Specify required dimensions in millimeters
X- foundation width
Y- foundation length
A- foundation thickness
H- foundation height
C- distance to the axis of the jumper
A- foundation thickness
H- foundation height
S- step between connections
G- horizontal rows
V- vertical rods
Z- connecting rods
The required amount of cement to produce one cubic meter of concrete is different in each specific case.
This depends on the brand of cement, the desired brand of concrete produced, the size and proportions of fillers.
Indicated in bags.
There is no need to repeat how important it is to calculate the quantity when designing a house. building materials for the foundation of a house.
After all, the cost monolithic foundation reaches a third of the cost of the house.
This service will make it easier to plan and calculate the foundation of a house. It will help you calculate the amount of concrete, reinforcement, and formwork boards for installing a strip foundation.
What you can find out:
Footing area (for example, to determine the amount of waterproofing to cover a finished foundation)
The amount of concrete for the foundation and floor slabs or pouring the basement floor (it will be fun when, due to a simple error in multiplication, there is not enough concrete)
Reinforcement - quantity of reinforcement, automatic calculation of its weight based on its length and diameter
Formwork area and quantity of lumber in cubic meters and pieces
Area of all surfaces (for calculating foundation waterproofing) and side surfaces and base
Added calculation of the cost of foundation building materials.
The program will also draw a drawing of the foundation.
I hope that the service will be useful to those who build the foundation with their own hands and construction specialists.
concrete composition
The proportions and quantities of cement, sand and crushed stone for preparing concrete are given by default as a guide, as recommended by cement manufacturers.The same goes for the price of cement, sand, and crushed stone.
However, the composition of the finished concrete greatly depends on the size of the crushed stone or gravel fractions, the brand of cement, its freshness and storage conditions. It is known that when long-term storage cement loses its properties, and when high humidity The quality of cement deteriorates faster.
Please note that the cost of sand and crushed stone is indicated in the program for 1 ton. Suppliers announce the price per cubic meter of sand, crushed stone or gravel.
The specific gravity of sand depends on its origin. For example, river sand is heavier than quarry sand.
1 cubic meter of sand weighs 1200-1700 kg, on average - 1500 kg.
With gravel and crushed stone it is more difficult. According to various sources, the weight of 1 cubic meter is from 1200 to 2500 kg, depending on the size. Heavier - smaller.
So you will have to recalculate the price per ton of sand and crushed stone yourself or check with sellers.
However, the calculation will still help you find out the approximate costs of building materials for pouring the foundation. Don’t forget the wire for tying reinforcement, nails or screws for formwork, delivery of building materials, costs for excavation and construction work.
Strip foundation - a prefabricated or monolithic foundation made of high-strength reinforced concrete blocks, which are laid along the perimeter of the future building, as well as in areas load-bearing structures. The formation of a strip foundation does not involve the use of heavy construction equipment, but at the same time it requires absolute accuracy of calculation and measurement operations. The interactive strip foundation calculator will allow you to quickly and accurately calculate the proportion of sand, cement and crushed stone when making concrete manually, the dimensions of the strip, as well as the parameters of the formwork and foundation reinforcement for a house made of foam concrete or aerated concrete.
Advantages of the online strip foundation calculator
- Saves time, nerves, effort and money when drawing up cost estimates for the purchase of building materials.
- Allows you to estimate the volume of creative actions, as well as predict the timing of the formation of a strip-type foundation.
- Competent calculation of reinforcement and concrete parameters guarantees high strength and reliability internal frame designs.
- The ability to instantly calculate parameters for a monolithic or prefabricated, shallow or deeply laid strip foundation.
- 2D and 3D visualization options allow you to clearly assess the adequacy of calculation manipulations and make the necessary corrections in a timely manner.
Problems that the calculator solves
Calculation of reinforcement for strip foundation helps determine the overall length and weight of the reinforcement cage, as well as minimum diameter transverse and longitudinal bars, the number of rows in the reinforcement belts, the pitch of the clamps and the amount of overlap. Calculations are made in accordance with the rules of SP 52-101-2003.
