How to properly mix concrete mortar for the foundation. How to properly prepare cement mortar for the foundation. Exact proportions of the solution

It is difficult for someone who has never dealt with cement to understand what it is. concrete mortar and how to prepare it correctly. But even experienced builders do not always understand all the intricacies of working with it. In this article we will describe not only the process of preparing concrete mortar, but also the correct selection of its components.

Cook it yourself concrete mixture for pouring foundations, small reinforced concrete structures, the paths are easy. You can knead it in any old bath, trough, box or knocked down wooden shield. When producing a small amount of solution, the process can be mechanized using special attachments. If you need a lot of concrete, you will have to use an ordinary shovel, small garden fork, hoe or other suitable device for the occasion. But before you start kneading, you should choose quality cement, crushed stone and sand.

Concrete components

Quality of the main component - cement

The strength of our mortar will be determined primarily by the quality of the cement, so it right choice especially important. There are many factories in Russia that produce similar products, and they usually sell them in neighboring regions. Therefore, you should focus not so much on the manufacturer, but on appearance cement.

You should definitely pay attention to the date of manufacture - over time, its activity decreases sharply. Fresh cement, when squeezed in a fist, does not turn into a lump, but easily spills between the fingers. High-quality, finely ground products lose their properties especially quickly during storage.

When counterfeiting it, dolomite dust, mineral powder, ash and other fillers are used. When they are mixed, naturally, the concrete will not only set more slowly, but after hardening it will also not be strong enough:

• the color of high-quality cement powder is darker;
• the solution from it sticks well and sets quickly;
• the color of the dried concrete outside is a little lighter, but if you knock off a corner, it inner surface dark;
• After complete drying (after a month), it is very difficult to hammer a nail into the finished concrete.

NOTE: You can check the quality of purchased cement as follows. Mix a small amount of concrete into the right proportions, and after hardening, install a chisel on it and hit it with a hammer. On high-quality concrete, after an impact, only a light mark will remain. If the metal breaks off small pieces, the cement grade is 200. Did the chisel punch a half-centimeter hole in the concrete? Cement grade not higher than 100.

The strength of the mortar depends on the brand of cement. When designating it, the numbers after the letter M mean the ability to withstand a load of 1 cubic meter. cm. That is, M200 cement can withstand a load of 500 kg per cubic centimeter. Naturally, the higher the grade, the stronger the concrete will be. Special grades with a strength of 600-700 are rarely used, so when working with complex or multi-tiered structures It is better to use cement grade M500.

The letters following the numbers indicate the presence of additives in it. For example, the product of the M500 B brand is quick-hardening, VRTs is waterproof, BC is white, intended for finishing. The designation BC20 will mean that it contains 20% brightening impurities. The most important additive for us - PL - makes it frost-resistant, so it is advisable to use it for street work, especially in the conditions of Siberia and the North.

At long-term storage The cement powder cakes, becomes compacted and its specific gravity increases. Therefore, if you bought it in advance, be sure to store it in a dry, draft-free place. It is advisable to additionally wrap paper bags with plastic wrap. Please note that after six months of storage, its quality will decrease by at least a third.

Which sand is better

Most best sand- river. It is washed with water and, unlike quarry, does not contain impurities. When working in winter period It is better to use river water, completely free of clay inclusions. At sub-zero temperatures, their lumps do not dissolve well in water even with prolonged stirring, and the surface of the concrete will be uneven.

Selection of crushed stone

Dolomite and limestone crushed stone are most often used to create small, lightweight structures, the quality of which is not subject to increased requirements. Gravel or granite material is more durable and can withstand the coldest temperatures.

IMPORTANT: When purchasing, you should remember the most important rule. Dirty crushed stone or sand are the main enemies of good, high-quality concrete.

Let's prepare the solution

The proportions of the mixture directly depend on what brand of concrete (that is, what strength) we need. The most common proportion when using the M500 brand is 1:2:3 (i.e. you will need part cement, two sand and three crushed stones). The higher the grade, the less cement is used. Therefore, the proportions for the M350 will be different. In any case, the ratio of water and cement should be no more than 0.5.

Table - Concrete made from M500 cement

For the manufacture of garden path M200 concrete and small fillers (pebbles or crushed stone) are sufficient. Good and durable asphalt will be obtained from grades 300 and higher. The foundation naturally requires a more durable structure. Ideal option will become M500. On average, one cubic meter of mixture will require 6-7 bags of M500 cement.

IMPORTANT ! Remember that the prepared mixture hardens very quickly, so it must be used within half an hour. Under no circumstances should you try to dilute it with water once it has hardened.

To avoid the formation of unmixed lumps, water is added only after mixing the cement with sand. Blend for plastering works must be sifted through a sieve with mesh size 5 mm, for ordinary work larger cells can be used.

Concrete path on personal plot or near a private house - a practical and convenient solution. And if you make it with creativity and taste, it will also become wonderful. decorative element. Moreover, in order to cope with similar work, it is not at all necessary to be an experienced builder.

