The main objective of the foundation is the transfer of load from the building to the soil. Therefore, the collection of loads on the foundation is one of the most important tasks that must be solved before the construction of the building begins.
What to consider when calculating the load
Correctness of calculation is one of the key steps in construction, which must be solved. In case of incorrect calculations, most likely, under pressure from the loads, the foundation will simply settle and "go underground." When calculating and collecting the loads on the foundation, it must be taken into account that there are two categories - temporary and permanent loads.
- The first is, of course, the weight of the building itself. The total weight of the structure consists of several components. The first component is the total weight of the floors of the building for the floor, roof, floors, etc. The second component is the weight of all its walls, both load-bearing and internal. The third component is the weight of the communications that are laid inside the house (sewage, heating, water supply). The fourth and last component is the weight of the decoration elements of the house.
- Also, when collecting loads on the foundation, it is necessary to take into account the weight, which is called the payload of the structure. This paragraph refers to the entire internal structure (furniture, appliances, residents, etc.) of the house.
- The third type of load is temporary, which is most often referred to as additional loads resulting from weather conditions. These include a layer of snow, loads in strong winds, etc.
Foundation load collection example
In order to accurately calculate all the loads that will fall on the foundation, you must have an accurate plan for the design of the building, as well as know what materials the building will be built from. In order to more clearly describe the process of collecting loads on the foundation, we will consider the option of building a house with an inhabited attic, which will be located in the Ural region of the Russian Federation.
- One-storey house with inhabited attic.
- The size of the house will be 10 by 10 meters.
- The height between the ceilings (floor and ceiling) will be 2.5 meters.
- The outer walls for the house will be built of aerated concrete blocks, the thickness of which is 38 cm. Also, from the outside of the building, these blocks will be covered with 12 cm thick hollow facing bricks.
- Inside the house there will be one load-bearing wall, the width of which will be 38 cm.
- Above the base of the house will be an empty ceiling of reinforced concrete material. From the same material will be arranged and the ceiling for the attic.
- The roof will be of the rafter type, and the roof will be made of corrugated board.
Calculation of loads on the foundation
After the collection of loads on the foundation of the house has been made, you can proceed to the calculation.
- The first thing to calculate is the total area of all floors. The size of the house is 10 by 10 meters, which means that the total area will be 100 square meters. m (10 * 10).
- Then you can proceed to the calculation of the total wall area. This value also includes places for openings for doors and windows. For the first floor, the calculation formula will look like this - 2.5 * 4 * 10 = 100 square meters. m. Since the house is with an inhabited attic, the collection of loads on the foundation was carried out taking into account this building. For this floor, the area will be equal to 65 square meters. m. After calculations, both values add up and it turns out that the total area of the walls for the structure is 165 square meters. m
- Next, you need to calculate the total area for the roof of the building. It will be 130 square meters. m. - 1.3 * 10 * 10.
After carrying out these calculations, it is necessary to use the table of collection of loads on the foundation, which presents the average values for those materials that will be used in the construction of the building.
Strip foundation
Since there are several types of foundations that can be used in the construction of an object, several options will be considered. The first option is the collection of loads on the strip foundation. The list of loads will include the mass of all the elements used in the construction of the building.
- The mass of the walls is external and internal. The total area is calculated excluding the openings for windows and doors.
- Area for flooring and the materials from which it will be built.
- The area of the ceiling and ceiling.
- The area of the roof truss system and the weight of the materials for the roof.
- The area of the stairs and other internal elements of the house, as well as the weight of the material from which they will be made.
- It is also necessary to add the weight of materials that are used for fasteners during construction, to equip the basement, thermal and air insulation, as well as for facing the internal and / or external walls of the house.
These few points are an example of collecting the loads on the foundation for any structure that will be erected on a support of a tape type.
Calculation methods for strip foundations
There are two ways to calculate the strip foundation. The first method involves the calculation of the bearing capacity of the soil under the base of the foundation, and the second - the deformation of the same soil. Since it is recommended to use the first method for calculations, it will be considered. Everyone knows that direct construction begins with the foundation, however, the design of this site is carried out last. This is due to the fact that the main goal of this design is to transfer the load from the house to the soil. And the collection of loads on the foundation can be carried out only after a detailed plan of the future structure is known. Directly calculating the foundation can be divided into 3 stages:
- The first stage is the determination of the load on the foundation.
- The second stage is the selection of characteristics for the tape.
- The third stage is the adjustment of parameters depending on operating conditions.
Foundation under the column
During the construction of houses, columns can be used as supports. However, it is rather difficult to calculate for this type of supporting structure. The whole complexity of the calculation lies in the fact that it is rather difficult to independently load the column foundation. To do this, you need to have a special building education and certain skills. In order to solve the problem of calculating the load on the foundation of the column, you must have the following data:
- The first parameter to consider is weather conditions. It is necessary to determine the climatic conditions in the region in which the construction is carried out. In addition, the type and power of the winds, as well as the frequency of rainfall and their strength, will be an important parameter.
- At the second stage, it is necessary to make a geodetic map. It is necessary to take into account the flow of groundwater, their seasonal displacement, as well as the type, structure and thickness of the underground rocks.
- In the third stage, of course, you need to calculate the load on the columns coming from the building itself, that is, the weight of the future building.
- Based on the previously obtained data, it is necessary to choose the right brand of concrete according to its characteristics, strength and composition.
How to calculate the foundation for the column
When calculating the foundation for the column, it means calculating the load per square centimeter of the area of this foundation. In other words, in order to calculate the necessary foundation for the column, you need to know everything about the building, soil and groundwater that flow nearby. It is necessary to collect all this information, systematize it, and based on the results obtained, it will be possible to fully calculate the loads on the foundation under the column. In order to have all the necessary information, you need to do the following:
- It is necessary to have a complete building design with all communications that will take place inside the building, as well as know what materials will be used for the construction of the building.
- It is necessary to calculate the total area of one support for the building.
- It is necessary to collect all the parameters of the building and on their basis to calculate the pressure that the structure will exert on the pillar type support.
Foundation edge
The edge of the foundation is the upper part of the supporting concrete structure, which accounts for the main pressure from the structure. There is a certain sequence by which it is necessary to collect the loads on the edged foundation, as well as their further calculation. In order to determine the load on the edge, it is necessary to have a plan of the typical floor of the building, if it is a multi-storey building, or a typical plan of the basement, if the building has only one floor. In addition, you must have a plan of longitudinal and transverse sections of the building. For example, in order to calculate the load on the edge of the foundation in a ten-story building, you need to know the following:
- Weight, thickness and height of a brick wall.
- The weight of multi-hollow reinforced concrete slabs that are used as floors, and also multiply this number by the number of floors.
- Partition weight multiplied by number of floors.
- It is also necessary to add the weight of the roof, the weight of the waterproofing and vapor barrier.
conclusions
As you can see, in order to calculate the load on the foundation of any type, you need to have all the data about the building, as well as know a lot of formulas for the calculation.
However, at present this task is somewhat simplified by the fact that there are electronic calculators that perform all the calculations instead of people. But for their correct and productive work, it is necessary to load into the device all the information about the building, about the material from which it will be built, etc.