Calculation of concrete for a strip foundation provides information on the proportions of sand, crushed stone and cement, as well as the weight of the main building material for pouring the strip foundation. The calculation results make it possible to correctly and competently distribute the load across the structure segments.
The calculation of the formwork specifies the total length of the perimeter, as well as the area of the base and the outer side edge of the reinforced concrete strip.
An online calculator for calculating strip foundations works for you completely free of charge. If you have any questions, write below in the comments - we will definitely help you.
Note: accurate concrete calculations are carried out for dry sand and crushed stone; if they are moistened, the volume of water will be different. Here you need to experiment with the volume of water.
Foundation base width A- depends on the weight of the building, the strength characteristics of the soil under the building, etc. It is recommended to accept based on the calculation results.
The width of the roof must be increased.
H- height of the foundation. Depends on the degree of soil subsidence (the more subsidence the soil, the higher)
HC- the height of the foundation (basement) above ground level. The required formwork area depends on it. The excess level should not be less than 200 mm.
The depth of the foundation into soil subject to frost heaving (loams, clays) should be no less than the depth of soil freezing in the given region. The depth should be no less than the thickness of the plant soil layer (30-50 cm)
In underground soils, the walls of the trench are unstable and will crumble.
Horizontal rows of reinforcement are made from “working” reinforcement with a diameter of more than 10 mm, and vertical rows are made from “structural” reinforcement with a diameter of 8-10 mm of smooth or periodic section.
The pitch of vertical reinforcement is taken from the conditions of non-sagging of the working reinforcement of the upper row.
It is prohibited to insert vertical reinforcement into the ground or install it on pieces of crushed stone and other improvised objects. The reinforcement frame must either be suspended or installed on specially made concrete support cubes.
The distance between the ends of the reinforcement must be at least 15 mm.
Since a strip foundation for a house is closed loop from reinforced concrete beams, being built under all load-bearing walls of the house, choose one of the proposed eight options for a standard foundation based on how many load-bearing walls are planned in the house.
Option No. 1 is relevant if construction is planned without internal supporting walls, No. 2 if an internal supporting wall is needed, options No. 3-8 if more load-bearing walls are needed in the house.
Fill in the dimensions in millimeters:
X– The width of the foundation depends on your wishes and the possibility of construction on the site. Parameter value X take more than the width of the walls (i.e. the distance between the outer planes of the walls) by approximately 100 mm on each side to make it possible finishing. When you select the option X SP 50-101-2004 “Design and installation of foundations and foundations of buildings and structures” should be taken into account.
A shallow strip foundation is suitable for all types of soil except subsidence, peat bogs and water-saturated soils. And it is often optimal for frame, timber, and brick houses.
Y– the length of the strip foundation is determined by the length of the house.
H– The height of the foundation depends on the depth of the foundation (shallow from 0.3-1 m, buried up to 2-3 m) and the elevation above ground level. The foundation must be made below the freezing line and above the level groundwater. If it is not planned to equip auxiliary premises in the basement, then a height of about 150-300 mm above ground level is sufficient, and if the base is to be used, more. The height of the strip foundation H is taken from 0.3 m for light houses and reaches about 4 m for heavy stone ones. The key to a reliable foundation - individual project, taking into account the characteristics of the soil on the site; height of groundwater; the depth of soil freezing in your region; the weight of the house (i.e. the load on the foundation from the weight of the walls, ceilings and roof).
A– thickness of the foundation strip, i.e. the distance between the outer and inner planes of the foundation depends on the thickness of the walls being built (accepted to be 100-150 mm more). Approximate values of the thickness of the strip foundation for outbuildings (shed, bathhouse, garage) are in the range of 250-400 mm; for a 1-story light (for example, frame) house 300-650 mm; 2-storey brick house built on a foundation 650-750 mm thick.
