Calculation of cement for 2 cubes of concrete. We determine the consumption of cement per cube of concrete. How much cement is required

Any person who at least once in his life had to do construction work knows that one of the most problematic tasks is calculating the proportions for cement mixing. With the wrong combination of all components, in most cases, a poor-quality mass will be obtained, which will not only quickly become unusable, but also lose its properties. In this article, we will analyze how much cement is needed per cube of concrete, depending on its brand, as well as the scope.

The first thing to remember when dealing with concrete is the strict observance of the ratio of the components of the mixture. As a rule, the ideal proportion of cement, sand and gravel is 1:3:5.

At the same time, it is important to take into account the brand of concrete used, which also affects the result of the batch. If the solution is mixed correctly, then you will get a high-quality mass, which, after hardening, will not crumble at the slightest mechanical impact.

A mixture that does not have enough hardener contained in the cement will be mobile as well as vulnerable. For example, after complete drying, such seasonal phenomena as rains, sleet or severe frosts will destroy it in a matter of months. This is especially dangerous when the concrete mass was used to build walls or foundations.

To prevent the fragility of the finished material, construction experts recommend adding 1 kilogram of cement over the norm at the mixing stage, rather than trying to save on it.

Features of choosing a brand of cement

If you are interested in how much cement is needed per 1 cube of concrete, then first of all, select the correct brand of this material. The most popular are grades 200, 300 and 400. Remember that it is not universal and is selected individually for each type of construction work. The brand of cement must necessarily be half as high as that which the finished mortar should. For example, if you are interested in the selection of concrete mix components for the foundation, then the best option would be M-200. For the production of various beams, ceilings, reinforced concrete and reinforced concrete products, cement grade 400 is actively used today. It is distinguished by its characteristics of strength, durability, and is not subject to corrosion. If you are planning the construction of walls, then it is best to pay attention to the M-300 brand material. More detailed information can be found in the table below:

The key to a quality mixture is the correct calculation of cement per cube of concrete

For the manufacture of a high-quality mixture, it is important not only to accurately calculate the most optimal amount of cement per 1 cubic meter of concrete, but also to determine the ratio of water used. It is necessary to use only pure water, which does not contain oil impurities and various chemical components. To date, a universal formula has not yet been derived by which it is possible to calculate exactly how much water is required for a concrete solution. As a rule, this becomes clear only directly during the kneading process itself, since many factors affect the moisture content of the finished mixture.

Often, to create concrete grade 400 of medium plasticity, having crushed stone impurities, approximately 205 liters of water are required for 1 cube. A high-quality solution can only be obtained using an accurate calculation of cement per cube of concrete, as well as clean sand, crushed stone and water. Many professional builders, in order to be sure of the quality of the result, carefully sift the sand using a special sieve before connecting all the components.

The bag as the main measure

In order to calculate how much cement grade 200, 300, 400 or any other is needed to prepare a quality mixture, it is important to accurately measure the amount of each of the components. Of course, builders often use various improvised tools for this, such as a ladle and a bucket. But the most convenient and best option is to measure using ordinary bags in which building materials are packed. Suppose you need 166 kilograms of cement to build a foundation. In this case, it is best to use 3 full bags with a standard weight of 50 kg, and measure the remaining 16 kg at the rate of a third of the total mass. In addition, this rule applies to other components of the concrete mix. That is why, if you are interested in how many bags of cement will be required for work, start from a simple formula that is known to all of us from the school curriculum - if you need 3 g of cement per cubic centimeter, then 333 kg (or 7 incomplete bags) respectively.

When building a house, you must have a project. It does not have to be a project made by a professional designer, in the case of self-construction of your own house, it can be your own building plan. One way or another, even before the start of construction, it is necessary to imagine what work needs to be done and in what sequence, how much building materials will be needed, and most importantly, how much it will all cost. To do this, you need to calculate the consumption of building materials, and in the case of laying the foundation, the main question is how much concrete is needed for the foundation. Concrete consumption is measured in cubic meters, not tons, so the task of the entire calculation of concrete for the foundation is to determine the volume of the foundation.

The initial data for calculating the amount of concrete for is the type of foundation (slab, strip, columnar) and its configuration. The type of foundation and parameters are selected depending on the load on the foundation. In one of the previous articles, an example was given of calculating the load ("") on the foundation from a house measuring 6 m by 6 m with one inner wall. This article below provides examples of calculating the amount of concrete for a foundation for the same house.

