.5 is used for this, which, in addition to cement mortar, includes coarse sand. Since the concrete solution is not made very liquid, and it looks more like wet soil.

For the manufacture of the foundation, an average fraction of aggregate is required, as well as a liquid mortar. This will help ensure that the solution spreads more easily over the surface in a thinner layer. In addition, the medium and small fraction of the aggregate will be necessary in the manufacture of decorative elements, balusters, or some kind of garden utensils.

The composition of concrete by components and their ratio must be carried out in accordance with GOST 7473-94 and SNiP 5.01.23-83. In this case, you must also consider the density of each component, and the average density of the concrete. After making the necessary calculations of all the ratios of the ingredients, you can begin to manufacture concrete and pour it.

More common proportions of concrete are 1:3:6 parts of cement, aggregate and sand, and 0.5-1 parts of water. But still, very often adhering to this arrangement, as a rule, concrete will not be of very good quality. And this can be seen only after a certain time. Best of all, make a simple calculation and prevent trouble. After carrying out the necessary calculations, you need to correctly choose the method of measuring the components. You will only have weight and volume parameters on hand, and, unfortunately, they are incompatible with them. Material such as sand can be very wet or loose. It follows that one bucket with a volume of 10 liters will not have the weight that can be calculated from the ratio of density to volume. If you disassemble the moisture content of the same sand and gravel, then they must be dried before calculating the required number of servings of these ingredients.

And in order to be able to determine the friability and calculation of portions, it is necessary to weigh the portions of each component to one volume. To do this, take a bucket or other container and fill it with sand, aggregate and cement without tamping, and weigh the resulting portion.

Then, after making simple calculations, you should translate the resulting calculations into the ratio of buckets.

How to mix concrete

Above, we have described in detail each component of concrete. Now it’s worth talking about how to make concrete for the foundation with your own hands. Right now it is worth specifying what proportions should be used in this case.

In order to replace concrete, it is necessary to use special concrete mixers. Only in this way it is possible to more efficiently and quickly mix all the ingredients and deliver the resulting concrete to the right place. You can also make your own concrete. There are two popular options:

In the first option, you must first mix all the ingredients in a dry form, and only after that, pour water.
In the second option, cement, aggregate and sand are poured into the measured and poured water.

When mixing the ingredients in a dry state, it seems that all the materials are distributed more evenly, but still, when adding water and mixing on your own, there is no one hundred percent guarantee that the entire volume can quickly get wet. As a result of this work, you will get the following: an unmixed dry composition will remain at the bottom. And this means violations of proportions.

If this composition is mixed for a long time and thoroughly, then a lot of time will pass, and the solution will again begin to harden and delaminate. And when all the necessary components are added to the water, the cement will knead for a rather long time and will not be able to adhere to the filler.

The second option is still slightly better than the first. Based on this, it is in this way that it is necessary to mix concrete in small quantities.

Now we have been able to find out that hand kneading is not very good. The easiest way is to rent a concrete mixer or buy one. The concrete mixer should be located no further than 40-45 meters from the place where the concrete will be applied. All components should also be located near the concrete mixer.

concrete mixing

The volume of a standard concrete mixer is 200 liters of prepared mortar. To this figure, it is necessary to carry out all calculations for the number of each component.
Then you need to do the preparation of concrete, adding it to the concrete mixer.
After that, a certain amount of water is introduced into it. Approximately 10-15% can be added later. This in turn can facilitate mixing after all materials have been added.
Next, cement should be laid. If you were left with some water, then the cement can also be left in the same amount.
Now the sand is falling. Mixing at this stage is necessary until a uniform distribution of all components is obtained.
After the cement mortar is made, the necessary add-ons should be added to it. components (additives, plasticizers). The last to fill up is the main aggregate (crushed stone, gravel).
If you need to add water, then you should first mix it with cement, and pour the resulting cement milk into a concrete mixer. This procedure should take you about 10-15 minutes. If you interfere longer, then the cement in the solution will set.
Delivery of the solution is carried out using a wheelbarrow. If the entire mixed solution does not fit in a wheelbarrow, then its remains must be left in a working concrete mixer.