WITH– the center-to-center distance between the foundation lintels (relevant for options No. 2-No. 8) depends on the features of your project.
Reinforcement parameters:
G– Number of horizontal reinforcing rows, for strip foundation G=2. May be more depending on size effective loads. It is recommended that you familiarize yourself with SP 63.13330.2012. Possibilities online calculator allow you to calculate up to 10 rows of reinforcement.
V– The number of vertical rods connecting the reinforcing belts to each other can be from 1 to 5.
Z– The number of connecting rods is taken from 1 to 5.
S– Step length is the distance between adjacent vertical reinforcing straps. Optimal value S 300-500 mm.
Weight of 1 m reinforcement depends on its diameter. Approximate weight of one meter different diameters iron fittings is given in the table.
| Diameter fittings, mm |
Weight of 1 linear meter of reinforcement, kg |
| 6 | 0,222 |
| 8 | 0,395 |
| 10 | 0,617 |
| 12 | 0,888 |
| 14 | 1,21 |
| 16 | 1,58 |
| 18 | 2 |
| 20 | 2,47 |
| 22 | 2,98 |
| 25 | 3,85 |
| 28 | 4,83 |
| 32 | 6,31 |
Formwork parameters:
Board thickness for assembling formwork, it is taken from 25 mm to 50 mm on the basis that the thicker the better (but also more expensive).
Board length. This parameter is usually selected around 4000-6000 mm, depending on the availability of lumber in the warehouse and the price of the formwork board.
The board is wide. For the manufacture of formwork they use edged board(possible on 1 side) 100-200 mm wide.
Installation of formwork requires care and responsible attitude of performers in order to ensure correct geometry future foundation.
It is important to strengthen the assembled formwork with wire so that it does not fall apart due to the weight of the concrete, cover it from the inside plastic film, this will prevent concrete leakage and make it possible to reuse the boards for construction purposes.
Concrete composition parameters:
Bag weight, kg– here enter how much 1 bag of cement weighs in kilograms.
Concrete proportions by weight. Approximate ratio of components for concrete mixture– for 1 part of cement take 2-3 parts of sand, crushed stone – 4-5 parts, water – 1/2 part (the mixture should be plastic and not too liquid). However, depending on the required grade of concrete, the grade of cement used, the characteristics of sand, crushed stone, the use of plasticizers or additives, the proportions may vary. Standard rates of cement consumption for the preparation of prefabricated and monolithic concrete, reinforced concrete products and structures are regulated by SNiP 5.01.23-83.
Enter prices for building materials: cement (per bag), sand (per 1 ton), board (per 1 cubic meter) and reinforcement (per 1 ton).
This construction calculator will:
- calculation of the base area of the strip foundation and the required volume of concrete for pouring it;
- calculation of the formwork area (i.e. the area of the side surfaces) and required quantity lumber for formwork of strip foundations and their price (if the height of the slab is not a multiple of the height of the board, then the number of boards is calculated taking into account covering the entire height of the slab);
- calculation of the number of bags of cement, tons of sand and crushed stone for a strip foundation and the cost of these components of concrete for pouring;
- calculation of the required reinforcement of a strip foundation, namely the number of horizontal, vertical and connecting rows of reinforcement, its length, weight and cost of reinforcement.
The calculator will also calculate the final cost of constructing a strip foundation, which will give an idea of the level of material investment in the foundation of your home and allow you to make an informed decision about the feasibility of this type of foundation. You can also calculate other foundation options using our calculators and choose the optimal solution.
IN dacha construction most often used strip base, which is rightfully considered universal. You can build it without involving specialists yourself. The main thing is to perform all calculations correctly, including required amount reinforcement for the construction of strip foundations.
A strip base is a monolithic closed reinforced concrete strip running under each load-bearing wall of a building. This type of foundation is most often used in individual construction, because has good set required characteristics and excellent price-quality ratio.
It distributes the load along the entire perimeter and prevents subsidence and deformation of the building due to the acting forces of soil heaving. Wherein . Some hobbyists do not consider it necessary to reinforce the foundation. But this process is of great importance.