To calculate the slab foundation, it is necessary to know the area and thickness of the slab, the presence of stiffeners and their dimensions. In the case of a strip foundation, you need to know the depth of its laying, the width of the strip and its total length (the perimeter of the external walls and the sum of the lengths of the internal lintels under the internal load-bearing walls). To calculate the columnar foundation, you need to know the height of the columns, their diameter and number.

How many cubes of concrete do you need to pour a slab foundation?

The slab foundation is a solid foundation that fits under the entire area of \u200b\u200bthe house. Therefore, in order to find out the volume of concrete needed to pour the slab foundation, it is necessary to calculate the volume of the slab - multiply the area of the slab by its thickness. For a house measuring 6 m by 6 m, the area of \u200b\u200bthe plate will be 36 m 2. The minimum thickness of the slab foundation is 10 cm, with this thickness its volume of concrete for its pouring will be 36 m 2 x 0.1 m = 3.6 m 3. With a plate thickness of 20 cm, its volume will be 7.2 m 3, with a thickness of 30 cm - 10.8 m 3. This will be the consumption of concrete for pouring a smooth slab.

To ensure greater rigidity, slab foundations are made with stiffeners directed in the longitudinal and transverse directions of the slab and dividing it into squares. Stiffeners make the slab more resistant to deformation, they are usually made on the bottom surface of the slab, because it is easier to do so and the top surface of the slab remains smooth. To calculate the consumption of concrete for stiffeners, you need to know their total length and cross-sectional area. If the stiffeners are made every 3 m, then in the same foundation 6 m by 6 m there will be six of them - three along and three across: the stiffeners will be located at the very edges of the slab and in its middle. The length of each stiffener will be 6 m, their total length is 6 m x 6 \u003d 36 m. The height of the stiffener is usually equal to the thickness of the slab, the cross-sectional shape is rectangular or in the form of a trapezoid. The width of the stiffening rib is from 0.8-1 of its height. Thus, the cross-sectional area of a rectangular stiffener of a 10-cm slab will be 0.1 m x 0.08 m = 0.008 m 2, their volume is 0.008 m 2 x 36 m = 0.288 m 3. For stiffeners in the form of a trapezoid, the ratio of the lengths of the bases of the trapezoid is about 1.5, i.e. the smaller base is equal to 0.8-1 of the plate thickness, and the larger base is 1.5 times larger. For a plate 10 cm thick, the cross-sectional area of the stiffener will be 0.5 x 0.1 m (0.08 + 0.12) = 0.01 m 2, and the volume of such ribs is 0.01 m 2 x 36 m = 0, 36 m 3. Similarly, you can calculate the volume of stiffeners for plates of greater thickness.

The amount of concrete that is needed to pour the slab foundation is 6 m x 6 m.

How much concrete is needed to pour a columnar foundation?

To calculate the amount of concrete for you need to know the height of the columns and their cross-sectional area. The cross-sectional area of a round post is calculated using the formula S = 3.14 x R 2, where R is the radius. A column with a diameter of 20 cm has a cross section of 3.14 x (0.1 m) 2 = 0.0314 m 2. With a height of 2 m, such a column will have a volume of 0.0314 m 2 x 2 m = 0.0628 m 3. Similarly, you can calculate the volume of concrete for columns of a different size. To calculate the consumption of concrete for the entire column foundation, it is necessary to multiply the volume of concrete for one column by the number of columns.

The amount of concrete required to pour one column of a columnar foundation

How many cubes of concrete do you need to pour a strip foundation?

To calculate how many cubes of concrete are needed for pouring, you need to know the width of the foundation tape, its height and total length. The width of the foundation tape is usually from 20 cm to 40 cm and depends on what the area of \u200b\u200bsupport at the foundation should be. The height of the foundation tape is the depth of its foundation plus the height of its above-ground part (usually 40-50 cm). When laying the strip foundation to a depth of 1.5 m and the height of the above-ground part of 0.4 m, the total height will be 1.9 m. The total length of the foundation strip is the perimeter of the external walls and the length of the strip under the internal walls. For the same house measuring 6 m by 6 m with one internal wall, the total length of the tape will be 30 m (24 m external walls and 6 m one internal). If the width of the tape is 0.4 m, then the total consumption of concrete for such a strip foundation will be 0.4 m x 30 m x 1.9 m = 22.8 m 3.