Pouring concrete

Now you need to competently pour, and then distribute the concrete. The result will depend on this work, but to a lesser extent than on the two previous options. Concrete is a heterogeneous solution. This means that in order to properly distribute it, it is necessary to compact it, so that the aggregate can be more tightly packed inside the solution itself. Also, you need to carefully monitor that there are no air bubbles in the solution. For this, as a rule, vibration is used. The use of special vibrators will help to compact concrete more efficiently. For the installation of walls and foundations, a special unit is used, which is equipped with a vibrating hose. The latter is immersed in the solution, and then compacted.

For the manufacture of a thinner layer, such as a screed, surface tools with a long rail are used. Under the influence of fine vibration, the solution is mixed over the surface. The surface of the concrete, in this case, will be leveled and immediately compacted. When pouring concrete, use a sharp rebar and pierce it to the full depth of the solution. In this way, all the accumulated air in the solution will be released. Since the pouring occurs gradually, when piercing a new portion of concrete, it is necessary to deepen the rod by 10 cm into the previous layer for better bonding. The last step is to level the top layer. This process can be carried out in several stages, depending on the adhesion of the solution and its complete drying.

Stages of building a barn with a pitched roof with your own hands Garden without the hassle: no digging, no weeding and no watering

There are many methods for preparing concrete and its processing, adhering to which it is possible to produce material according to characteristics no worse than granite or marble. Nowadays, more and more people are abandoning the latest materials in favor of concrete, but not purchased, but made by themselves.

The content of the article on the manufacture of concrete with your own hands

Making concrete with your own hands: the main components

It is not so difficult to prepare concrete on your own. For this you will need the following components:

sand;
cement;
crushed stone;
water;
additives-plasticizers, dyes and other additives.

Sand for making concrete

Sand should not contain a large percentage of clay and other impurities. According to GOST, it must correspond to class 1 sand: the percentage of impurities of clay and dust particles is not more than 1%, and the filtration coefficient is 5-7 m / day. These characteristics correspond to river and sea sand. It is better not to use quarry sand, because it is fine and contaminated, it will not make high-quality concrete.

To check if sand is suitable for future concrete mix, conduct a simple experiment. Stir some material in a jar of water. Considering that it sinks to the bottom, and the additives rise up, the water should be clean. If so, sand will do.

What should be the rubble?

Crushed stone is a crushed hard rock. Crushed stone binds concrete mortar well, as it has rough edges with jagged edges. The use of pebbles, even crushed, is not allowed. The crushed stone size is 5-20 mm.

Do-it-yourself cement brand for making concrete

The strength characteristics of concrete depend on the brand of cement. The brand 500 is often used, 400 is also allowed, but no less. This indicator is the strength after 28 days of hardening (MPa). You also need to use fresh cement, since during long-term storage it loses its strength characteristics: every month - minus 10 percent. This is especially important when building a foundation, because this is the main part of the building.

What should be the water?

For the manufacture of concrete, pure water without bleach, oils and other additives is used. For normal binding of cement, about 20% of water from the total mass of the material is sufficient. With an excess of liquid, the strength of concrete decreases, as water evaporates, and cavities are left inside.

It is important to choose the right dry building mixes, because the quality of the prepared concrete mainly depends on them. We talked about the choice of dry building mixes in another article.

DIY concrete: proportions

To make concrete with your own hands, and the mortar was of high quality, be sure to use high-quality materials and stick to proportions. For the production of concrete similar to B20, the following are recommended: proportions by weight:

cement M500 - 1 part;
sand - 2.6 parts;
crushed stone - 4.5 parts.

We recalculate these indicators for the preparation of 1 meter of cubic concrete B20:

cement M500 - 315 kg;
sand - 850 kg;
crushed stone - 1050 kg;
water - 125 liters per 1 m3 of the finished solution.

