There are quite a lot of debates about which aerated concrete is better - autoclaved or non-autoclaved. Manufacturers lead comparative characteristics, specialists conduct research and make calculations various designs from these materials. But one thing remains unchanged: it is quite possible to master the technology for making non-autoclaved foam concrete at home, and autoclave blocks can only be purchased.

What's happened Not autoclaved aerated concrete? This is the same foamed concrete, but hardened under normal conditions - without overpressure and with standard thermal and humidity treatment. It differs from “kiln” concrete in that its main component acts as a binder. For aerated concrete using a non-autoclave curing method, it is always cement; lime-containing gas silicate is obtained in autoclaves.

Sometimes blast furnace slag or gypsum is added to the composition, resulting in fundamentally new materials - gas-slag concrete and gas-gypsum, but in our country they are not in great demand.

Characteristics

Like all cellular concretes, non-autoclaved porous materials with high strength are distinguished by their low weight - 4-6 times less than that of a conventional monolith. Thanks to this, blocks from aerated concrete can be made very big size, which ensures faster work with less labor costs. This is what determined the popularity among developers that non-autoclaved and autoclaved aerated concrete has gained.

Another advantage of porous blocks is their good resistance to heat transfer - the numerous air capsules of which they are composed work as thermal insulators. Energy saving characteristics concrete is almost an order of magnitude higher than its dense “parent” and clinker bricks. This allows you to save on additional insulation, reducing construction costs to a minimum.

A pleasant bonus for everyone who is used to building on their own - aerated concrete can be processed well by any electric and even hand tools. This facilitates not only the construction of the box, but also the laying engineering systems, for which you need to cut grooves or drill holes in the walls.

Comparison with autoclaved aerated concrete

Still, it would be fairer to consider non-autoclaved concrete, comparing it with its autoclaved relative. In this section, normally hardening material has its advantages:

1. The ability to produce structures from aerated concrete of any size, up to continuous pouring into formwork for monolithic construction.

2. Simplified manufacturing scheme, which allows you to make non-autoclave products even at home.

3. Slightly higher resistance to moisture and frost, although they are far from optimal.

4. Relatively low production cost due to minimal energy consumption. The price for a cube of normal-hardening aerated concrete ranges from 2,800 to 3,200 rubles; for the same blocks from a kiln, the cost only starts at 3,200 rubles/m3.

At the same time, non-autoclaved foam concrete is inferior to gas silicate in terms of shrinkage by 7-10 times and almost twice as much in strength (class B 1.5 versus B 2.5). However, this is enough for the construction of private houses of 2-3 floors. Non-autoclaved aerated concrete has slightly higher thermal conductivity – about 0.17 W/m×°C. Because of this, the thickness of the walls has to be made 40% more.

Compound

In order to produce any amount of aerated concrete on your own, you will need to stock up on raw materials:

1. Portland cement - in solution it will take up about 50-60% of total mass. The most common brands of cement are suitable: M400 D0-D20 and M500 D0-D20.

2. Fillers – ash from thermal power plants, crushed limestone, blast furnace slag (40-50% of the total mass).

3. Blowing agent - this can be aluminum powder PAP (138-195 rubles/kg) or ready-made additives like POS-15 (150 rubles/kg). For 1 m3 of mixture you will need from 1,700 to 2,800 grams. The greater the porosity of aerated concrete is required, the higher the concentration of the blowing agent should be.

4. Modifiers - these additives are not mandatory, but they can be used to improve the characteristics of foamed concrete.

The modifiers are microsilica, calcium chloride, and semi-aqueous gypsum. Instructions for home production allow their replacement with table salt (0.2% of dry weight) or household washing powder (0.01%).

By the way, microsilica, like fly ash, introduced in a ratio of 1:10 or 1:20 to the mass of cement, slightly increases the strength class of foamed products. To zoom in specifications aerated concrete to the performance of more durable autoclaved blocks, reinforcing fibers are also introduced into the solution: basalt, polymer, asbestos.