What determines the consumption of cement for different solutions

The preparation of a cement mortar, the proportions of which may differ, requires strict adherence to technology and the correct determination of the ratio of components. For the application of concrete of different grades, different amounts of cement and sand are used. Remembering the proportions of cement and sand is not enough for quality construction, it is better to understand the principle.

Requires strict adherence to the technology of preparation of cement mortar

The main factors affecting the consumption:

the amount of fillers in the mixture. The greater the proportion of crushed stone, sand, the higher the consumption of cement per 1 m3 of mortar. Cement is a binder component, which is responsible for bonding all the fillers together. The ratio of bulk mixtures determines the amount of cement;
brand of cement. As the grade increases, the strength of the final structure increases. At the same time, it is worth remembering that the brand of the final mixture is much lower than dry cement, since sand is added to the composition, and gravel or slag can also be introduced;
brand of solution. The cement-sand mortar also has a division into grades. For all types of work in GOST there are recommended brands. After determining the desired brand of building mixture, you can choose the right brand of cement. For example, to obtain a mixture of M100 from M500 cement, you will need to mix 1 part of Portland cement, 5.8 parts of sand and 8.1 parts of crushed stone. If the ultimate goal is a solution of M450, a proportion of cement M500 (C:P:Sch) 1: 1.4: 2.9 will be required;

The density of cement here plays a secondary role, since it directly depends on the brand of cement, but it is necessary to know it in the calculation process.

Conclusion: how much cement is required per 1 m3 of mortar depends on the required strength of the mortar and the grade of the initial mixture.

The density of cement directly depends on the brand of cement

Variety and brands of mixtures

The introduction of the concept of "grade of cement" helps to calculate the consumption of cement per cubic meter of mortar with knowledge of the input parameters. To prepare a mortar with the same building characteristics from different brands of cement mixture, different proportions of fillers will be required. In production, cement is produced, starting from the M100 grade, but due to the low strength of the structure, the material is practically not used.

The most popular are M400 and M500 cements, but some other types have also become widespread. The choice of mixture depends on the scope of the material.

The main areas of use of brand cement:

M300 cement is used in assembly construction, as well as during the manufacture of monolithic structures;
M400 cement is successfully used in monolithic construction and during the preparation of reinforced concrete;
M500 cement is actively used in the construction of buildings or slabs that must be resistant to moisture or are in water. The areas of application of this concrete mixture are quite wide: the creation of sidewalks, the construction of asbestos-cement structures, the formation of large concrete masses and all kinds of foundations;

M400 and M500 cements are the most popular

cement M600 is used to create prefabricated structures and foundations, which create a high load;
M700 is a suitable cement grade for the construction of highly loaded and stressed structures.

Consumption rates of materials per cubic meter of different solutions

Today there are 4 main areas of concrete use: foundation, masonry, screed and plaster. In each case, special requirements are imposed on the building mixture, which makes the choice of cement and its consumption different. The highest consumption of cement per cube of concrete occurs when it is necessary to make masonry or plaster. The consumption of materials per 1 m3 of foundation mortar is somewhat lower due to the use of a large fraction of the filler: slag, crushed stone or gravel.

GOST has records of cement consumption rates per 1 m3 of mortar, taking into account the purpose of the mortar. Designation of concrete in a cube. meters is the generally accepted system of measurement.

Consumption rates of cement per 1 m3 of mortar

Consumption rates per 1 m3 using M500 cement:

on M100 - 170 kg;
on M150 - 200 kg;
on M200 - 240 kg;
on M250 - 300 kg;
on the M300 - 350 kg;
on M400 - 400 kg;
on the M500 - 450 kg.

Consumption rates of cement and sand per cube of mortar for the foundation

Calculation of cement for the foundation calculator is the easiest way to understand how much material is needed and the number of necessary components. Calculation of concrete can be made with high accuracy and manually.