To each home handyman It’s quite possible to make a path, . And today we will tell you about the various intricacies of making paths, we will talk about what kind of solution to put the plaster on, how to fill the product with a mixture with a mesh, what proportions are used for concreting paths and much more.

Product Features

In order for the finished concrete path to serve for a long time and not be pressed underfoot, you should take care proper preparation grounds.

1. Having previously drawn it on paper, mark the outline of the future path on the site using pegs and a stretched rope.
2. They remove a layer of earth (twenty centimeters) and cover it with a layer of ten to fifteen centimeters.
3. Then they lay a special polymer material– geotextiles. It will give strength and prevent weeds from growing.
4. The last layer is placed, which must be moistened (so that moisture from the concrete does not go into the ground) and compacted. The sand layer is four to five centimeters.
5. Then formwork made of boards is placed along the edges of the path.

The solution, as a rule, is poured into molds, which can be of different designs: rectangular, polygonal, round, imitating natural stone. Polypropylene molds are often found on sale, with which you can quickly make entire pieces of a path with a beautiful pattern.

The outer walls of this stencil, which can withstand at least a thousand pours, have a thickness of 6 millimeters, and the inner walls are 3 millimeters. Height – from 5 to 6 centimeters. It is equal to the thickness of the tile.

The resulting seams between individual tiles can be sealed with cement mortar contrasting color, cover with sand or sow decorative lawn grass in these places.

How to make it strong cement mortar(cement mortar) for a garden path and how to prepare concrete mortar for pouring, read below.

Composition and structure

Ingredients

So, let's try to prepare a high-quality solution for the garden path at the dacha with our own hands. For the solution, classic materials are used - sand, crushed stone and water. They must be of appropriate quality:

• Sand– washed, dry, not too small (so as not to absorb too much water) and not too large (so as not to reduce the plasticity of the concrete solution).
• Crushed stone– also take pure, with a fraction from five to ten.
• Cement– preferably high grade (M400, M500). It must be crumbly and dry. By the way, the brand of cement can be visually determined by the color of the powder. The darker it is, the higher the brand.
• TO water there are no special requirements. Do not use only sea or very dirty water.
• Sometimes, to increase plasticity, a certain amount is added to the solution. clay.

Recipe

Now let's talk about the recipe. It may be different. You can, for example, make a solution only from sand and cement (without using crushed stone). Or vary the ratio of ingredients. By the way, buy ready solution undesirable. It may be of poor quality.

And here are the recipes:

1. One part cement plus three parts sand plus water (you can add a little clay).
2. One part cement plus three parts sand plus three parts crushed stone plus water.
3. One part cement plus two parts sand plus two parts crushed stone plus water.

To give the desired shade, coloring pigments-additives can be added to the solution for garden paths. For example, the HLV brand. This pigment, produced in four main natural colors (red, green, yellow, brown), will require about 250 grams per 25 kilograms of dry cement.

The following video will talk about popular mistakes when making garden paths:

Manufacturing

After measuring out the dry ingredients, mix them. You can do this in some clean container using a shovel or hoe. If you have a concrete mixer, then it is better, of course, to use its help. Water must be added little by little so that the finished mixture does not flow, but drips slowly (like thick sour cream from a spoon).

Having prepared the base as described above (removing the turf from above, pouring crushed stone, sand, laying geotextiles and making formwork), you can begin to create a path. The easiest way to do this is using a ready-made plastic mold. It is placed on damp compacted sand and the solution is poured into it. After twenty minutes, the mold can be carefully removed and the process repeated.

While the mixture has not hardened, you can decorate the path. By pressing, for example, pieces into its surface tiles or cute pebbles, laying them out in a beautiful pattern. To strengthen it, within two hours after pouring the solution, you can cover it with cement laitance using a brush.

Do it yourself

Coloring composition

It looks elegant and beautiful on the path.

• For this purpose, you can buy ready-made pigment and introduce it at the time of preparing the solution.
• You can also add a little acrylic paint.
• Another option: rub the wet concrete surface with a mixture of cement (two parts) and dye (one part). This is called ironing:
  • To make a path yellow, for example, ocher is added to cement.
  • The red color comes from one portion of white cement, two portions of sand and half a portion of umber.
  • A green tint is achieved by adding to sand and white cement glauconitic green.
  • Black - taking one part gray cement, one and a half parts of sand and 0.15 parts of ordinary soot.

If, when pouring a garden path, you need to trim it, the following video will help you with this:

Supplements

We have already told you how to make a standard solution.

• Now we should mention the additives that are introduced, in particular, to increase strength (for example, propylene-based fiber).
• Special components designed specifically for concrete garden paths (HLV-15) are also sold.
• If there is a desire to imitate, then stone chips and the appropriate dye are added to the solution for plausibility.

In addition, the surface of the finished path can also be treated with a hardening compound.