Proportions for preparing formulations of different densities (in kg):

From the given number of components, 1 m3 of aerated concrete is obtained.

Production scheme

Foaming of a composition that has not yet hardened occurs due to the reaction of the alkaline components of the solution with the foaming agent. As a result, hydrogen is released, which forms numerous pores in the concrete body. This is the most critical stage in the production technology of a porous monolith, the flow of which will determine its final characteristics.

The manufacturing scheme itself is no different from conventional concrete work:

• preparing the solution;
• pouring into formwork;
• HME at the initial stage of hardening;
• final hardening.

In order to make aerated concrete with your own hands, you will need a regular concrete mixer, a shovel and buckets. All dry components can be weighed in a separate container before mixing in order to convert the mass proportions of the solution into volumetric ones. Only the blowing agent and modifiers (salt or washing powder) will need to be accurately weighed and divided into equal portions for each batch.

Is our quick guide will help you cook aerated concrete mixture and form it into blocks or a solid monolithic structure:

1. Mount removable formwork the right size, handle internal surfaces oil

2. In a separate container, add 50 parts water to 1 part aluminum powder, add washing powder.

3. Pour aluminum powder into the resulting composition and mix thoroughly so that no metal particles remain on the surface.

4. Pour the calculated volume of water into the mixer and start the unit.

5. Contribute required quantity filler, then add cement.

6. After 2-3 minutes of mixing, you can add lime, if it is present in the “recipe,” and aluminum suspension.

7. At the fourth minute, table salt is added, and already at the fifth minute the solution is quickly poured into the formwork.

In a month, when the concrete gains strength, it will be possible to cut off the top, dismantle the frame and make aerated concrete blocks with your own hands, cutting the monolith into pieces of the required size.

Take into account the peculiarities of the geometry of non-autoclaved concrete - during the process of foaming inside the cement paste, surfaces not limited by the formwork will heave. As a result, the so-called hump will grow at the top. Its size can reach 7% of the total volume of the structure, but this bubble will still have to be removed.

Sometimes it is necessary to speed up the hardening process of non-autoclaved pouring in order to quickly release the formwork and slightly mitigate the shortcomings of foam concrete. To do this, in the first 24 hours the structures provide a constant temperature in the range of +30-50 °C. But the level of humidity and pressure according to the instructions must correspond to normal environmental conditions. It is on these days that porous concrete gains about 50-60% of its strength.

Initially, the technology for creating aerated concrete provided for its production only in high-tech production. But over time, the demand for this material increased so much that autoclaved aerated concrete began to be used equally with similar type cellular material produced without additional heat and moisture treatment. And if an unprepared beginner dives into the abyss of a huge selection of aerated concrete, he can easily drown in the flow of information provided about it. So what is the difference between autoclaved aerated concrete and non-autoclaved aerated concrete and which one is best to buy? You will find answers to these pressing questions in our publication.

Aerated concrete production technology

Before talking about significant differences in the properties and quality of autoclaved aerated concrete and naturally cured blocks, let’s consider them component composition, which is absolutely identical:

• additive-free Portland cement grades M300, M400, sometimes M500 is used;
• clean sand of fine fractions - from 2.0 to 2.5 mm.
• water of medium hardness without chemical impurities;
• gas generator - aluminum powder or paste;
• a substance that triggers chemical swelling reactions - lime, the type, condition and dispersion of which depends on the production method;
• modifiers that improve the quality of the final product are added at will and are not mandatory components.

Another similarity that unites autoclaved and non-autoclaved aerated concrete is the principle of mortar production.

At the first stage, in accordance with the technology, the usual cement-sand mortar required consistency. The resulting mixture is distributed over the formwork. After which aluminum powder and lime are introduced into it. It is the reaction of these components that ensures the formation of gas; the solution swells, forming pores.

Further technologies diverge at the stage of curing and processing of aerated concrete. During natural hardening ready solution poured into formwork, forming blocks of the required size. After gaining strength, the products are stripped and sent to the finished product warehouse.