To determine how much cement is needed per 1 m3 of mortar, we recommend that you follow a simple instruction:

Consumption rates of cement for the foundation

We determine the appropriate brand of cement mortar. Usually, during the creation of the foundation, it is advisable to use a solution of M100-M300. For low-level buildings, M100 is sufficient, if it is planned to build several floors - M150, and M200 and above is used in the construction of multi-storey buildings and any structures that are subject to increased strength requirements. If the foundation is being built under a wooden building, a solution of M50 is sufficient.
We select the brand of cement. For standard tasks, M300-M400 is suitable in a proportional part of cement to sand 1 to 3. When using M500 cement - 1 to 5.

How many kg of cement in 1 m3 of solution:

in M50 when using M400 - 380 kg;
in M100 when preparing concrete from cement M300 - 214 kg;
in M200 with cement M400 - 286 kg;
in M300 with M500 - 382 kg.

The data is presented if the cube includes 2-4 parts of sand and 3 parts of crushed stone.

Consumption rates of cement and sand per cube of masonry mortar

For the preparation of cement mortar for the construction of a wall, a ratio of 1 to 4 is most often used. Thus, the cement consumption per cube will be 0.25 m3 or 325 kg, and the sand consumption per 1 m3 of mortar will be 0.75 m3 or 1200 kg.

Consumption rates of cement for masonry

Table 1: Consumption of mortar on walls of different thicknesses

To calculate how many bags of cement you need, just multiply 325 kg by the consumption per cube, for example, walls in one brick - 0.221. It will turn out 72 kg of cement for laying 1 m3 of a wall, provided that there are no other components in the composition (lime, clay, etc.).

Consumption rates of cement and sand per cube of mortar for screed

The consumption of cement per 1 cubic meter of mortar is calculated according to the same rules as in previous mixtures. The recommended mixing ratio is 1 to 3. Difficulties in calculations often appear even at the stage of determining the volume of the solution, so let's look at a good example. It is necessary to pour a surface of 3x4 m or 12 m2. The layer thickness will be 30 mm.

Consumption rates of cement for screed

Calculation of cement for screed from the example:

We calculate the required volume of the solution: 12 m2 * 0.03 m = 0.36 m3.
We determine the brand of cement, the M200 solution is often used, and we use it as an example. We will cook from M500, and according to the standards, the consumption will be 410 kg.
We consider the required number of bags of cement: 410 kg * 0.36 m3 \u003d 148 kg - these are 6 small or 3 standard bags of 50 kg.
We determine the cost of sand. To do this, we multiply the specific gravity of 1 m3 of sand by the required amount of the finished mixture: 1600 kg / m3 * 0.36 m3 = 576 kg, and since the share of sand in the total solution is 75%, we also multiply by 0.75 - 432 kg of sand. Sand consumption per 1 cubic meter of solution is approximately 1200 kg/m3.

Consumption rates of cement and sand per cube of mortar for plaster

The consumption of cement per 1 m2 of plaster strongly depends on the quality of the wall covering, the required layer thickness and the number of large pits. Again, for clarity, we will give an example of calculation, remembering that a mixture of 1 to 4 is usually used. Input parameters: it is necessary to cover 60 m2 of the wall with plaster 2.5 cm thick.

Calculations of cement consumption per 1 m3 and sand:

Quantity of materials in cubes. For 1 m2, 1 * 0.025 \u003d 0.025 m3 of mortar will be required, where a fifth is cement, and the rest is sand. Using elementary mathematics, we determine that 0.02 m3 of sand and 0.005 m3 of cement will be required.
The entire wall area will require: 0.02 * 60 = 1.2 m3 of sand and 0.005 * 60 = 0.3 m3 of cement.
The specific density of cement is on average 1400 kg/m3 (fresh 1100-1200 kg/m3, and caked 1500-1600 kg/m3). We determine the consumption of cement: 0.3 * 1400 = 350 kg.
Required sand weight: 1.2 * 1600 = 1920 kg, we remind you that 1600 kg / m3 is the specific gravity of the sand.

All calculations are simple, it is only important to choose the right brand of the initial mixture and the desired brand of solution at the outlet. Everything else is easily calculated in a few mathematical steps.

The foundation is a very important and expensive element of a building. The durability and strength of a house or outbuilding depends on how correctly it is built (filled), and given that, depending on specific conditions, the cost of a strip foundation can range from 30 to 70 percent of the cost of construction, it is very important to correctly calculate how much concrete is needed for its construction.

