A solid foundation of the house - the key to the fact that he will have a long time. A columnar foundation is though both is the cheapest, but in the case of its proper design, it will also be a reliable support. As the calculation of a column foundation is performed, is set out below.

Briefly about the column foundation, its types and features

The foundation columnally differs from the tape that:

• suitable for buildings related to lightweight type. These include wooden houses without basement, columns, etc.;
• it is a row of supports located at the most loaded points.

Plugged foundation mainly 2 species:

1. Monolithic. It has greater strength, because Made of reinforced concrete.
2. The team consists of individual elements, so it has weak places where the seams are located. The advantage of it in the ray rate.

Based on the calculated parameters of the foundation of this species, such as the depth of groundwater, the level of freezing and the type of soil, there are two varieties of the columnar base:

1. Blowed below the level of the freezing, it is also called a swelled. On clay soils, only such a thing.
2. Made at a depth of up to 700 mm. It is called a little glare. It is advisable on sand or rocky soils.

Source data for calculation

In order to embark on the calculation, you will need the following information:

• at what depth are groundwater. It takes into account the oscillation of this parameter in different periods;
• winter temperature and information about how much the land is free. This data is in reference books;
• what type of soil refers;
• how much will approach the house and everything that is in it;
• mass of the most columnar foundation;
• wind and snow loads.

The depth of the lands in different regions of the country can be seen in the picture:

Independent definition of the type of soil

It is unlikely that someone wants to go to the laboratory and pay money for research, but such a parameter as the soil resistance depending on its type is very important, so it is necessary to determine it at least alone. We are guided by the following:

1. I dig a hole in a depth below the layer of freezing.
2. We take a little land from there, try to roll her into the ball and see what it turns out:

• from the sandy soil to roll the ball is impossible. The fact that it is really sandy is determined and visually, but the fraction can be very small. Resistance to such soil - R \u003d 2. For the sand of the middle and large fractions, this indicator will be 3 and 4.5 units, respectively;
• if you managed to form a ball, but when pressed, it immediately crumbled - the soil is a sabe, and for it the smallest resistance - r \u003d 3;
• the rolled ground is dense. Summit the ball, you will not see cracks on it. Conclusion: you have clay in your hands, it means R \u003d 3-5;
• in the case of a sublinka, the ball will also not fall apart, but the cracks will appear when pressed. For this type of soil R \u003d 2-4.

Calculation of the load on a column foundation depending on the weight of the outdoor part of the house

The calculation is possible to perform when you have already identified:

• with the material from which walls will be erected;
• with the type of roofing;
• with what furniture and household appliances are placed in the house.

To obtain this important parameter, perform the following actions:

• we summarize the loads created by walls, partitions, roof elements and objects inside the house;
• plus to the result resulting the load on the weight of the snow cover. In different places, this figure is significantly different. So, if in southern Russia it is only 0.05 tons per square meter, then in the north the proportion of snow is almost 4 times more (0.190 tons per 1 sq. M).

The calculation of a bar foundation, the example of which is shown below, is made for reinforced concrete monolithic type. Take such source data:

• one-storey house. The walls are made of structural-heat insulating a block concrete block. Wall thickness 400 mm. Density d \u003d 600;
• paul - dry bulk;
• the foundation will be arranged on plastic grinning ground;
• roof from tiles ceramic. Skat at an angle of 45 degrees. For the roof device, lags are used;
• the greatest load will have to part buildings of a larger length, because Lags will be based on them.

A columnar foundation is a rack with the following dimensions:

• the top has a cross section 35x35 cm;
• base or sole - 75x75 cm;
• poles are located with an interval of 2 m.

Load from snow

2 parameters participate in the calculation:

• regulatory load that we define on the map. Since the house is located in the suburbs, it equals 126 kg per 1 square meter. m;

• the cargo area of \u200b\u200bthe roof coming on 1 m foundation. In this case, we take not the whole foundation, but only the one part that is loaded. As can be seen from the plan, the length of these sites in the amount will be 24 m. To determine the roof area, we will need to calculate the result from multiplying 2 slot lengths for the length of the skate.

So, we calculate the length of the skate and the roof area:

• 6: 2 x Cos450 \u003d 3 x 0.707 \u003d 4.3 m;
• 2 x 4.3 x 12 \u003d 103.2 m;
• on 1 m foundation will put the weight of the roof 103.2: 24 \u003d 4.3 square meters. m.

Now we can define snow load:

4.3 x 126 \u003d 541.8 kgf.