When using an autoclave for aerated concrete, this stage is a little more complicated. Namely, the mixture is poured into monolithic formwork. After swelling and gaining minimum strength, the aerated concrete block is cut into products of the required sizes and sent for additional firing in an autoclave, where the temperature is maintained within 200 0 C and a pressure of 10 Bar. Such conditions activate cement hydration processes to the maximum and allow excess moisture to be removed from concrete.

As a result, it turns out that naturally dried products are just a hardened expanded cement-sand mixture, when autoclaved aerated blocks during the firing process form a new synthetic component - tobermorite, which qualitatively improves the characteristics of the final product.

Properties of non-autoclaved and autoclaved aerated concrete

The resulting blocks, manufactured in two different technologies so different both in appearance and in their characteristics that even an inexperienced layman can distinguish them from each other.

External indicators

The first thing the buyer encounters when choosing is the appearance of the materials. It would seem that it makes no difference what they look like wall blocks, which subsequently still need to be plastered. However appearance– the most accurate visual characteristic that will help weed out low-quality products.

Geometric dimensions

If we compare gas blocks based on geometry, then autoclave-cured products are more accurate. This is partly due to autoclaving and, of course, cutting technology. Even GOSTs regulate deviations linear dimensions from nominal in different ways, depending on the production method used.

These data only highlight the fact that autoclaved aerated concrete has precise geometry finished products which prevents:

• freezing of walls due to thickening of the masonry seam, which compensates for deficiencies in the shape of the blocks;
• overconsumption of masonry adhesive, leading to increased costs.

Color

When purchasing blocks, pay attention to their color. Of course, it will be gray in the case of naturally hardening products and almost white in autoclaved aerated concrete. Differences in block shades and color heterogeneity indicate changes in production process, which often lead to reduced performance.

Automated equipment for the production of autoclaved aerated concrete reduces any errors to zero, which is initially considered a guarantee of quality and durability. In addition, such large-scale workshops are complemented by their own construction laboratory, in which timely testing is carried out to identify inconsistencies in technology or recipes.

Physical and mechanical properties

Aerated concrete blocks differ not only in external characteristics and color, but also in physical and mechanical properties.

Strength

Aerated concrete is represented by a wide range of strength grades - from B1 to B7.5. They are widely used not only to create load-bearing structures, but also to insulate walls. If we compare aerated concrete produced according to various technologies, then autoclave ones are more durable at the same density as non-autoclave ones.

For example, blocks with a density of D600 must have a strength class of B3.5. If for autoclaved products the indicator is met, then with naturally seasoned products the strength class hardly reaches half the norm. The situation is even worse with the strength indicators of aerated concrete produced by hand. If you want to see this for yourself, buy a block and have it tested by an independent construction laboratory. The results will be obvious.

Thermal conductivity

The thermal conductivity of aerated concrete directly depends on the density of this material. The lower the density grade of the block, the better its heat capacity properties. It makes more sense to purchase products of lower density, but with higher strength characteristics, thereby reducing the thermal conductivity of the walls.

Shrinkage

The weakest side of anyone cellular concrete– this is its shrinkage after the walls are erected. When using the wrong construction methods Cracks may appear and the plaster layer will peel off. The shrinkage processes of naturally aged aerated concrete can last up to several years, when autoclaved blocks are practically free of such a drawback, since during heat and humidity treatment they have already achieved brand strength and complete drying.

In addition, seasoned aerated concrete blocks in natural conditions are far from ideal indicators, which negatively manifests itself in the form of shrinkage. This not only leads to a violation of linear dimensions, but also to destruction of the structure.

To summarize, we can easily conclude that autoclaved aerated concrete blocks have undeniable advantages over naturally cured products. But in any case, when buying such wall material always ask for documents certifying its quality.

Autoclaved aerated concrete – artificial material, well proven in the construction of industrial and residential buildings. It is a type of cellular concrete. Since the material is becoming increasingly popular in the construction of private buildings, you should know what its characteristics are, what autoclaving is, the differences between autoclaved concrete and non-autoclaved concrete, their pros and cons.

