Building Materials

Cement-sand mortar - we master the technique of preparation

What is a cement-sandy solution?

The main binder in most mortars is cement. This material is truly universal. Mixtures based on it have a high level of plasticity and strength, so it is so popular in construction. Cement-based mortar is used for the erection of brick walls, plasters of internal and external surfaces, for the production of concrete and the pouring of floors.

In its composition, in addition to cement, there are various small fillers, such as sand or small gravel. In some cases, special additives are added to such a mixture. The quality of the components and the technology of preparation depends on how well the solution will meet certain requirements. To violate the instructions on which a cement-sand mortar is made for plastering is not recommended, as this can lead to the destruction of building structures.

How is the cement-sand mortar made?

Cement-sand mortar, the composition of which is strictly regulated, is very popular in the construction industry, sinc

e in the manufacture of various reinforced concrete structures, pure cement is practically not used. How does the preparation of cement-sand mortar take place, and what is needed for this?

First dry components are mixed. Then water is added to the mixture in small portions. Its required volume is determined by experience. Usually the consistency of the solution should resemble thick sour cream. After preparing the mixture, it is allowed to stand for 15 minutes, after which it is re-mixed.

Due to the fact that the cement slurry quickly sets, do not immediately prepare large volumes of the mixture. In particular, this applies to plastering works, where the plasticity of the working mass plays a decisive role. For finishing surfaces, the mixture is prepared in a ratio of 1: 5: 2, where the third component is lime milk.

For mixing small volumes, mixing of components can be done with a mixer or electric drill with special nozzles. Stir it carefully so that no lumps remain in the mixture. Use the solution immediately after preparation, for no more than half an hour , because after the expiration of this period, the solidification of fine particles begins which will not be possible to dilute with water.

Hardening and consumption of cement-sand mortar

Special attention should be given to the timing of the use of cement, since it depends not only on its consumption, but also on the strength of cast-in-place casting or masonry. Specialists strongly recommend the use of high-quality materials for the preparation of solutions, the period of use of which has not yet expired.

The hardening of a cement-sand mortar occurs as a result of the interaction of cement grains with water, during which a gel forms, which subsequently becomes stone. It should be taken into account that decreases the temperature of the process during the process , and after the thermometer has dropped below 0 ° it almost completely stops.

With regard to the amount of material consumed per unit area, for example, when plastering walls, surface quality plays an important role, which primarily determines the thickness of the finishing layer. For example, you can calculate the consumption of cement-sand mortar, based on the following values:

if a solution prepared in the proportion of 1: 3 is used, then the cement consumption will be 0.005 m3, and the sand - 0.015 m3.Consequently - to apply the plaster for one square meter of area you need 0.02 m3 of cement-sand mortar.

It should be noted that only very average values ​​are given in the calculations, since much depends not only on the quality of the materials, but also on the qualifications of the plasterers.