After all, ultimately the strip base acquires the following properties:
- strength, reliability and durability;
- ease of installation;
- possibility of waterproofing reinforced rods.
Reinforcing steel frame is the strength skeleton of a concrete foundation
Therefore, to increase the service life of the entire building, reinforcement is indispensable. But the main thing is not only to correctly strengthen the foundation, but also to calculate it correctly.
Planning the foundation must be done with particular care, because in case of deformation, it can affect the entire building, and fixing it can be very difficult and expensive. You can calculate the amount of materials required for a strip foundation and rolled steel for it yourself, or you can use the online calculator service.
An example of calculating a strip foundation
To calculate the strip foundation, you need:
- calculate how much the house weighs without taking into account the foundation;
- determine snow and wind loads;
- choose the type of base.
- calculate the area of the foundation base, taking into account the bearing capacity of the soil.
Snow load can be calculated based on SNiP 2.01.07-85. Section 5 provides data for all areas. It is quite difficult to calculate the wind load of a strip foundation. You can use the simplified formula: (15 x h + 40) x S, where h is the height from the ground surface to the top of the building, and S is the area of the structure.
When calculating the weight of a building, it is necessary to take into account the approximate weight of furniture and equipment located in the room. For example, with a building mass of 13384 kg, a payload of 11340 kg, a snow load of 8820 kg, and a wind load of 4410 kg, the calculations will look like this. Summing up these data, we get the figure 37954 kg. You need to add 30% to it for errors. As a result, the total load on the base is 49340 kg.
In order to calculate a strip foundation, it is necessary to take into account its base length and sole area. So, if the length load-bearing wall-30 m (3000 cm), then: 24670/3000 = 8.2 cm. This figure is the minimum width of the strip base. But it is necessary to take into account that the thickness of the walls should be greater than the width of the foundation.
In order to calculate how much concrete is required, it is necessary to multiply the length of the load-bearing wall by the amount by which the foundation must be laid and by the width of the foundation. So, if the basis is sandy soil laid to a depth of 0.5 m, the width of the base is 20 cm (0.2 m), the length of the load-bearing wall is 30 m, then the calculation will look like this: 30 x 0.5 x 0.2 = 3 m3.
All materials for the foundation must be purchased with a small margin of 10-15%
Reinforcement calculation
Next, you need to calculate how much material will be needed for reinforcing work. For example, the diameter of the steel rod will be 12 mm, according to the plan in the casting there will be 2 horizontal rods, and vertically, for example, the rods will be located in increments of 0.5 m. The perimeter is 27 meters. So, 27 must be multiplied by 2 (horizontal rods) and the result is 54 m.
We count vertical rods in a similar way: 54/2 + 2 = 110 rods (108 intervals of 0.5 m each and two on each side). To account for the rods at the corners, you need to add 1 more rod, it turns out 114. If we take the height of the rod -70 cm, we calculate the length of the material: 114 x 0.7 = 79.8 m.
The easiest way to calculate the reinforcement for a strip foundation is to use online service- calculator.
Formwork calculation
If the parameters of the boards are: thickness 2.5 cm, length 6 m and width 20 cm, then the calculation will be as follows. The formula calculates the area of the side surfaces: the perimeter is multiplied by the height of the casting, and then by 2 more (the fact that the internal perimeter is smaller than the external one is not taken into account): (27 x 0.2) x 2 = 10.8 m2. Board area: 6 x 0.2 = 1.2 m2, 10.8/1.2 = 9.
So, as a result, we need 9 wooden planks, the length of which will be 6 m. To this number is added a small amount of connection boards(at the discretion of the builder). As a result: you will need 134 m of reinforcing materials and 27 linear meters of wooden blocks 20 cm wide. The example did not take into account the number of fasteners. The received data is rounded.
Calculation of reinforcement for a floor slab can also be performed using an online calculator.
