professional builders recommend the use of several types of concrete, ranging from M100 (strength of 7.5 MPa) to M700 (the same figure of 50 MPa).And it is necessary to orient the basis of several parameters - the load on the base of the structure which defines the bearing capacity of the building material;the degree of water resistance, depending on the depth of groundwater in relation to the foundation;Other design features and its foundation.The latter are determined directly by the architect in charge of the project and familiar with all the features of construction.
So the brand M100 and M150 is commonly used to lay the foundation for the ribbon-type soils, characterized by a weak flowability
, as well as in the case of filling the bases on an average or small depth.Typically, this frame or wooden structure.In turn, the M200 and M250 classes are applied, if necessary, fill bored piles buried in the foundations of a belt type or for fixing soles for further installation of the pillars on heaving soils types.
Stronger brand of concrete - the M300 and M400 - are used in the need to build with monolithic grillage or floating slabs.Their bearing capacity is much greater than that of the previous classes.Usually such construction materials used in the construction of multi-storey buildings made of brick, concrete and blocks of cement.
The above classes are "easy" type and brand M500, M600 and M700 are considered to be more durable and expensive.When building a cottage or country house, even in the 3-4 floors will be enough M300 and M400, and the other three - for the industrial and high-rise buildings.In particular the works they did not need at all.Builders also do not recommend to overdo it in the class of the concrete, which can be calculated as accurately as possible, otherwise the construction estimates will be heavily congested and the customer will incur unreasonable expenses.
calculation of the total load on the foundation of the structure should be maintained, based on the total weight of all of its structural elements.Therefore, to accurately determine future load is necessary to calculate the density of the materials used for the entire capacity volume to the weight of the structure.Moreover, it is best not to do it yourself, and ask for help to the architect.