• Impregnation made on the basis of wax and synthetic resins gives a good result. It is applied with a brush or spray.
• The coating, in addition to significantly increasing strength, gives a very beautiful smooth surface.

Forms for paths

Ready plastic molds convenient, but they require certain costs. If you want to save money on this, then it is quite possible to make these elements yourself. For example, like this:

• Let's place thin boards on edge directly in the formwork, using them to create partitions in in the right places and getting your favorite pattern. We use a “half-tree” connection.
• Let's put together a rectangular frame from wooden blocks. The bottom (which does not need to be secured) is a sheet of metal or plywood. placed on the table, with a frame placed on top. At the bottom (if there is such an idea) a mosaic of pebbles or tiles is laid. Then the solution is poured in two portions, between which a metal reinforcing mesh is placed.
• To obtain round tiles, take a plastic basin. To make it easier to remove the form, we will lay plastic film to the bottom.
• To make a template for imitation natural stone, you will need the stone itself (cobblestone, granite,) and sculptural plasticine. The plasticine mass is softened (dropped in a bag in hot water) and press the stone into it. Then they tinker around wooden formwork. Pour in the solution.
• You can make templates from hoops from old barrels. They are bent as needed. And some other craftsmen cans They are used by removing the bottom and connecting them like a honeycomb.

The following video talks about the advantages of a polypropylene mold for a garden path, and how to work with it:

The need to maintain proportions

It is in the process of preparing the solution that a huge number of mistakes are made. Moreover, most often they are associated not with incorrect preparation of the solution, but with failure to comply with the required proportions of sand and cement, which is what leads to a result that the master did not expect to see. It is worth remembering that the quality of the final coating depends on the ratio of ingredients.

Composition of the screed solution

If you decide to prepare a solution for floor screed, its proportions must be studied in advance. The mixture consists of sand, fiber, plasticizer, and cement. The first ingredient must be sifted before use, which allows you to remove debris, foreign elements, and small stones. Among other things, only dry aggregate should be used. The M400 is most often used for work. The plasticizer is used, as a rule, by professionals. However, home craftsmen should also pay attention to this component, which can improve quality characteristics monolith. When you are preparing to screed the floor, the proportions of the composition must be observed, as this is an important component. Quite often fiber is also added. It represents If you plan to carry out repairs some time later, it is recommended not to purchase cement in advance. This is due to the fact that during storage it loses its qualities. That is why experts advise using only cement that has been stored correctly and was recently manufactured.

Solution proportions

If you want to make a mortar for floor screed, the proportions must be studied in advance. It is on them, as well as on the brand of cement, that the final result will depend. Thus, to obtain it, you need to add one part of M600 cement, as well as 3 parts of sand.

For M200 mortar, you need to use one part M600 cement and 4 parts sand. M300 will be obtained by adding one part of M500 cement and 2 parts of sand. It is worth noting that to obtain all subsequent grades of concrete, 1 part of cement of different grades is used. For M150 you should also use 3 parts sand. Before making a solution for floor screed, the proportions must be considered by the master. It should be remembered that the floor cannot be filled with a solution that has a grade lower than M50. The M200 is most often used for such work.

Mixing Features

If you decide to prepare a solution for floor screed, you can find out the proportions by reading this article. However, it is also important to know how the ingredients are mixed. Please note that dry and liquid ingredients should be mixed in different containers. Initially, it is necessary to combine all dry components, including fiber, cement and sand. Use cement mortar M 400, mixing it with sand, using a ratio of 1 to 3. Thus, 16.7 kg of cement will be needed for 50 kilograms of sand. Dry elements must be mixed for 5 minutes. Next, you should move to another container in which plasticizer and water are added. Approximately 190 grams of plasticizer should be added to a 50 kg bag of cement. Water should be added in an amount of 1/3 of the mass of cement.

For a third of a bag of cement you will need to add 5.6 liters of water. When mixing the floor screed solution (the proportion of each brand is indicated above), it is necessary to take into account that the plasticizer will require 0.6 liters. If you decide to prepare a floor screed solution yourself, the proportions for it are presented in this article. After completing all the steps described above, you can begin to mix the liquid ingredients; to do this, you need to gradually add the dry mixture to the container with the liquid, stirring it well. If you pour liquid into a dry mixture, lumps will form, and it will be very difficult to get rid of them afterwards.

If you decide to prepare your own floor screed solution, the proportion presented in the article will help you carry out the process without errors. It should be remembered that it is very difficult to carry out sealing work manually; among other things, such manipulations take a lot of time. Therefore, it is recommended to use a drill equipped with a special attachment. You must remember that using a power tool will allow you to carry out this work in a much shorter time, as well as with better quality. At this point we can assume that the preparation of the mixture is complete. It should be remembered that working with a viscous solution is much more difficult, but there will be much fewer cracks on the base after hardening. You can eliminate or minimize the number of cracks on the surface after hardening using a method that involves spraying the floor with water during the drying stage.