Figure 1. Autoclaved aerated concrete

Autoclaving ensures accelerated hardening of concrete. The difference between the building material and its analogues is its higher strength.

Autoclaving is a steaming process under high temperature conditions. environment And high pressure. It flows in special metal capsules. When ready-made blocks loaded into an autoclave, the pressure is 0.8-1.3 MPa, and the temperature rises to 175 0 –191 0 C. It takes approximately 12 hours until complete hardening.

Autoclaved aerated concrete undergoes changes at the molecular level. As a result of processing, a new mineral, tobermorite, is formed. He has unique properties. main feature The difference between autoclaved concrete and non-autoclaved concrete is that the first is an artificially produced stone, and the second is a hardened sand-cement mortar.

Autoclaved aerated concrete blocks have special characteristics: composition, operational features, physical and technical parameters. In most respects, autoclaved and non-autoclaved concrete are different.

Features of masonry of autoclaved aerated concrete

When erecting buildings from material produced using an autoclave for aerated concrete, you need to know a few general rules masonry and have an idea about the features of working with aerated concrete blocks:

• To begin with, the tubs always choose the most protruding corner. This will be the place with minimum thickness layer.
• The first row is laid using cement-sand mortar.
• Then aerated concrete blocks are distributed to the remaining corners. When doing masonry, they act as landmarks. A cord is pulled between them.
• In cases where the length of the wall exceeds 10 meters, several additional ones are installed between the corner reference blocks.
• The initial row is laid out completely. If gaps arise during work, the blocks are cut to the required size using an electric saw or hacksaw.

• After a short break (2-3 hours), the first row is reinforced.
• When laying the remaining rows, glue is used mainly. It is applied with a trowel and leveled with a comb. The seams are shifted by 20%.
• Since the glue sets quickly, it is recommended to level aerated concrete blocks as quickly as possible. It is almost impossible to correct shortcomings.

Pros and cons of materials

Autoclave curing blocks have a number of advantages compared to non-autoclaved concrete:

• Strength. On walls made of autoclaved aerated concrete, it is allowed to mount shelves, cabinets, as well as objects that have a large mass. For example, air conditioners. Cellular concrete, not processed in an autoclave, cannot withstand such loads.
• High quality. Since autoclaved aerated concrete can only be produced in industrial conditions, its quality level compares favorably with non-autoclaved analogues, which are often produced using artisanal methods.
• Less shrinkage during use. The amount of shrinkage directly depends on the strength of the building material. The average value for autoclaved aerated concrete is 0.5 mm/m, for non-autoclaved aerated concrete – up to 3 mm/m.

The pros and cons of autoclaved aerated concrete are presented in the table:

Advantages	Flaws
Strength.	Absorption of moisture, which in conditions low temperatures destroys the structure of autoclaved aerated concrete.
Eco-friendly, safe for the environment.	Problems with fixing fasteners, the need to use specialized products for aerated concrete.
Fire resistance.	Fragility, which is often revealed already at the transportation stage.
Easy to cut and sand.
Vapor permeability, providing a comfortable microclimate.
Thermal conductivity, which ensures heat retention in buildings.
Frost resistance, allowing to withstand up to 150 cycles of freezing and thawing.
Resistant to mold and rot.

Overview of the main qualities of the material

Figure 2. Autoclaved aerated concrete

Taking into account the advantages and disadvantages of autoclaved aerated concrete blocks, we can highlight the main properties:

• Strength. Autoclaved aerated concrete has the following characteristics: density up to 800 kg/m 3, compressive strength class B2.5-B3.5.
• Stability of quality, which is regulated by GOST, adopted in 2007. Products produced at industrial enterprises are accompanied by quality certificates.
• Uniformity of the material. Its difference is that during production the processes of gas formation and hardening occur simultaneously throughout the entire volume of raw materials. Ready-made aerated concrete blocks have pores of the same size and do not have air pockets.
• Eco-friendly, breathable. Buildings made of autoclaved aerated concrete blocks maintain a microclimate similar to the climate wooden log house. In production, mineral raw materials are used that are resistant to mold, mildew, and decay.
• Shrinkage. Aerated concrete blocks are not subject to shrinkage deformations, since they gain sufficient strength during production and autoclave processing.
• Accuracy of geometric dimensions. This indicator is determined by GOST. Deviations should not exceed 2 mm in width, 3 mm in length and 1 mm in thickness. In production aerated concrete building materials resort to cutting large quantities. This allows you to withstand required dimensions blocks with high precision, which ultimately improves the quality of masonry.

Aerated concrete production technology

The technological process includes the following stages:

• Combination of water and sand with particle grinding.
• Introduction of lime, cement and table salt. Mixing of raw materials.
• Pouring the resulting solution into the formwork.
• A hydrogen reaction that releases gas, which creates a porous structure.
• Hardening of the mass within 2-3 hours.
• Cutting into blocks using industrial strings.
• Autoclaving of aerated concrete.

Areas of use

The scope of application of autoclaved aerated concrete is not limited to the construction of industrial buildings. The material is used for the construction of residential buildings.

The blocks are suitable for laying single-layer or double-layer external walls. Partitions for fireproof rooms are made from them.

Other areas of use:

• construction of floor slabs in buildings;
• production wall panels for industrial and residential buildings.

The demand for autoclaved aerated concrete is so high that the manufacturers of this material have united into a national association, which is designed to discuss the prospects for the development of the industry and develop new requirements for quality and innovative approaches to the organization of production.

Aerated blocks obtained by processing in autoclave ovens have gained popularity and taken their rightful place in industrial and residential construction. The material has many advantages over traditional, including natural, building materials. Automation of gas block production technology makes it possible to obtain products with specified controlled characteristics. First of all we're talking about about the high strength of products and their low thermal conductivity, which is especially important against the backdrop of the constant rise in prices of energy resources.

Compound

Aerated concrete gets its amazing properties thanks to: limestone, Portland cement, calcium silicate, aluminum pastes (suspensions), calcium chlorides, water, etc., which are included in its composition in a strictly defined percentage ratio with each other (to form products with specified density characteristics, etc.). The components are calculated in kilograms to obtain 1 m3 ready mixture. The binder can be lime, cement, slag, gypsum, either alone or in various mixtures. The most common base is cement with parts of lime. Additional additives allow the production of blocks different color and impart specific properties to products.

Advantages of the material

Autoclaved aerated concrete has a number of technological, operational and production advantages. The blocks are light in weight, which is convenient when building walls. One unit of the product can replace up to 20 masonry bricks, which speeds up construction. Factory products have high accuracy manufacturing, which reduces the consumption of solutions and ensures the formation of smooth surfaces.

Low ensures heat conservation in buildings without additional thermal insulation. Provides sound insulation and has the required degree of gas permeability (similar to wood). When heated, the material does not emit gases hazardous to health and has high fire resistance. He is also neutral environment for microorganisms. The blocks are easy to drill and saw even with a hand saw.

Material processing is carried out with any tool. Products with a structural and thermal insulation density of the substance (from 500 kg/m3) are intended for the construction of walls of buildings of 3 floors and above. The durability of the products is tens of years. Construction costs are lower than other materials.

Flaws

High-tech material (blocks) has the ability to absorb moisture from the environment and direct precipitation, so it requires additional waterproofing. After installation, the wall structure made of aerated blocks already has lower thermal insulation due to cold bridges, which are created by fastening solutions, reinforced belts, metal mortgages, masonry seams, jumpers, etc. Non-factory produced units do not have standard specifications for this material.

Areas of use

Autoclaved aerated concrete is widely used in construction industrial buildings, residential and commercial real estate. External walls are erected from autoclaved aerated blocks, which can be single-layer, combined or double-layer. Such interior walls designed to take on the load of the upper floors.