Reinforcement scheme
On a strip foundation, more longitudinal tensions appear than transverse ones. Therefore, you can choose rods with a smooth surface as transverse rods, and corrugated ones as longitudinal rods. The corners bear the most loads. Therefore, when reinforcing them, it is necessary that one end of the rod goes into one wall, and the other into the other.
The reinforcement process should begin with the installation of formwork. The inside should be lined with a layer of parchment. The main purpose of the formwork is to facilitate the removal of the structure. The task of the frame is to uniformly distribute all loads on the base.
Its scheme is simple:
- Steel rods equal in length to the depth of the foundation are driven into the bottom of the trench. It is necessary that there is, on average, 50 mm from the formwork in increments of 400-600 mm;
- install stands (80-100 mm);
- 2-3 threads of the bottom row of rods are attached to them. For stands, you can use bricks, placing them on the edges;
- at the top and bottom the rows are secured with transverse jumpers to the vertical pin;
- the places where they intersect are fastened with viscous wire or welding.
When calculating and constructing a strip foundation, it is recommended to take into account the requirements of SNiP so that the structure is strong and durable
Welding work contributes to overheating of the metal and entails a change in properties. The thickness of the rods in such places also decreases. That's why Wire is often used for knitting. After reinforcement, it is only necessary to make holes for ventilation and fill the trenches with concrete mortar.
Cost of fittings
The fittings can be purchased at construction stores. Its quantity is calculated in linear meters. Therefore, in order to find out how many meters are required and calculate the final price, necessary rolled weight table. Next, we calculate using the formula: (number of metal rods in running meters) and multiply by (weight of 1 running meter of rods for the corresponding diameter) multiply by (cost of 1 ton of rods)/1000.
The weight of the reinforcement depending on the cross-section can be seen in the table:
| Reinforcement diameter | Kilogram in 1 meter | Meters to kilograms | Meters in 1 ton |
| Armature 5 | 0,187 | 5,347 | 5347 |
| Armature 6 | 0,222 | 4,5045 | 4504 |
| Armature 8 | 0,395 | 2,53165 | 2531 |
| Armature 10 | 0,617 | 1,62075 | 1620 |
| Armature 12 | 0,888 | 1,12613 | 1126 |
| Armature 14 | 1,21 | 0,82645 | 826 |
| Armature 16 | 1,58 | 0,63291 | 633 |
| Armature 18 | 2 | 0,5 | 500 |
| Armature 20 | 2,47 | 0,40486 | 405 |
| Armature 22 | 2,98 | 0,33557 | 335 |
| Armature 24 | 3,85 | 0,25974 | 260 |
| Armature25 | 4,83 | 0,20704 | 207 |
| Armature 28 | 6,31 | 0,15848 | 158 |
In great demand are fittings with a diameter of 12 mm and grooved or smooth surface. It can be sold in rods and coils.
The approximate price for 12 mm diameter per 1 m can be found in the table:
| Name | Price per meter, rub |
| A1 12 mm | 21,78 |
| A3 A400 12 mm | 21,05 |
| A3 A500S 12 mm | 21,05 |
| A3 25G2S 12 mm | 22,98 |
| 35GS 12 mm | 22,7 |
Reinforcing a strip base is not at all difficult, although it is a fairly energy-intensive process that requires financial investment. But saving doesn't make sense. By choosing the right reinforcement and calculating its quantity, you can strengthen the foundation, while extending the life of the entire building.
You can watch an example of independent calculation of a strip foundation in the video:
They can be used under different houses on various types soils, you can calculate them yourself. This does not require knowledge of higher mathematics or strength of materials. There is a method in which everything is simple, but cumbersome: you have to collect a lot of data. This calculation of the strip foundation is called “based on the bearing capacity of the soil.” But first you will need to collect the loads from the house: calculate what mass will fall on each square meter(centimeter) base. Then, choosing the width of the foundation base, select its optimal width.
