The strip foundation is used in cases where the walls of the structures are built of heavy materials, such as concrete slabs, brick, stone. It is a concrete tape around the entire perimeter of the building.
The columnar foundation is used in the construction of structures with light walls representing, as a rule, structures of light metals and glass. He perceives and transfers pressure on the ground, significantly exceeding the similar to the strip foundation.
There are brands for both cement and concrete, and they vary. The meaning of the concrete brand will always be less than the value of the brand of the source cement. For example, to make concrete of the M200 brands, we must take the cement of the brands M300, M400.
Before starting the preparation and pouring of concrete, the assembly and fasteners of the formwork are made. The composition of concrete includes the following components: cement, gravel, sand, water.
Preparation of concrete for the foundation
For the preparation of concrete, components are taken in these weight proportions: cement – 1, sand – 3, gravel – 5. Since the determination of the weight of concrete components is often unacceptable, in fact they use not weighty, but voluminous parts. The most popular and comfortable volumetric measure is a bucket.
Due to the inconsistency of concrete components in volumetric weight (a bucket of cement – 15.6 kg, sand – 19.5 kg, gravel – 17 kg), then in practice volumetric measures are taken in buckets (2 – cement, 5 – sand, 9 – 9 – gravel). Gravel can be replaced with gravel.
In the case of private construction, carried out on their own, ready-made sand-gravel mixtures (PGS) are often used. The proportions in the buckets are then as follows: 1 – cement, 5 – PGS.
In industrial construction for the manufacture of concrete, concrete mixer is used. First, cement is loaded into it, which is poured with water, and other components are added to this preliminary solution. If in the process of control it is revealed that the concrete is too thick, it is diluted with water. But it should be remembered that excess water reduces the brand of concrete, and, therefore, all its indicators. Concrete is ready for pouring into the formwork when it acquires a homogeneous consistency and plasticity.
If you need small volumes of concrete, as in the case of private construction, it is prepared manually. To do this, a flat limited surface is selected, on which sand, gravel and cement are poured and water is added. The resulting solution is mixed with a shovel until it is fully cooked.
Concrete should be used no later than two hours after its preparation.
When the list is compiled, further events will develop depending on who will make repairs: you or a construction team. In the second case, you only need to explain to the workers what is required of them, as well as buy the necessary building materials. This method saves your time, but requires more money. In the first case, if you do the repair, you first need to learn all the necessary construction operations in order to clearly understand what you are doing. The Internet can help in this. For example, Read here about repairing a house here .