Determining the amount of mortar to form a screed

If you prepare your own solution for rough floor screed, you need to study the proportions in advance. However, it is also important to calculate the amount of mortar to form the floor. First you need to determine the volume building material, to do this, the coverage area should be multiplied by the thickness of the proposed screed. For example, if the floor surface area is 40 square meters, while the layer thickness is equivalent to 5 centimeters, then 40 must be multiplied by 0.05. This will allow you to get the number 2. This is exactly how many cubic meters of solution will be needed to form the floor in the described room.

But it is necessary to study, before preparing a solution for floor screed, the proportions of the composition. The next step is to calculate how much cement and sand will be needed. Due to the fact that the solution is made at a ratio of 1 to 3, 1.5 cubic meters of sand and 0.5 cubic meters of cement will be needed. Cubic meter cement has a mass of 1300 kilograms. This indicates that the work will require 650 kilograms of cement; this figure is calculated by multiplying 0.5 by 1.3. The above method allows you to calculate the consumption of the solution that is used to form a floor screed of a certain area. The master will be able to prepare all the required amount of building material in advance.

Features of pouring screed

If you are thinking about how to make a mortar for floor screed, you should study the proportions well. Among other things, it is important to familiarize yourself with the technology of work. Initially, the surface is treated with a primer, then beacons are installed, and at the next stage, mixing and filling are carried out. Priming is necessary in order to provide the base with excellent adhesion characteristics. This approach allows you to normalize the structure of the rough slab. If the surface has a porous base, then it is best to use a primer, while for a denser base it is necessary to use an undiluted composition.

Conclusion

If you are thinking about how to prepare a solution for floor screed, the proportions were indicated above. They will allow you to carry out the work correctly. It is important not only to maintain the ratio, but also to install beacons. They will ensure the evenness of the screed. The solution is prepared immediately before pouring.

To install them you need to prepare gypsum mixture, which is laid on the rough base in small tubercles. The solution for screeding a heated floor, the proportions of which were indicated above, should be prepared immediately before pouring. This will allow you to complete the work without haste.

During the construction process, rarely does anyone do without the use of cement mortar. Such material for construction work may be present in various finishing complexes. Cement is a substance that is not extracted from natural resources - it is created by exposure to high temperature on components, grinding them and adding impurities. The work of making cement itself is not high-tech. If you have certain skills, you can even make the mortar yourself, but first you need to find out how to make a cement mortar and what its proper preparation will involve.

What you need to know: composition and properties

Cement compositions for use in the construction process can not only be purchased, but also made yourself. To do this, you will need to mix ingredients, such as sand and cement, in the ratios required for your work.

It should be remembered that creating a cement-based mortar is a tedious task., and sometimes it is even impossible to complete it due to inexperience in evenly distributing the components.

A practical solution You can use a concrete mixer, but it is not necessary to purchase one - you can simply rent the unit or borrow it from friends.

The most popular cement is that which can be used in working with brickwork. Most often, cement and cement-lime type mortars are used for this purpose. The first option is used for the purpose of constructing load-bearing walls. As for the second, it is used to carry out work on laying walls inside, and only a small proportion of cement is added to its composition.

If the solution is to be used in winter, a special antifreeze additive will need to be added to its composition, which will prevent the consistency from freezing. However, despite this component, experts say that it is not recommended to make cement paste at a temperature of -20 degrees, since the components lose their qualities. If there is still a need for preparation, then it is important to obtain a solution that will have mobility and elasticity.

Experienced builders To increase the plasticity index, it is recommended to add shampoo: half a liter of this ingredient will be required per cubic meter of mass. Many people prefer to use salt as an anti-frost additive, but this should not be done, as there is a risk of efflorescence.

If the cement consistency is used as a base for creating monolithic hearths with an open source of fire, for a firebox or for constructing a stove, you need to use fire-resistant and heat-resistant solutions, which include a specific composition and clear proportions. So, to finish an open fire, you will need a grade of cement with an index of at least 400. Crushed stone is even added to the mixture, which includes red brick, in a ratio of 1 to 2. Next, two parts of finely ground fireclay sand are added to the composition. If the work concerns the firebox, then the composition will be identical, and the proportions will be as follows: 1: 2: 2: 0.33.

Tools and materials

Before you start mixing cement mortar, you need to familiarize yourself with some parameters that are fundamental in the process of creating a mixture at home. You need to dilute the consistency using components that are easy to obtain, so that later you don’t have to look around the city for the material that was once purchased only because it was exclusive. Due to the absence of one or another component, you can completely abandon the solution.

After all the materials have been prepared, you need to familiarize yourself with the technology for creating cement mortar. It is better not to give preference to complex recipes that a person who does not have a sufficient level of skill in construction cannot repeat.

The first thing to remember when manufacturing is that, even if they are used budget materials and primitive technology of creation, the cement should be reliable and strong.

For preparation you will need:

• plastic or metal containers (buckets, troughs);
• construction type mixer;
• fine sieve;
• water;
• wet sand;
• dry cement.