It is important to lay the first row perfectly straight.

Autoclave blocks can form partitions and walls of fireproof rooms, as well as fill steel or concrete frames. Separate sphere use - formation of floor slabs (density of autoclaved aerated concrete 800-1000 kg/m3) in buildings. Material with a lower density (slabs) is used for thermal insulation of basements, attics, etc.

Autoclaved aerated concrete has been used in the production of wall panels for residential, public and industrial buildings. This applies to strip-cut reinforced panels. For typical projects large-panel buildings such panels consist of several standard sections.

Production

High-quality autoclaved aerated concrete is produced in conditions industrial enterprises. All processes at production sites are automated, which makes it possible to form aerated concrete products of different formulations with the required characteristics. Production can be easily adjusted to produce products according to customer requests.

Preparing the Components

For the production of autoclaved aerated concrete, it is not quartz sand itself that is used, but a product of its processing, obtained by wet grinding in ball mills. Next, the sand slurry is further processed to the desired consistency in slurry basins. The compacted material is pumped into units that form the required weight proportions of the components.

Dosing and mixing

For this purpose, special automated modules are used, with a capacity of up to 40 cubic meters of products per shift. Enough wide range proportions of mixed starting materials allows you to form autoclaved aerated concrete with specified characteristics. Dosed components of future products according to a given program are mixed with water, aluminum suspension and lime (Portland cement, etc.) in a mixer.

The molds with the mixture are transported to a chamber for maturation and pre-hardening.

The addition of gypsum slows down the thickening process of the mass. After the mixture reaches the density of pouring sour cream, it is poured into molds up to half the level. Regulating the amount and ratio of aluminum and lime determines the volume of hydrogen gas released and, as a result, the different densities of aerated concrete. Impact loads on molds accelerate chemical processes replacing hydrogen in voids with air in aerated concrete, increasing the volume of the material and filling molds with it. Primary ripening and hardening of the material occurs.

Comments:

Autoclaved aerated concrete is a prominent representative of porous concrete and has proven itself quite well in many countries around the world. Such materials have now found wide application in the construction of residential and industrial facilities.

The main components of autoclaved aerated concrete: cement, quartz sand and special gas generators.

Currently, many companies are engaged in the production and sale of the material. Autoclaved aerated concrete on the market building materials presented in a wide range: different shapes, sizes and color. One thing is constant - high performance characteristics, which distinguish it favorably from other products.

Material structure

Aerated concrete is a type of cellular concrete in which air pores measuring 1-3 mm are located throughout the entire volume. Its basis is concrete mixture from a binder, filler and water.

In general, the class of aerated concrete includes (divided by type of binder composition) aerated concrete into cement based, gas silicate with lime as a binder, gas slag concrete based on slag and gas gypsum. Like autoclaved aerated concrete, greatest distribution I found a cement-based material with the addition of lime.

Air pores in the structure are created due to chemical reaction with the release of gas. To initiate this reaction, aluminum powder or paste is added to the mixture. Thus, the composition of aerated concrete, in general, is a mixture of cement, lime, sand, water and aluminum powder residues. If necessary, additives can be added to impart specific properties. Accordingly, the structure of autoclaved concrete is a hardened concrete mass with numerous small pores evenly distributed throughout the volume.

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Manufacturing Features

Autoclaved aerated concrete gets its name from the method of hardening the concrete mass after a chemical reaction with the release of gas. Scheme full cycle production of the material is shown in Fig. 1.

The production of such aerated concrete is carried out in an autoclave in the following order. The concrete mixture is mixed to the consistency of sour cream and poured into molds to half the volume, while a shock load is applied to the mixture, during which the process of slaking lime occurs with the release of heat. Since all this happens in an autoclave, the temperature rises to 80 degrees.

Figure 1. Scheme of the full production cycle of autoclaved aerated concrete.