Calculation method
We know for sure that the foundation is built first. But it is designed last. Its task is to transfer the load from the house. And we will know it only after we have decided on the type of all building materials and their volumes. So before you start calculating the foundation you need to:
- draw a plan of the entire building with all the walls;
- decide whether a basement is needed or not, and how deep it should be if needed;
- know the height of the base and the material from which it will be made;
- determine the type and thickness of materials used for insulation, wind protection, waterproofing, finishing both inside and outside.
For all materials used during construction, you need to find them specific gravity. It is advisable to make a table: it will be easier to work. Only after this can you begin to calculate.
Strip foundations are most often made monolithic or. Brick or rubble concrete belts are made much less often today: they are less reliable, but at the same time their construction requires large quantity material, although its cost may be less.
Conventionally, the calculation of a strip foundation can be divided into several stages:
- Determination of the load on the foundation.
- Select ribbon options.
- Adjustments depending on conditions.
Now about all the stages in more detail.
Collection of foundation loads
At this stage, the mass of all building materials that are used for construction is summed up:
As already said, by this moment a building plan with more or less accurate dimensions should already be ready. Calculating the mass of building materials used is simple: find the area on which it will be located, multiply by the specific gravity, and get the mass.
If the element being calculated is rectangular, find its area by multiplying the length of the sides. If you count in meters, you get m2. Multiplying by the thickness of the material in the same units (in meters) you get the volume in cubic meters - m3. It will be more convenient to work this way: most of the specific gravity of building materials is given in kilograms per cubic meter (kg/m3). By multiplying the found volume with the specific gravity of the material, you get the mass of the material for this plane.
Example of wall mass calculation
To make it clearer, let's give an example. Let's calculate how much a wall made of profiled pine beams 150*150 mm will weigh, with cladding made of linden lining 14 mm thick, lathing made of pine beams 50*20 mm. The wall is 4 m long and 2.8 m high.
The specific weight of the purchased pine timber (can be different) is 570 kg/m 3 , lining 530 kg/m 3 , timber 510 kg/m 3 .
Wall area: 4 m * 2.8 m = 11.2 m 2.
The volume of the timber in the wall will be 11.2 m2 * 0.15 m (thickness of the timber) = 1.68 m3.
Multiplying the volume by the specific weight of the timber, we get the mass of the wall: 1.68 m 3 * 570 kg/m 3 = 957.6 kg.
Now we find the volume of the lining on the wall: 11.2 m2 * 0.014 m (thickness of the lining) = 0.16 m3.
We find out how much the lining weighs by multiplying its specific weight by volume: 0.16 m 3 * 530 kg/m 3 = 84.6 kg.
The amount of sheathing is calculated differently: we determine how many planks are nailed. We will nail the sheathing lengthwise in 60 cm increments. You will get 5 planks 4 m long. Linear meters in total there will be 20. Now we find the volume: 20 m.p. * 0.05 m * 0.02 m = 0.02 m 3.
Now we find the mass of the sheathing: 0.02 m 3 * 510 kg/m 3 = 10.2 kg.
Now find the mass of all materials for the wall: 957.6 kg + 84.6 kg + 10.2 kg = 1052.4 kg.
We calculated that the mass of a wall with an area of 11.2 m2 will be 1052.4 kg. It turns out that one square weighs 1052.4 kg / 11.2 m2 = 93.96 kg/m2. Now, having calculated the area of all walls with such decoration, we can find their total mass. Let their total area be 42 m2. Then they will weigh 42 m2 * 93.96 kg/m2 = 3946.32 kg.
Using this method, find the mass of all the listed elements. If they have complex geometry, break them down into simple shapes and determine the area that way. There shouldn't be any problems with the rest.
In addition to building materials, the entire environment in the house will put pressure on the foundation: furniture, equipment, people, etc. It takes a very long time to calculate all this, so when planning it is assumed that per square meter of area the payload is 180 kg/m2. To find out the total payload of the house, multiply its area (of all floors) by this figure.