It should be noted that the list includes a sieve. It will be needed to carry out preliminary sifting of the ingredients, as a result of which you can obtain best quality kneading

How to knead correctly: preparing the components

Before you start cooking with your own hands cement composition, all components need to be prepared. Preparation is important stage, which will be decisive in obtaining a high-quality composition, so you need to know what may be required from a specialist at this stage. Before mixing the ingredients, you need to prepare the container. Its volume must be suitable in terms of consumption indicators for work.

If the prepared container is less than the volume of the resulting consistency, then the material that was obtained during mixing will be poured onto the floor or ground. If the selected container, on the contrary, is larger than the required volume, there is a high probability that the master will not be able to obtain a uniform mass: it will form lumps, resulting in a sloppy appearance, and the resulting construction will be technically dangerous. In addition, the selected container must stand stably on its platform and have increased strength.

Before you start the work process, you must sift the powder from which the mixture will be prepared. In addition, you should also know that it is not recommended to prepare the solution in the fresh air: standard cement can absorb moisture from environment, as a result of which it will lose its basic qualities. If possible, it is better to knead indoors.

Preparation of the solution

So, after all the materials and tools are prepared, You can start making the solution yourself.

1. 1 layer of cement is poured into the container, then a layer of sand, after which all layers alternate. The number of such layers should be at least 6. This way, all components can be diluted more efficiently. Sand and cement should be poured in the form of a bed. The total height should be no more than 300 mm.
2. The components poured into the container must be mixed several times with shovels until a homogeneous mass is obtained. Do not forget that the quality will depend on the mixing process ready mixture and further work. After everything is mixed correctly, experts recommend sifting the composition again through a sieve with 3x3 mm cells. The homogeneous mass must be absolute.
3. After mixing the dry ingredients, immediately add water or other ingredients, for example, liquid glass, it is forbidden. Adding liquid should be done gradually and carefully. Water must be added very slowly, this way you can control the process of acquiring the desired consistency. If the liquid supply is large, gradual addition will prevent the mass from becoming too liquid.

An equally important indicator for cooking is the temperature of the liquid: it should be neither low nor high. Try to use water whose temperature is close to the environment. Ambient temperature also plays an important role: ready-made cement mixtures must be diluted at an air temperature of at least +5 degrees.

As for the consistency of the cement mortar, everything will depend on the area in which it will be used. For example, for masonry you will need thick material, for pouring - liquid.

Try not to do it right away a large number of solution, especially if the composition contains wet sand. In any case, there will always be an opportunity to do the batch again.

For screed

The rules for preparing the solution depend on the purpose for which it will be used. For example, it is easier to prepare a mixture for a screed than for organizing a foundation. Crushed stone is not required here, and the proportions of the remaining components will be as follows: M400 cement and sand in a ratio of 1 to 3.

To properly prepare the consistency, follow the steps in the following order:

• lay a sheet of metal on the floor;
• pour 1/3 sand and 1/3 cement onto the surface, mix until smooth, repeat this action until the components run out;
• Make a pile from the resulting dry mixture and make a hole in it;
• Pour some water into this “container” and mix everything well.

The mixture is made as it is used, that is, after finishing one solution, prepare the next one.

For the foundation

As for preparing the mixture for the foundation, the process is more complicated, and the best solution will use a device such as a concrete mixer.

Begin the mixing process by adding water. The required amount is determined by a ratio of 1: 4. Experts recommend initially pouring less water, since it can be added at any time. When preparing the cement mixture for the foundation, it is very important to monitor the consistency. It is better if it is liquid, but water must be used carefully. If there is a need for thickness, this indicator can be achieved after the kneading process is completed.

For finishing

Cement mixture It is also used in interior decoration. The need for it appears when it is necessary to carry out high-quality plastering of the surface.

The use of components that are contained in cement makes it possible to obtain the required consistency. Please note that this job requires more solution. If there is a need to sand a small area, you can use manual mixing, but in any case, a concrete mixer will make this process faster.

In order to understand whether the consistency in front of you is correct, apply it to the trowel: it should slide off smoothly when tilted.

Application

So, the first step was to prepare the tools and all the necessary working materials to make cement, the second step was to create a solution, and the third was to use the resulting consistency in the work. It is obvious to any builder that such a solution is a material that cannot be stored for a long time after work. This is due to the fact that it has a high viscosity and hardens very quickly, which means that it further use will be impossible.

The choice of concrete proportions used for the foundation is influenced by many factors: soil parameters, expected loads, type of foundation. The basis of cement mortar is cement, sand, crushed stone or gravel and water; its properties directly depend on the quality and uniformity of mixing of the components. Changing the regulated ratios is unacceptable; the slightest errors lead to a decrease in the strength of the foundation and, as a result, the risk of destruction load-bearing structures building.