Important! To make concrete with your own hands, the proportions must be observed one to one.

Mixing concrete manually and mechanically

At first glance, it may seem that making concrete with your own hands is very simple, and there is no difference how to mix the components used together. We keep the proportions, and it's in the bag. No it's not. Cement does not dissolve very well in water, it forms lumps. To avoid this, it is important to adhere to concrete manufacturing technology.

1. Pour the required amount of cement into a dry prepared container.

2. Add sand there and mix the dry mixture thoroughly.

3. Add water and mix everything.

4. Lastly, add crushed stone.

The use of a manual or mechanized method of mixing concrete depends on the amount of mixture to be prepared. Naturally, it is much easier to use a concrete mixer (concrete mixer). An inexpensive concrete mixer for home use (not suitable for industry) will cost you 10,000 rubles. This will not interfere with large-scale work, for example, when do-it-yourself floor screed.

If you do not want to spend such money, and work with concrete is not very frequent, use an old bathtub, a trough or just a sheet of tin. The component for the preparation of concrete with their own hands is mixed with an ordinary shovel. It is economical, but non-technological, antediluvian, inconvenient and long.

We make a dye for concrete with our own hands

So, in the previous part of the article, you learned how to make concrete with your own hands. But, as you may have guessed, you are unlikely to decorate something with such a mixture, because it does not look very aesthetically pleasing. To get rid of this problem, consider how to make decorative concrete with your own hands. The main highlight of decorative concrete is the use of coloring pigments.

Acid dyes are often used to color concrete. To prevent the liquid from flowing down the walls, gel-like dyes are used for the concrete mixture.

To prepare a dye for concrete with your own hands, you will need the following materials:

solvent;
adhesive;
coloring pigment of any color;
fixing additives.

Mix all the ingredients together until a gel-like mixture is formed. At the end, a coloring pigment for concrete is added so that the mixture acquires a certain color. That's it. You can start painting the concrete base.

Considering that the color range of dyes available on the construction market is not too extensive, in order to obtain the desired result, you need to buy and mix several different colors. Before applying the dye for do-it-yourself concrete, the surface is treated with a solvent.

Important! When working with acid dyes (homemade or purchased), take precautions to protect yourself, all surfaces and tools as you work with acid.

Preparing concrete at home means more work to come:

building your own house;
building a garage
organization of a basement for a vegetable store;
installation of outbuildings;
pouring the site in front of the house and many other works where concrete is required.

The organization of production in domestic conditions is caused by a number of factors:

a small amount of work;
the desire to save money in the preparation of building material;
lack of concrete plants within transport accessibility from the place of construction work.

Concrete is an artificially created stone building material used for the construction of various structures. Consists of binders, mineral fillers and water. Often, in domestic conditions, various cement-based solutions are classified as concrete, for example, floor screeds made from a mixture of cement, grus and water.

The main difference between concrete mixtures and others is the presence of large fractions of mineral fillers in the composition of the solution.

In industry, concrete is designated:

compressive strength classes, denoted by the letter B and numbers, - shows the temporary resistance of the material when exposed to axial load;
concrete grade for compressive strength, denoted by the letter M and numbers, - means the maximum load that the material can withstand before destruction.

Indicators "B" and "M" depend on the composition of the concrete, the conditions of its preparation, laying and the exposure time until the acquisition of maximum strength. According to the technical documentation, 98% of the strength is acquired at the end of the exposure for 28 days.

Examples of classes and grades of concrete

Class B20 means that a cube with dimensions of 150 x 150 x 150 mm is able to withstand a load of 25 MPa without destruction.

For example, - the most used concrete for an irresponsible structure has the grade M50 ... M200, or according to the strength class B3.5 ... B15.

All these data are given for reference information, which can serve as a guideline for home concrete preparation. It is much more important to know the approximate proportions of the components used in the composition of concrete.