In most regions, snow loads on the foundation must also be taken into account. Snow loads are determined by region (see photo), their values are given in the table.
Snow loads in Russia (to enlarge the picture size, right-click on it)
But since the roofs are different, different amounts of snow accumulate on them. Therefore, depending on the angle of the slope, the following coefficients are applied:
- the angle of inclination is less than or equal to 25° - the coefficient is 1 (snow load is taken from the table without changes);
- the angle of inclination is greater than or equal to 60° - the coefficient is 0 - the snow load is not taken into account.
In all other cases (roof inclination angle from 25° to 60°), values are selected from 0 to 1 (a graph is drawn and the coefficient is determined from it).
Snow loads in Ukraine (to enlarge the picture size, right-click on it)
Example: let the snow load in the region be 180 kg/m2, the total roof area is 65 m2, the roof slope angle factor is 0.82 (tilt angle is about 30°). We find the snow load: 65 m2 * 180 kg/m2 * 0.82 = 9594 kg.
This load will need to be added to the weight of the house and its payload.
Calculation of strip foundation: determining the width of the sole
When calculating a strip foundation, it will be necessary to determine two of its parameters:
- + base height = height;
- tape width;
The third - length - is known. This is the sum of the lengths of all the walls under which the foundation will be laid.
Let us accept that the depth of the foundation for our conditions is below the soil freezing level, the height of the base is 20 cm. The soil freezes in our region by 1.4 m. According to recommendations, the foundation should be 15 cm below the freezing level. We get overall height: 1.4 m + 0.2 m + 0.15 m = 1.75 m.
Select the width of the foundation depending on the material and the distance between the walls (to enlarge the size of the picture, right-click on it)
Foundation load calculation
Now you need to find the force with which the house will press on the foundation. To do this, divide the total mass of the house (mass of all elements + payload + snow) by the area of the foundation.
We find the area of the strip foundation by multiplying its length by the width selected in the previous paragraph. Then we divide the total load from the house by the area of the foundation in square centimeters. We get the specific load for each square centimeter of the strip foundation.
Example. Let the load from the house be 408,000 kg, the area of the strip foundation (length 4400 cm, width 30 cm) - 132000 cm 2. Dividing these values, we get: 3.09 kg of pressure per centimeter.
Now it is necessary to find out whether the soils under the base of the foundation will withstand this value. Any soil can withstand some pressure. These values are calculated and entered into the table. We find the type of soil under the base of the foundation (determined by geological research) and look at its specific bearing capacity.
Bearing capacity of soils - compare the found load from the house with the standard load for your soil
If load bearing capacity the soil is greater than the load from the house, everything is chosen correctly. If not, adjustments need to be made.
Adjusting parameters
If the load transmitted through the strip foundation is large for these soils, there are two options: use lighter materials during construction or increase the width of the strip.
Changing a material is very labor-intensive: often a change in one material entails a chain of changes in the parameters of a number of others. As a result, the mass calculation has to be redone. Because more often increase the thickness of the tape in the foundation. This increases and decreases the specific load. But a strip foundation that is too wide (wider than 60 cm), especially if it is deep, is not economically profitable: there is a lot of material consumption and labor costs. In this case, it is necessary to compare the cost of several types of foundation.
After changing the width of the tape, do not forget to recalculate its mass and adjust the mass of the structure accordingly.
How to calculate the cubic capacity of the foundation
It is better to take into account the mass of the foundation by calculating its volume: this figure will be useful to you when pouring the foundation: you will know how much concrete to order or how many materials you will need to purchase.
All initial data are already known: height, width and length of the tape. You multiply them and you get the cubic capacity of the foundation.
For example, let’s calculate the volume of the foundation for the previously calculated strip: length 44 m, width 30 cm (0.3 m), height 1.75 m. Multiply: 44 m * 0.3 m * 1.75 m = 23.1 m 3 . In fact, the consumption will most likely be a little more: about 25 cubic meters. Use this figure as a guide when ordering concrete.