1. Required brand
2. Proportions for preparing the solution
3. What are the requirements for the components?
4. Description of the concrete preparation process

Choosing a concrete grade

The main criteria include the geological conditions of the site (relief, level and partial pressure groundwater on foundation elements, climate, freezing depth), type of foundation, presence or absence of a basement, building height and other weight loads. The limiting factor is the work budget; using high-quality types of concrete for the construction of light buildings on summer cottages is not economically feasible. The recommended minimum is:

• M400 – for houses over 3 floors.
• M200-M250 – for frame and panel buildings.
• M250-M300 – for buildings made of wooden beams.
• M300 – for low-rise buildings made of expanded clay, gas silicate or cellular blocks.
• M350-M300 - when building with brick or pouring load-bearing walls made of monolithic concrete.

The specified gradations are relevant when constructing one- or two-story houses, when adding another floor, it is advisable to choose a higher grade. The same applies to ready-made purchased solutions, especially if purchased from an unverified manufacturer. In general, the minimum permissible strength when concreting the foundations of residential buildings on slightly heaving soils is M200; when building on less stable soils, it increases.

When preparing solutions, the working measure is the mass or volume fraction of the binder; the most common and convenient ratios include 1:3:5 (cement, sand, gravel, respectively). The regulated proportions, depending on the required strength of concrete, are:

The strength of concrete is primarily affected by the ratio of sand and cement, but in addition to strict control over the proportion of dry components, the amount of water introduced is monitored. When using Portland cement, the W/C proportions are:

When building a foundation on dry soils, it is allowed to add lime or clay to the cement mortar; these components increase its plasticity. The recommended proportions when using Portland cement M400 are:

In private construction, it is inconvenient to separately determine the mass of all poured ingredients; a bucket is usually used as a measuring tool. In this case, all fillers are pre-weighed in a dry state. The W/C ratio largely depends on the moisture content of the sand; experienced developers add no more than 80% of the recommended proportion of water during mixing and then, if necessary (the consistency is not sufficiently plastic), pour it in portions. Fiber, PAD and other plasticizers are added to concrete at the very end along with the liquid; their share usually does not exceed 75 g per 1 m3.

Component Requirements

To prepare cement mortar for pouring the foundation, the following is used:

• Fresh Portland cement, ideally the release date does not exceed 2 months before the start of concreting. The recommended brand is M400 or M500.
• River sand with particle sizes ranging from 1.2-3.5 mm with admixtures of silt or clay not exceeding 5%. It is advised to check its cleanliness (fill with water and monitor the change in color and sediment), sift, and, if necessary, rinse and dry.
• Pure crushed stone or gravel with fraction sizes from 1 to 8 cm, with flakiness within 20%. When preparing concrete for the foundation, hard rock screenings are used; limestone is not suitable due to its low strength.
• Water: tap water, free of impurities and foreign particles.
• Additives: antifreeze, plasticizing, reinforcing fiber. The introduction of such impurities is carried out with strict observance proportions.

It is important to understand the principle: coarse filler is introduced into the solution not only to replace the more expensive binder, it is precisely this that imparts the necessary rigidity. The minimum compressive strength of gravel or granite screenings is 800 kgf/cm2; in its absence, concrete simply will not withstand the weight load. A mixture for a foundation without crushed stone is prepared only when constructing it from individual blocks or slabs, and sometimes for quick pouring of pile supports.

Recommended proportions of cement and sand for masonry mortars– 1:3 or 1:2. The first ratio is considered universal, the second is chosen when constructing foundations on unstable soils. In practice, this means that for one bucket of cement with a grade not lower than M400 (M500 at increased load) take 2 or 3 sifted quartz sand and no more than 0.8 parts of water. A properly prepared mixture has a consistency similar to toothpaste, to increase workability per 1 m3, 75-100 g of plasticizers are introduced ( liquid soap or other PADs).

How to make cement mortar for the foundation?

The process begins with the preparation of components and a concrete mixer; the presence of the latter is mandatory when mixing concrete for underground structures. The amount of building materials is calculated in advance according to the volume of the foundation and is purchased with a small margin. It is extremely important to carry out the filling on the same day, when self-cooking solution, all components are washed and dried in advance. Next, they are poured into buckets into a concrete mixer in the following sequence: part of the water → sand and cement → dry additives and fiber (if necessary) → coarse filler → the remaining liquid in small portions. After adding the new ingredient, the drum is turned on for 2-3 minutes, and no more than 15 minutes later the finished solution is unloaded.

There is a time-tested method of selection correct proportions, selected in the absence of data on the size of crushed stone. In this case, the bucket is filled with coarse filler, shaken several times and completely covered with water. The resulting volume of water corresponds to the required proportion of sand in the solution. After that, sand is poured into the bucket and filled with water again to determine the proportion of cement. But some consider this approach complex and outdated; the standard method of recalculation is considered more correct mass fraction into the volumetric and pouring the components into the concrete mixer.

In order to independently prepare cement mortar for pouring the foundation, it is important to select the right components, observe required proportions materials and take into account some of the nuances of mixing and pouring.

Its quality and durability depend on how correctly and in what proportions the components for the foundation mortar are selected.