Load created by the roof

The order is:

• the roof projection and the area of \u200b\u200bthe house are equivalent, it means that the area of \u200b\u200bthe projection is 12 x 6 \u003d 72 sq. m;
• we only have a part of 12 m are loaded, so the load on the foundation from the roof is distributed at length 12 x 2 \u003d 24 or on the plane 24 x 0.4 \u003d 9.6 square meters. m;
• from the table above we take the calculated load for ceramic tiles, located at an angle of 45 degrees. It is equal to 80 kgf per 1 square meter. m;
• so, the load on the foundation from the roof will be 72: 9.6 x 80 \u003d 600 kg per 1 kV. m.

How do the foundation of the overlapping load

This load is simply determined:

• calculate the overlap area, and it is identical to the area of \u200b\u200bthe house. 12 x 6 \u003d 72 sq. M. m;
• we multiply on the share of the ceiling material. We take data to calculate from the table:

• the load from the roof is distributed on 2 sides of the foundation. Therefore, 1 m base of the house accounts for 72: 24 \u003d 3 square meters. m;
• now we determine the load 3 x 300 \u003d 900 kgf.

Load from walls

To calculate the load, which is created on the foundation of the wall of the house, we need the following table data:

multiply:

• The height of the wall on its thickness and the load created by 1 square meter. m;
• We obtain a value expressing with what power of the wall puts on a column foundation 4 x 0.4 x 600 \u003d 960 kgf.

We summarize the load

We already have all the data for calculating the total load on the foundation:

541.8 + 600 + 900 + 960 \u003d 3001.8 kgf \u003d 30 kN.

Determination of the limit loads of the foundation on the ground

Perform the following actions:

• the result obtained is multiplied by the distance between the columns 3002 x 2 \u003d 6004 kgf;
• since the density for reinforced concrete is 2500 kg per 1 kV. m, then at the volume of our column 0.25 cubic meters. m Weight will be 0.25 x 2500 \u003d 625 kgf;

• one Status of the foundation creates a load on the Earth 6004 + 625 \u003d 6629 kgf;
• our plastic clay soil has a carrier capacity of 1.5 - 3.5 kgf per 1 square meter. See the minimum. It means that the foundation will create the maximum load of 1.5 x 6400 \u003d 9600 kgf, where 6400 square meters. cm - the area of \u200b\u200bthe foundation soles;
• the load that we obtained the calculation is 6629 kgf, therefore, the basics of the house selected are a large margin of durability, allowing, if necessary, add 1st floor.

Calculation of a column foundation under the column

When calculating the foundation under the column, we must obtain the following data:

• what a height is the foundation base;
• height of steps and their number;
• the cross-sectional area of \u200b\u200bthe subsklovnik and a glass;
• what section of the reinforcement is needed;
• all parameters of anchor bolts or mortgage parts.

Calculation This complex and responsible, so better if a professional does it. For calculation, you can use the Project Studiocs program foundations. This program, which can be purchased in Moscow in the business center "Girones" or order via the Internet, allows you to:

• with a minimum of data to obtain the maximum number of calculated parameters;
• calculate the foundation of the monolithic and team under columns both single and dual;
• the final information containing the characteristics and basic parameters is displayed in the dialog box.

Its advantages:

• it is certified;
• functional and quality is not inferior to developed abroad;
• significantly cheaper foreign analogues;
• when buying a program to it attached learning video for free.

Possible calculation of the foundation under the column and in the APM Civil Engineering system.

At the output issues:

• information about the required number of valves;
• on the number of the stages of the foundation;
• displays the geometric sizes of the columns;
• given the load on the base, will determine the thickness of the primer of the soil, etc.

Her advantages:

• fully takes into account the requirements of state building standards;

• creates models of structures;
• visualizes obtained by calculation, results;
• due to the presence of calculated and graphics tools, it allows you to solve a large list of tasks, including the calculation of a column foundation under the column.

But here it can be seen visually, how is the calculation in the APM Civil Engineering system:

Calculation of concrete for a column foundation

Suppose that such a round column parameters are known as:

• diameter;
• height;
• their number.

Calculation of concrete for a column foundation will be done like this:

• we define the area of \u200b\u200bits cross section using the formula S \u003d 3.14 x R;
• multiply the area to the height and obtain the volume of concrete for one post;
• multiply the volume for the total number of columns and will know how much concrete will be required for the device of a column foundation.

The sequence of the calculation of the foundation is popularly set out in this video: