To build the column base capable without effort to maintain the required loadings, it is necessary to learn quantity of the required support and their section. Correctly made calculation considering all necessary factors will help with it

**It is required to you**

- - sheet of paper
- - handle
- - calculator

**Instruction**

1. The purpose of calculation is to calculate what size cargo will affect columns and to learn the total area of support. The total load is weight of all building with everything being in it: furniture, household appliances, residents. To find exact weight quite difficult, but it also is not required. It is enough to calculate approximate digit as in calculation of the basic area the coefficient of additional, unforeseen loading is put.

2. Key indicator on which other conclusions depend it is soil bearing capacity. The it is lower, the bigger area there has to be basis for the house. Soil bearing capacity, in turn, depends on the following characteristics: - soil type on construction site; - degree of its density; - saturation moisture;

3. The column base will cost by 1.5-2 times cheaper of monolithic tape. Same it is possible to carry to labor costs and material consumption. Support are exposed on all angular points and between them at distance of 1.5-2.5 m from each other. For stability of the base over columns the binding is built. Material of which it is made is of great importance for the choice of section of support.

4. For concrete or butobetonny columns 40 cm of thickness, for stone - 60 cm, for brick - 35-38 cm there are enough. Such view of the column base as pile drive, in private construction it is used seldom, generally support or are made independently, or bought for the plants. Self-made columns amplify reinforcing bars with a section of 10 mm. Support can be as rectangular shape, and with broadening.

5. Calculation of admissible section of column - prerogative of special programs as in them large number of coefficients is put. It is the soil resilience, lateral pressure on support, coefficient of maximum voltage in the soil under base of foundation, the maximum ordinate of pressure of support and is a lot of others. For the private developer it is simpler to choose for himself type of column which he will establish and to make calculation of quantity of support which will be able to maintain building weight most effectively.

6. Support parameters are Let's say chosen: section 40/40 with broadening of 80 cm. At first it is required to calculate total load which will affect soil (the weight of the building and everything, in it being) - M. The shore load has to exceed building weight on 1.5. Therefore M*1.5. To these data it is necessary to add the weight of one column. Thus, we will receive the digit meaning base loading (together with construction) on soil. Further, bearing capacity of one support proceeding from the set parameters is calculated: section 40/40. This indicator is defined proceeding from coefficients of soil bearing capacity on construction site. In order that to find it, it is necessary to decide on soil type.

7. Further, the supporting surface of one column is calculated: 80*80=6400 cm2. Then we pay attention to the soil bearing value found earlier. If it corresponds 1.5, then calculation is as follows: 6400 cm "" 1.5=9600 cm2. so we find ultimate load of the basis on soil. This size has to be more than earlier found digit of total load. It was necessary to separate this digit into the found indicator of bearing capacity of one support and to be discharged exact quantity of the columns demanded to installation.