Concrete mixtures, according to the amount of cement used, are:

poor, skinny, - mass fraction of cement is 5 ... 15% of the total composition; for an ordinary consumer means a ratio of 1: 8 ... 1: 5, respectively;
standard, commodity, - the composition of the mixture corresponds to the state technical documentation; in everyday life, this ratio is determined by the proportions 1: 3 ... 1: 4;
fatty, - the ratio is 1: 2 or more.

From this information, it can be seen that an increase in the amount of cement in the composition of concrete leads to an increase in the strength of the latter, but also leads to a significant rise in the price of the final product.

From the used fillers, the gradation of concrete ranges from extra light to extra heavy.

The choice of concrete composition

The composition of concrete and its strength are directly related, therefore, the primary task is to determine the object of work. For example, the composition of concrete mixtures for a foundation under a house or a sidewalk will be different due to the difference in the perceived load.

The main components of concrete

cement;
quartz sand;
mineral stone filler;
water;
plasticizers.

Cement

For home conditions, cement of the most common brand M400 or, as indicated on the packages, "Portland cement 400 D-20 GOST 10178-85" will suffice. A smaller brand is weak concrete, a larger one is stronger, but also more expensive.

Purchase cement in factory packaging, which contains the maximum possible information about the contents, the production address is indicated.

Deviations in designations and a suspiciously low price will mean:

counterfeit products manufactured with all sorts of deviations from GOST;
the package contains cement diluted with powdered waste from metallurgical production - they have approximately the same color and weight;
stolen products.

It is better to purchase cement with a release date that does not exceed a three-month milestone - after 1 month of storage, the product loses up to 10% of its properties; a shelf life of more than 6 months indicates that over 50% of the technical properties have been lost.

Pay attention to the storage conditions of cement - especially in various construction markets where outdoor storage is allowed.

Quartz sand

Ideally, it is better to use washed sand without impurities with a coarse fraction not exceeding 5 mm. If it is impossible to use such sand or in order to save money, it is possible to use ordinary river or "ravine" material.

Fine-grained sand binds cement and fills the space between large fractions of mineral filler. Before use, it is recommended to sift such sand through a sieve to remove large inclusions of clay or debris.

In the case of using concrete, which includes clayey sand, it is not recommended to use it for the construction of load-bearing beams above openings or interfloor ceilings due to rather low strength properties.

Note. Over the past decades, gruss, a sedimentary rock with a fraction of 2–15 mm, has been introduced into the composition of “home-made” concrete. Such concretes can be used for foundations for fence posts or local power lines, as well as, with the use of reinforcement, for floors in your own house or outbuilding.

Mineral stone filler

As a filler of large fractions, a gravel-crushed stone component is used - mountain sedimentary rocks or mechanically crushed stone. In domestic production of concrete, it is advisable to use fraction sizes of 5 ... 30 mm - the use of larger sizes will complicate direct mixing of the mixture.

River pebbles are not suitable for concrete preparation due to the fact that the stones have a rounded smooth shape, while gravel and crushed stone have a structural rough surface, which increases adhesion with cement.

If possible, then in the manufacture of concrete it is allowed to use a substitute for the gravel-crushed stone component - gruss, while the mass fraction of the replacement can be up to 50% of the large stone filler. This can be explained by the fact that the composition of gruss includes a fine fraction, from dusty to particles with a size of 4 ... 5 mm.

Water

When mixing a dry mixture, it is allowed to use clean, pollution-free, water with neutral acidity and alkaline reaction, that is, close in these parameters to drinking water.

For example, "soft" water has an increased alkaline component - when washing the hair of the head, there is a feeling that it is not possible to wash off the soap solution.

“Hard” water has an acidic composition, it removes the soap solution well, but after drying, whitish stains remain on the glass.

During construction in places with difficult water supply, it is allowed to use rainwater or water from natural reservoirs, which must be defended in a container.

It is necessary to pour from such containers carefully so that settled dirt does not rise from the bottom. But, in such cases, the concrete mixture must be made fatter, in order to compensate for deviations in the chemical composition of the water.

plasticizers

Chemicals that give the concrete mixture certain properties:

increase or decrease in the viscosity properties of the solution;
lowering the setting temperature, which is important when working in frosty time;
improvement of hygroscopic characteristics and many other properties.

When using concrete for ordinary structures in normal climatic conditions, it is not advisable to get carried away with plasticizers - this will increase financial costs and may lead to the opposite result, that is, a deterioration in the properties of concrete.

Note. To increase the strength of concrete and its resistance to cracking, it is recommended to use metal building fiber - small pieces of wire with a diameter of not more than 1 ... 1.5 mm and a length of up to 50 ... 70 mm. This is important for planar structures, such as floor slabs or stairs.

The preparation of a concrete mix and theoretical, in this case, recommendations of proportions used in industrial production are not very compatible things.

This is due to the fact that in the factory the requirements for the initial components are met:

mass or volume fractions are determined by means of mechanical devices with high accuracy;
the technical conditions for the preparation of the concrete mixture are maintained, - the speed of rotation of the drum, the duration of mixing, temperature conditions.

The unit of measure in the field is often the bucket of a shovel or a construction bucket. The composition of concrete, approximately corresponding to the grades of concrete M200 ... M250, is the ratio of cement-sand-crushed stone in a ratio of 1: 3: 4, which means that three buckets (ladles) of sand and four buckets of crushed stone are taken per bucket (shovel bucket) of cement . For this volume, 1 ... 1.5 buckets of water are used.

Preparation of concrete mix

Preparation of the mixture is one of the important steps. In the case of a frivolous approach, there is a risk of getting an unmixed concrete mixture with poor strength properties.

In domestic conditions, it is possible to use two main types of mixing:

mechanical, using a concrete mixer or, for small volumes, a powerful drill with a special nozzle;
manual way,- with the use of a bayonet shovel and human muscle strength.

mechanical method

The use of a power tool will require the presence of an electrical network or a gas generator as a source of electricity.

The sequence of loading into the concrete mixer:

into the switched off concrete mixer water is poured, up to 75 ... 80% of the required volume, after which the mechanism starts;
evenly fed the required amount of cement, - cement milk is formed;
sand is added
if necessary, they are sent to the concrete mixer plasticizers, steel fibers and other additives;
the last is gravel-crushed stone filler, after 2 ... 3 minutes it becomes clear whether it is necessary to add water or not;
final mixing carried out for at least 10 minutes.

The loading process with the concrete mixer running is dangerous - therefore constant attention and accuracy is required!

The finished mixture can be fed directly into the formwork or poured into an intermediate container with subsequent distribution throughout the object.

Manual way

A very laborious process. With this method, a prepared site will be required, on which a technological container for mixing the mixture is located, for example, half a cut 200-liter barrel. In the absence of such, it is possible to enclose the formwork to prevent the spreading of the liquid concrete mixture.

Unlike the mechanical method, dry components are loaded immediately in the required proportions, after which they are mixed until they acquire a uniform, uniform shade, approximately light gray, like that of dry cement.

Next, water is added - the first part should correspond to half of the required amount. In the process of mixing, water is gradually added until the solution acquires the desired consistency.

When mixing in enclosed or limited containers, pay special attention to the corners and middle - there may be the formation of "stagnant" zones where the mixture will be poorly mixed.

It is possible to mix the ingredients on an open horizontal platform, but then, when adding water, you will have to work at a high pace, so that the water that has not entered the solution does not have time to spread.

It is advisable to use the manual method with a structure volume not exceeding 2 ... 4 cubic meters - this is explained by the fact that there is simply not enough time and physical strength, and it is better to pour concrete without long breaks.

With proper selection of components and careful preparation and laying of the concrete mixture, it is quite possible to obtain structures that are comparable in strength to the factory ones, but will be much cheaper.