Aerated concrete - one of the types of cellular concrete, which is characterized by high technical characteristics, while its price is very budget. This building material can be easily made independently using special equipment.
Independent production of aerated concrete can be of help not only for low-rise individual construction, but will also make it possible to open your own business.
These building blocks are very popular because they have the following properties:
- low density, which is almost five times less than that of classical concrete and three times less than that of brick;
- water absorption is about 20%;
- thermal conductivity is 0.1 W / m3;
- withstands more than 75 cycles of defrosting / freezing (and this is 2 times higher than the rate of a brick);
- high compressive strength allows the construction of two- and three-story houses;
- excellent sound insulation due to the porous structure;
- high fire resistance class;
- it is easy to work with material - to cut, hammer in nails;
- safe for both humans and the environment, as there are no harmful components in the composition;
- it is possible to create a cast cast structure based on aerated concrete blocks.
Production of building gas blocks is within the reach of even a novice. The whole benefit of independent work is high productivity, a simple manufacturing scheme, affordable and inexpensive materials for mortar, and the result is a building material of very decent quality with excellent technical characteristics.
Equipment and technology
There are several options for the type of line for the production of aerated concrete blocks , depending on the volume and placement conditions.
- Stationary lines. Placed to produce from 10-50 m3 blocks per day. For the operation of such equipment 1-2 workers are required.
- Lines by type of conveyor. About 150 m3 are produced per day, which ensures regular large volumes of production.
- Mobile installations. They are used for the independent manufacture of aerated concrete blocks anywhere, including directly at the construction site.
- Mini lines. This is an automated complex for the production of up to 15 m3 per day of aerated concrete blocks. The installation itself occupies about 150 m2. For the line to work, 3 people are needed.
- Mini-factory. This line is capable of generating gas blocks up to 25m3. The work of 3 workers is also required.
The most profitable and reliable is stationary equipment, since all the difficult stages are automated and manual labor is not necessary all the time. These lines use a mobile mixer, a special complex for preparing and storing the solution, heating water and a conveyor for feeding components to the dispenser. Stationary lines are productive (up to 60 m3 of finished blocks per day), but require large areas (about 500 m2) and are very expensive to install.
The producer prices of these lines in Russia start from 900 thousand rubles, while equipment of foreign manufacture will cost even more.
Conveyor lines implement a fundamentally different production model - the batcher and aerated concrete mixer do not move, only forms move. The process is completely autonomous, but due to high production rates it will be difficult to service such a process on its own - it will take 4-6 people. Placed on an area of 600 m2, its cost starts from 3,000,000 rubles. This option is suitable for those who plan to produce blocks for the purpose of their further sale.
Mobile lines are the best option for independent production of blocks for individual construction. The main advantage is the compactness of the equipment, the machine occupies only 2x2 m2. It can be placed in any convenient place: on a construction site, in a garage and even at home. The line consists of a compact mixer, compressor and connecting sleeve, which allows you to fill several forms at once. The equipment is maintained by one person. Prices for mobile installations do not exceed 60 thousand rubles and consume relatively little electricity.
Mini-lines can be stationary and conveyor type. Such plants are manufactured by the Russian companies Intechtech, Kirovstroyindustriya and Altaystroymash. The equipment of different manufacturers may vary slightly, but the basic components (mixer, machine for cutting blocks and molds) are for all models. They can occupy an area of 10 to 150 m2. It will also be necessary to organize a separate place for drying gas blocks. Mini-factories very often act as a launching pad for those who decide to manufacture and sell aerated concrete blocks. Most domestic manufacturers of this equipment do not equip it with autoclaves. However, in the first stages you can do without it. It can significantly reduce the drying time of the blocks and increase the daily output of the plant.
How to make at home?
It is very profitable to produce aerated concrete blocks not only for individual needs, but also for the sale and organization of a small business. Raw materials and tools for the manufacture of this building material can be purchased from hand, in specialized stores or directly from the manufacturer.
Some craftsmen independently make molds for blocks, which saves on their purchase.
There are two ways to make aerated concrete: using an autoclave and without it. The first option involves the purchase of special equipment in which a "baking" of aerated concrete blocks occurs under high pressure and temperature. Due to this effect, tiny gas bubbles appear in the pores of the concrete, which improve the technical characteristics of the material obtained. Such blocks have greater strength and durability. However, this method is not suitable for home use, since the autoclave is not cheap, and also due to the fact that it will be difficult to organize the technology on its own.
Therefore, for the manufacture of blocks with their own hands, the second method is suitable, without the use of autoclave equipment. With this option, the drying of aerated concrete takes place in vivo. Such blocks in terms of strength and some other characteristics are slightly inferior to autoclave blocks, but are quite suitable for individual construction.
For an independent installation of an aerated concrete plant, the following tools will be required:
- molds for concrete mix;
- concrete mixer for solution preparation;
- metal string.
You can also purchase special equipment that independently doses and prepares the mixture - this will significantly speed up the process of material production.
The technology of independent production of aerated concrete blocks has three mandatory stages.
- Dosing and mixing dry components in the required proportion. At this step, it is important to accurately follow the selected dosage, since when changing the ratio of components, concrete with different technical characteristics can be obtained.
- Adding water and mixing the solution until smooth. At this stage, the pores formed in the mixture should be evenly distributed, so it is advisable to use a concrete mixer.
- Form filling. Special compartments are only half filled with the solution, since in the first few hours the active formation of gas bubbles continues, and the mixture increases in volume.
Then, after 5-6 hours after filling in the forms, the excess mixture is cut off from the blocks with a metal string. Then the blocks remain in the molds for another 12 hours. You can leave them at a construction site or indoors. After preliminary solidification, the blocks can be removed from the containers and left to dry for several days and only then be stored.
Aerated concrete gains final strength 27-28 days after manufacture.
Forms and components
An important step in the independent manufacture of concrete blocks is the selection of suitable forms.
Containers for pouring aerated concrete may be as follows.
- Collapsible. You can remove the sides at any stage of solidification of the block. These designs require additional physical strength.
- Caps. Removed completely with the help of mechanized systems.
The material for making the molds can be different: metal, plastic and wood. The most popular metal containers, as they are distinguished by their durability and strength. They are produced in two types, depending on the volume (0.43 and 0.72 m3). Whatever the recipe was chosen for the manufacture of blocks, the raw materials required are the same.
The components for the production of aerated concrete are:
- water (flow rate 250-300 l per m3);
- cement (consumption 260-320 kg per m3);
- sand (consumption of 250-350 kg per m3);
- modifier (2-3 kg per m3).
The raw materials for the production of blocks have some requirements. Water should be of medium hardness with a minimum salinity. Cement for the mixture must comply with GOST. Portland cement brands M400 and M500 should be preferred. As a filler, not only river or sea sand can act, but also ash, waste slag, dolomite flour, limestone. If sand is used, then it should not contain organic inclusions, a large amount of silt and clay. The smaller the fraction of the filler, the smoother the surface of the blocks will be. As a modifier, in order to accelerate the maturation of aerated concrete, gypsum-alabaster, calcium chloride and water glass can act.
DIY production of concrete blocks is a long, but not very complicated process, which will significantly reduce the cost of building materials. Subject to proportions and manufacturing technology, aerated concrete blocks are practically inferior to factory ones in their indicators and can be safely used for low-rise construction.
See how the aerated concrete is produced on a mini-line in the next video.