Materials for the mixture

In order to make concrete for the foundation, you will need:

• water;
• sand;
• cement;
• crushed stone;
• additives (if necessary).

Water for preparing cement mortar should, if possible, not contain chemical substances(fuel oil, gasoline and others). Regular running water- what you need.

The sand should not be silty or clayey. Fatty substances create films that prevent the components from adhering to each other. Ideally, washed sand goes into the solution, the cleaner the better.

Cement is distinguished by its brand. The most common are M300, M400 and M500. The higher the grade of cement, the higher the quality of the resulting solution, that is, such specifications, such as compressive and fracture strength.

According to the construction goals and the size of the foundation, a specific brand of cement is selected.

In order to prepare a solution for the foundation, you will need water, sand, cement, crushed stone, and, if necessary, various additives.

Crushed stone should not be limestone. You should also not add gravel as a filler for cement mortar. It is better to take crushed stone. His sharp corners, the uneven edges cling to each other and thereby increase the strength of the concrete for the foundation. Cement-sand, as well as mortar based on gravel, expanded clay, and other fillers will be less durable and therefore are not used in the manufacture of concrete for foundations.

Additives are needed if you need to make a solution under special conditions. For example, when you need to make a solution in frosty weather, or the finished foundation will be partially or entirely in water and exposed to aggressive environment. Additives are mixed with water according to the instructions on the package. It is worth remembering that any additives lower the grade of concrete.

Cooking methods

There are 2 main mixing methods: mechanical (using an electric concrete mixer) and manual. Let's look at each separately.

Mechanical method

This method involves the purchase of a rather expensive tool - an electric concrete mixer. Since pouring the foundation is usually the very beginning of construction, purchasing a concrete mixer at this stage is economically justified. So, the object should have:

Device diagram monolithic foundation on a sand and gravel bed

• buckets;
• shovels;
• water barrel or hose;
• concrete mixer;
• extension cord (carrying).

Buckets are convenient for carrying sand and crushed stone and loading cement into a concrete mixer. In addition, buckets make it easy to measure the required amount of each component and maintain the correct proportions. Shovels are used to throw materials into buckets.

The capacity of the concrete mixer depends on the size of the building under construction and varies between 50-300 liters. To build a private house, a single-phase 220 volt concrete mixer will be sufficient. Larger projects, as well as industrial facilities, may require 380 volt three phase. To operate the concrete mixer itself, you may need an extension cord to supply electricity to it.

All prepared components (water, cement, sand, crushed stone) in required quantities load the concrete mixer into the bowl and turn on the apparatus. The mass is brought to a homogeneous creamy state. The solution for pouring the foundation is ready.

Manual method

To knead manually you will need:

• buckets;
• shovels and bayonets;
• capacity;
• water barrel or hose;
• hoe.

You need to pour water into the container for mixing the components (already with additives, if needed), then add sand and cement. It is convenient to mix the solution manually in a trough or old bathtub using a hoe or bayonet shovel. The mass needs to be made homogeneous, similar to sour cream. At the very end, all that remains is to add crushed gravel and mix everything again. The solution is ready.

It’s good if it is possible to pour the foundation directly from a concrete mixer or trough - this way you can save a huge amount of time and effort. If this is not possible, then the ready-made cement mortar is poured into buckets using a shovel and the foundation is poured from them.

Proportions

Cement and sand are mixed in a ratio of 1:3. The amount of crushed stone is not strictly standardized, but usually they take the same amount as sand. Thus, for 1 bucket of cement there are 3 buckets of sand and 3 buckets of crushed stone.

The amount of water is selected experimentally each time, as it depends on many factors. For example, from the humidity of sand and air. It is important to achieve the desired consistency (like sour cream) and not to overdo it with water. The thinner the solution, the lower the grade, and, accordingly, the worse the strength of the resulting concrete.

Fill

Concrete does not set well at temperatures below +8 degrees Celsius (unless frost-resistant additives were included in it), so it is better not to pour in cold weather. The quality of such concrete will be worse than that of ordinary concrete, and, alas, nothing can be done about it.

The process of concrete setting has nothing to do with drying! If pouring occurs in hot, sunny, dry weather, then there is no need to add additional water to the solution. In this case, the only correct solution would be to water the foundation for several days simply from a hose, from above, to prevent the concrete from drying out. If it dries out, it begins to burst and crack.

When building a house or gazebo on summer cottage, every owner is faced with the need to lay a foundation. This process is complex and responsible, because you need to choose the right material and calculate the ratio of components. Therefore, before starting work, you should carefully study the stages of foundation construction.

Due to its low cost and exceptional durability, concrete is considered the most popular material for pouring foundations. In this article we will look in detail at the intricacies of working with it, so that even a novice master can build a base on his own.