In this case, the following factors influence the design of the strip foundation:

The relief of the land plot for the construction of the structure;
soil type;
Depth of soil freezing. Affects the amount of heaving of the foundation;
Height of standing groundwater. It also affects the amount of heaving of the foundation (linear movement in winter).

For calculations, the usual mathematical and geometric formulas are used, which are studied as part of the secondary school curriculum.

How to calculate how much concrete is needed for a strip foundation

The strip foundation is widely used by private developers in the construction of low-rise residential buildings, baths, garages, sheds, temporary buildings and other similar buildings. The popularity of the strip foundation lies in the simplicity of design and the possibility of independent calculation and construction.

To calculate the amount of concrete required to pour the foundation, you will need to calculate the volume of the foundation in cubic meters. In this regard, two options are possible. The first option - the length, width and height of the structure are the same around the entire perimeter of the "tape". The second option - the height and width of the foundation are variables.

You can calculate how many cubes of concrete you need for the foundation according to the first option as follows.

For example, having measured the length of the foundation “ribbon” (perimeter), width and height, you received the following initial data:

Foundation perimeter (L): 40 meters. Important! The perimeter is measured not along the external or internal border, but strictly in the center of the trench under the foundation;
Height(H) 1.5 meters;
Width(S) 0.7 meters.

We substitute the initial data into the formula for the volume of the parallelepiped V=LxHxS: V=40x1.5x0.7=42 m3. To fill the strip foundation, you will need 42 cubic meters of concrete.

An example of calculating concrete for a strip foundation

Let's say your foundation has a total length of 40 meters, consists of two parts that differ in width: 10 meters of tape 0.7 meters wide and 30 meters of tape 0.5 meters wide. In this case, we use the same formula for the volume of a parallelepiped, we only make two calculations: for a “piece” of 10 meters (V1) and a “piece” of 30 meters (v2). Then we summarize the resulting volumes and get the volume of concrete for pouring (V)

V1=10x1.5x0.7=10.5 m3;
V2=30x1.5x0.5=22.5 m3;
V=10.5+22.5=33 cubic meters of concrete.

How much cement is needed?

To mix concrete for pouring a strip foundation, you need to know how many components are needed: cement, sand, crushed stone and water. In the general case, for the construction of strip foundations, concrete grade M200 is used. According to GOST, M200 concrete is mixed in the following proportions of components:

Cement - 1 part:
Sand - 2.8 parts;
Crushed stone - 4.4 parts;
Water - 20% of the total volume.

Assuming that: 1 m3 of concrete weighs about 1,500 kg, 1 m3 of Portland cement weighs about 1,300 kg, 1 m3 of crushed stone 1,450 kg, 1 m3 of sand weighs 1,700 kg, to prepare 1 cubic meter of M200 concrete, you will need: 255 kg of cement, 1,127 kg of crushed stone, 714 kg of sand and approximately 190 liters of water.

Cement is the basis of the concrete mixture, it is he who binds the remaining components together. It has a direct impact on other indicators: strength, frost and moisture resistance, dosage deviation leads to their inevitable change. Another feature is the price: of all the ingredients, the binder is the most expensive, it is economically unprofitable to fill it in excess of the norm during kneading, as well as to buy it in advance (the loss of useful properties begins 2 months after release). As a result, it is extremely important to know how much cement is needed per cubic meter of concrete before starting work, and during the preparation process, fill it within the normal range according to the type and brand of mortar chosen.

The main condition is the achievement of strength properties, which, in turn, depend on the purpose of the building structure. Proportions are selected taking into account the expected class of concrete (the recommended dosage is given in the table below), its mobility, frost resistance and water resistance. In addition to the main regulatory requirements, the final indicators of the concrete solution are affected by:

Strength grade, activity, bulk density and setting time of cement.
Sand condition: grain size, humidity, presence of impurities. If the proportion of sludge exceeds 15%, careful screening, washing and drying is required, this factor is easily checked by pouring water.
Parameters of crushed stone or other large filler: flakiness, fraction size, specific gravity, degree of pollution. By analogy with sand, it must be washed and dried.
The presence of plasticizers or hardeners in the composition.

