Concrete work: basic stages

Concrete work - this is something without which it can notTo do today any building. Specialists distinguish several stages in operations of this kind, the first of which is designated as preparatory. Some sources consider it secondary, but professionals believe that it plays an important role, since includes planning work, land management, as well as the manufacture of formwork or forms (for performing tracks, for example).

Concrete works of the second stage aremixing of concrete mix, during which sand and cement are mixed separately, and gravel of the necessary size is mixed separately (if necessary). Then the mixture is poured in layers - a layer of gravel, a layer of cement-sand mixture, after which the layers are thoroughly mixed (pricked). Then the resulting mass is combined with water. If the works do not have a large scale, then water can be added from the watering can, large-scale ones require concrete mixers. It should be borne in mind that when wet, the concrete mass is reduced in volume. So, from a cubic meter of a dry mix it can turn out about 0,6 cube. meter of concrete.

If concrete works are carried out in an individualorder, it should be borne in mind that concrete can absorb additional moisture during the rain or dry out in the sun, so the third stage - styling - should be done immediately after cooking. Concrete is laid in layers no more than 20 cm, each of which is leveled and compacted by ramming. This is necessary to prevent the formation of air voids. To ensure that the timber formwork does not absorb water, it must be moistened about three hours before laying, and the boards from which it is made must be tightly fitted to each other in order to avoid leakage of the solution. The latest layer of concrete is well leveled using a board and level for alignment.

Concrete work performed from cast mass(high level of mobility) are carried out using immersion vibrators that remove air bubbles from the concrete, preventing the formation of cellularity.

Note that with the laying of the last layer of work withconcrete does not end there. Now it needs to be allowed to harden at a strictly defined temperature and humidity in order to give the necessary durability and strength. It is believed that if the mass is not properly formed, then it will crack, weathered, poorly pass the freeze-thaw cycle. To preserve water in the solution, special films or sealants are used. It is also necessary to monitor the positive temperature in the installation area, because frosts cause concrete damage from freezing.

The cost of concrete works depends on their volume: One price will be asked for the formation of the floor, another for the erection of the walls, the third for the construction of the staircase, etc. The cost usually affects the area, the usual unit of measurement is the square meter, as well as the complexity of operations. Prices for concrete work are often set for each stage of work - from dismantling any previous structures to protecting the erected foundation or other structure from rainfall.