The composition is prepared taking into account certain proportions of crushed stone (or gravel), sand and cement. What ratio of components is required depends on the result to be obtained. Crushed stone and sand serve as fillers, cement is needed as a binder that holds the components together into a single block. If too many cavities are formed between sand and crushed stone, then the need for cement increases. To keep them to a minimum, it is important to use crushed stone different sizes: small particles will fill the cavities between large ones, and sand will fill between small ones.

Concrete hardens within a month, but this process is most intense during the first week.

Types of concrete for pouring the base

To prepare a solution for the foundation, sand is suitable, the particle size of which varies from 1.2 to 3.5 mm. Use bulk material without foreign impurities. A five percent clay and silt content is allowed, but this makes the concrete less durable.

The following experiment will help determine the quality of the composition: pour sand into a container, dilute it with water and shake the resulting solution thoroughly. If the water remains clean or loses a little transparency, it means the raw material High Quality, and if it becomes very cloudy, it contains impurities. You can also leave the container to stand for a while. If clay sediment eventually appears above the sand, it is better not to use such bulk material for construction.

Thematic material:

• Proportions of concrete for the foundation in buckets
• Foundation concrete recipe

There should also be no impurities in the crushed stone composition. The particle size is 1-8 cm.

IN construction field The following types of cement are distinguished:

1. Portland cement (the most common option, which is used in the construction of various structures).
2. Slag Portland cement (has high moisture resistance and frost resistance, but hardens more slowly).
3. Pozzolanic Portland cement (used for the construction of structures under water and underground due to its exceptional moisture-resistant properties; in air conditions it shrinks strongly and loses strength).
4. Fast-hardening cement (hardens in about 2 weeks; it is necessary to work with such material without delay, as it sets instantly, so this is not the best option for novice builders).

Thus, the most suitable material For self-filling The monolithic foundation of a house or other structure is Portland cement.

The following grades of cement are distinguished: ... PTs 500, PTs 500 D20, PTs 400 D20, PTs 400, etc. In accordance with the brand, the value of its compressive strength changes, which is determined for a concrete cube with sides of 20 cm and is measured in kg/cm2 .

Preparing the right solution

To obtain the composition of the desired viscosity, certain proportions are observed during its preparation. The ratio is 1/3/5, where 1 is cement, 3 is sand, 5 is crushed stone.

The use of additives will allow you to obtain a certain type of cement mortar: quick-hardening, hydrophobic, pozzolanic, colored, sulfate-resistant, plasticized, etc. in this case apply different brands from M 100 to M 600. But to get, for example, a mixture of M 400, it is not necessary to use cement of the same brand.

Below is a table of ratios that will help in the calculations:

If you dilute cement M 400 with four buckets of water in a ratio of 1:4, you get a mixture of M 100, and to prepare a solution of M 100 from M 500, add five buckets, that is, 1:5.

To prepare concrete grades M 300 and M 400, the weight of the components must exceed the weight of water by half.

If you need to get 1 cube of concrete (this is V cube, each side of which is 1 m), then the ratio should be as follows: half a cube of sand, 0.8 crushed stone and filler. The amount of the latter depends on the purposes for which concrete is required. Please note that the less cement the solution contains, the more mobile it will be. It is important to know that you cannot put more than 350 kg of cement on one cube (that’s 7 bags), increasing the norm can provoke destruction.

The price per cubic meter of cement varies; the higher the grade, the higher the cost.

To make concrete, use a concrete mixer, a wooden box, an iron bath or wood flooring. It is important to ensure that no debris or other impurities get into the solution. To begin with, pour in the dry ingredients - sand, crushed stone, cement, mix them thoroughly to obtain a homogeneous composition. Then slowly add water, stirring until evenly moistened. And only after that they start pouring.

Keep in mind that cement does not store for long; over time, its grade decreases under the influence of moisture. After the first month, about 10% of strength is lost, after 3 – 20%, in six months this figure reaches 30-40%.

When pouring a foundation, the most popular unit of measurement is a bucket, so few people accurately observe the correct proportions. It is not recommended to stir the mixture with a shovel, as the concrete will be inhomogeneous. Thus, losses may occur and eventually the M 100 grade will be released. But this will be enough for construction small house or gazebos.

Even if you deviate greatly from the standards for pouring a foundation, it will still be durable and will withstand heavy loads, so it will be suitable for building a house. But, according to official standards, you should take cement M 300 or M 400 to get a grade of 200 or more.

Pour the foundation when warm weather, negative temperatures provoke some difficulties. For example, you will have to heat the water and the composition itself, since they may freeze before hardening begins. And when hardening begins, without heating the concrete will begin to freeze due to the water contained in it, and the resulting ice crystals will begin to destroy the foundation from the inside.

If you follow the proportions and prepare the composition according to standards, even at home the solution will be homogeneous and as close as possible to the correct option, so don't worry about its durability.

Now you know what ratio of components is needed to prepare 1 cube of concrete. The main thing is to accurately calculate the proportions and try to follow the technology. Concrete is an easy-to-prepare composition, so the knowledge gained will help even a novice builder to easily build a foundation for a house or gazebo.