The approximate consumption of cement per 1 cube of concrete is given in the table:

Expected strength grade	How much cement is needed for 1 m3, kg	Quantity of cement in liters
M100	166	111
M150	205	137
M200	241	161
M250	300	200
M300	319	213
M400	417	278
M450	469	313

With non-strict requirements for the quality of the solution, a simple and time-tested ratio is selected: 1: 2: 4: 0.5 (cement, sand, crushed stone, water, respectively). In terms of mass, 330 kg of binder, 600 kg of sand, 1250 kg of coarse filler and 180 liters of mixing liquid are obtained. In other cases, the proportions are selected and transferred to a weight calculation (recognized as more convenient) according to the data in the table (provided that Portland cement with a quality of at least M400 is used):

Expected concrete strength grade	Share of components
Expected concrete strength grade	cement	rubble	sand	water
When using Portland cement M400
M100	1	4,6	7	0,5
M150		3,5	5,7
M200		2,8	4,8
M250		2,1	3,9
M300		1,9	3,7
M350		1,5	3,1
M400		1,2	2,7
M450		1,1	2,5
M500		1	2
The same when using Portland cement M500
M100	1	5,8	8,1	0,5
M150		4,5	6,6
M200		3,5	5,6
M250		2,6	4,5
M300		2,4	4,3
M350		1,9	3,8
M400		1,6	3.2
M450		1,4	2,9
M500		1,2	2,5

Thus, in order to determine how much cement is required for concreting, the type is first established and the volume of the structure is calculated, and based on these data, all other components. The minimum allowable brand of mortar for foundations and load-bearing walls is M200, as the number of storeys and other loads increases, the requirements increase.

Solution preparation

The quality and uniformity of the concrete mixture depend not only on the selected proportions and the degree of preparation of the ingredients, but also on their connection sequence. In private construction, two methods of self-preparation of solutions are practiced: manual and mechanized using a concrete mixer. In the first case, the binder and filler are first thoroughly mixed in a dry state (starting with cement and sand) and only then they are mixed with clean water. All components must be prepared in advance, taking into account the required volumes.

With mechanized mixing, the recommended sequence is completely different. First, about 80% of the total proportion of water is poured into the bowl of the concrete mixer, after which sand and cement are introduced in small portions, with the rotation of the drum or blades periodically turning on, and at the end, coarse-grained filler. The remaining dose of liquid is poured in in small doses, the excess adversely affects the strength of concrete.

In general, when preparing a solution, the following rules must be taken into account:

1. When laying the reinforcing cage (concreting of foundations, load-bearing walls and ceilings), an increased proportion of cement is introduced into the composition - from 220 kg per cubic meter, this is the minimum norm for reinforced concrete products.

2. The declared cement strength grade deteriorates during long-term storage; it is impossible to use a binder released more than six months ago for mixing with the same proportions.

3. The final class of concrete depends on the quality of the filler: sand, crushed stone or gravel. An increase in the proportion of cement has a positive effect on strength, but only up to a certain point: when it is added more than 400 kg per cubic meter of mortar, it will remain unchanged, and when it is backfilled over 500, it will begin to fall.

4. When preparing concrete mixtures for the foundation, crushed stone or gravel with a compressive strength of at least 800 kg/cm2 is used.

5. The total volume of the laid components individually is always higher than that of the resulting solution, this must be taken into account when calculating materials.

6. Before purchasing cement, it is worth checking not only the date of manufacture and the availability of a certificate, but also clarifying its bulk density, the recommended minimum is 1300 kg / m3.

7. To speed up the process, you need to choose a working container for backfilling (most often a bucket) and calculate how much sand and crushed stone weigh when it is completely filled and compacted.

8. Amendment (reduction of the W / C ratio) in case of overmoistening of the filler is required.

9. The values indicated in the table above are relevant when using exclusively fresh cement with a strength grade of at least M400. The preparation of concrete mixes based on a binder inferior in quality increases its share by several times.

10. There is a way to recalculate the proportions if it is necessary to use inferior as cement. The coefficients of transition to the next grade are at least 0.9, it is by this value that the proportion of binder in the concrete mixture must be increased.

11. It is impossible to obtain high-class concrete based on cement with a lower strength grade.

12. When mixing a solution for pouring a monolithic foundation, crushed stone must be added to the composition. Its optimal ratio with sand in volume terms reaches 0.8:0.5.

13. Permissible deviation in the selection of dosage per cube for cement does not exceed 1 kg, for crushed stone - 5.