An active reaction of aluminum and lime begins with the release of hydrogen. The concrete mass increases in volume and fills the entire form. Pressure rises in the autoclave. Under the influence of temperature and pressure, cement hardens, clogging the pores inside its volume. During the reaction, air displaces hydrogen from the pores, filling them. In this way, a concrete structure is formed in which air pores occupy up to 80% of the total volume. By changing the mode and amount of introduced aluminum powder, the pore concentration can be changed over a wide range.

Autoclave hardening of the mass is carried out within 1-2 hours. Then the lid of the autoclave is removed and the aerated concrete is cut into blocks of the required size, while complete hardening of the concrete is not yet achieved. When cutting, the end elements of block engagement are formed (if necessary). After cutting, the blocks are again placed in an autoclave, where they are moistened at a temperature of about 190 degrees and a pressure of up to 1.2 MPa. Under this influence, the mass finally crystallizes to form a durable mineral. Final hardening and crystallization occur within 12 hours. Typically, the concrete mixture is prepared in the following proportion: cement (usually Portland cement) - 20%, quartz sand - 60%, lime - up to 20%. Aluminum residues - no more than 1%.

The main advantage of the autoclave hardening method is that when exposed to high temperature and pressure, cellular aerated concrete forms a special mineral formation - tobermorite, which has an increased mechanical strength and is not subject to shrinkage. In addition, such artificial conditions significantly accelerate the hardening process of the mass, which is very important in industrial production.

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Basic properties of the material

Due to its porous structure, aerated concrete has a low specific gravity (from 300 to 700 kg/m³) and high thermal insulation properties. The autoclave production method also provides high compressive strength, up to 50 kg/cm².

By varying the pore volume, the density of aerated concrete changes; At the same time, strength and thermal conductivity change. At the same time, changes in the main parameters occur in different directions. A decrease in density (increase in porosity) leads to an increase thermal insulation properties and a decrease in strength, and an increase in density has the opposite effect.

Based on this dependence, autoclaved aerated concrete is divided into 3 categories: thermal insulation, structural and structural-thermal insulation. Autoclaved concrete with a density of up to 400 kg/m³ is a thermal insulation type and is intended for private low-rise houses in areas with a fairly cold climate. Aerated concrete with a density of 700 kg/m³ is structural and is used in load-bearing structures and houses with several floors, but it will have to be additionally covered with thermal insulation. Structural and thermal insulating concrete with a density of 500 kg/m³ has optimal properties, which, with sufficiently high strength, provide good thermal insulation.

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What are the block sizes?

The low weight of porous concrete makes it possible to use building elements with increased sizes. Building blocks made of aerated concrete are 625 mm long, 200 and 250 mm high, 100-400 mm wide. Such dimensions make it possible to significantly speed up and simplify the laying of walls, while the weight of the block remains within reasonable limits for its manual movement and laying.

An important advantage of autoclaved concrete is the accuracy and stability of the geometry of building elements (blocks). Autoclave curing of the concrete mass in the mold allows for clearly defined edges and corners, even smooth surfaces of the edges, very high dimensional stability, which remain almost unchanged over a long production time. If you take blocks from different production batches, then deviation is only possible within 1.5 mm in all directions (first category of accuracy) or up to 3 mm for the third category. Very strict standards have also been established for the stability of ribs and corners.

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Other properties of aerated concrete

Autoclaved aerated concrete has high vapor permeability. In terms of its breathability, it belongs to “breathable” building materials, i.e. capable of removing steam from the room to the outside. This property prevents the formation of mold or fungi in areas of steam condensation.

The porous structure provides increased sound insulation properties.

The material will gain wide popularity in Europe due to its environmental friendliness. The composition of aerated concrete does not contain any harmful impurities (even aluminum is found in small quantities and in a bound state), which eliminates harmful emissions both during construction and during operation. The environmental friendliness of the composition is not disturbed even by exposure high temperatures and other climatic factors. In its own way fire safety and fire resistance, aerated concrete can be considered unique. Even prolonged exposure to open flame and thermal stress does not ignite or destroy the material.