At the beginning of construction work, owners of summer cottages have to deal with terms that they had not heard before. For example, many are interested in what BSG concrete is. Deciphering the abbreviation is simple - these are concrete mixtures, ready to use.
That is concrete, which is delivered directly to the construction site in finished form. This differs from BSS - dry concrete mixes. They still need to be diluted with water in a certain proportion to get the necessary material.
What represents
When BSG concrete is needed, the decoding of which indicates that it is a ready-made mixture, the customer needs to contact the manufacturer directly. In such cases, the company delivers the mixture using concrete mixers. This is a technique equipped with appropriate equipment that allows you to maintain the solution in a certain condition until it arrives at the site.
The composition of the BSG is a mixture of classic ingredients - cement, sand, gravel, water. The proportions depend on what characteristics the final product should have. Also in BSG there may be special additives to increase the operational characteristics of the material.
Decoding BSG concrete means that the mixture is already ready, and the customer cannot control the process of its production. However, this does not mean that everything is left to chance. The entire production process is still controlled.
The company uses a formulation that meets the requirements of GOST for such mixtures. Concrete is made from high-quality raw materials, the ingredients are taken in exact proportions, which allows you to get a mixture with the specified characteristics, that is, its viscosity will meet the standards, and after solidification, the mixture will turn into a monolith that can withstand all regulatory loads.
Main advantages
BSG are used in various fields, both for the construction of residential buildings, and for industrial construction. Of course, there are some brands of concrete that have specific characteristics and cannot be produced using such technologies, but in general BSG is a fairly wide category of materials.
The decoding of the concrete BSG is quite long. Often it is called ready-mixed concrete. The main advantage is high quality. At the construction site, it is almost impossible to achieve such characteristics. Indeed, for this it is necessary to ensure the protection of all ingredients and fillers from contamination, to maintain a stable temperature, to achieve exact compliance with the dosage for each ingredient.
All these are very difficult tasks. Not to mention the fact that from the very beginning it is necessary to select high-quality basic ingredients and mix them in a certain sequence.
Types of BSG
For the classification of ready-mixed concrete, several criteria are used. They are divided into groups depending on the aggregate used, the density of cement, the structure of the material, as well as its strength.
From this point of view distinguish:
- lightweight concrete;
- concrete mixtures BSG heavy concrete, and they are both ordinary and especially heavy;
- ready-made concrete for social purposes.
The choice of a specific variety depends on what tasks are set by the developer.
Grades of ready-mixed concrete
Do not confuse the brands of concrete and its types. Manufacturers, as a rule, indicate in their catalogs or price lists the full marking. That is, they write not just "BSG V15 concrete", the decoding of which gives only one indicator of strength. They can write, for example, "concrete M350 B 25 P4 F200 W8", and here indicators such as its strength, frost resistance, mobility and even water permeability are already presented.
This is not an advertising move. There is GOST, concrete mixes BSG of heavy concrete B15, light or even special purpose must be fully marked. At the same time, M is the grade of the material, P is its mobility, F is frost resistance, and W is water resistance. At the same time, B is a class, and this is not the same as a brand.
The aforesaid can be considered as an example. M200 or M350 are just average indicators of compressive strength (even a special press is used to determine them).
Theoretically, the more cement is contained in the mixture, the more durable the concrete will be. Therefore, the numbers that are indicated after the letter M say how much cement is contained in concrete. Accordingly, it is believed that the M50-M100 grades are concretes with a low cement content. Then come the mixture with an average. Finally, the M500-M600 grades have the highest cement content. Their strength is higher, and the price too.
Class
In a simplified form, we can say that the brand of concrete is its rounded average compressive strength, expressed in kgm / sq.cm. And the class is guaranteed strength in megapascals.
For example, an email comes up: "Concrete BSG V15 P3 NKSCh." This will mean that the guaranteed strength is 15 MPa. If you translate into units of measure of average compressive strength, you get 153. That is, it roughly corresponds to the brand M150 or even M200.
Previously, concrete was only labeled. Now in the normative documents only the class should be reflected, but many sellers continue to indicate the brand or write both.
Frost resistance
Frost resistance of concrete is also an important indicator. It reflects the number of freezing and subsequent thawing cycles that a particular type of material can withstand without losing its operational characteristics and without deforming.
This indicator in the marking is indicated by the Latin letter F. The numbers after it indicate how many cycles the concrete will last.
For example, F50 - 50 cycles. It is logical to assume that it means 50 years, but this is not so, only the cycles themselves are taken into account. Therefore, the higher the score, the better.
For areas with severe winters, it is generally recommended to choose concrete with an indicator of at least F500 and even higher.
Water resistant
The durability of the material is affected not only by its frost resistance, but also by water resistance. Of particular importance is the indicator for concrete, which is used to arrange foundations and fill the foundation in the ground. It is denoted by the Latin letter W and reflects the water pressure that the concrete will be able to withstand.
Those who buy dry mixes are interested in this indicator no less. Moreover, they still have to prepare concrete on the ground.
Those who buy concrete BSG B20 W20 do not need a recipe: they bring the mixture ready, it remains only to use it for 2 hours so that it does not lose its properties.
Where concrete of different grades is used
When choosing a concrete brand, whether it is a finished or dry mix, adhere to the following rules:
- M100 is a material that can be used to prepare the foundation for paving, and to fix the curbs, and for the installation of the substrate when the concrete foundation is poured.
- M150 is also most often used to form the preparatory layer for the installation of monolithic foundations. It can be an independent foundation, but only for relatively small buildings. It is also used for garden paths in the plots.
- M200 is a more popular option, which is most often used in the construction of full-fledged foundations of various types - not only tape, designed for a relatively small load, but also monolithic or pile. It is used for screed devices where high loads are applied to the floor. Also needed when erecting ramps and stairs. Very popular in private low-rise construction.
- M250 has a similar scope, but is used much less frequently. But it is indispensable for the installation of monolithic foundations of high strength.
- M300 is a brand that is used in construction for a variety of purposes. It is needed for the production of reinforced concrete slabs, finished staircases, it is taken for the construction of concrete fences, etc.
- M350 - already higher strength. Such a mixture is suitable even for floor slabs that can withstand significant loads.
Bridge structures are made of concrete grade M400. Found on the market and concrete M500. But it is a very high strength. Material is rarely used in housing construction - it is mainly used in the construction of dams, the construction of bank vaults, etc.