Strength of gas silicate blocks. Gas silicate blocks properties and characteristics. Gas silicate blocks delivery and storage

Gas silicate blocks are a kind of wall material made of cellular concrete.

Special pore-forming additives are added to the prepared concrete mix. In the 19th century, bovine blood was mixed in to achieve this effect.

In the early 30s, the Soviet builder Bryushkov drew attention to a plant that grows in Central Asia - the soap root.

The cement mortar, when mixed with the foam of this plant, acquired the ability to foam and increase in volume, and when solidified, it retained the resulting porous structure.

Then, various chemical gas-forming additives began to be added. Unfortunately, we have not patented this method of production. artificial stone. This was done by the Swedish architect Ericsson in 1924.

Composition of gas silicate blocks

Blocks of gas silicate mixtures are a wall material that allows you to create a healthy microclimate in the room, as it has good diffuse characteristics. That is, the building "breathes", which eliminates the appearance of mold. What initial components are taken for the manufacture of blocks?

Aerated concrete mixture, according to SN 277-80 "Instructions for the manufacture of products from cellular concrete" consists of:

• Portland cement, manufactured in accordance with GOST 10178-76, with a calcium silicate content of at least 50%, tricalcium aluminate no more than 6%. Tripoli addition is not allowed.
• Sand must meet the requirements of GOST 8736-77, clay and silt inclusions no more than 2%, quartz content no less than 85%.
• Water with technical requirements according to GOST 23732-79.
• Calcium boiling lime must comply with GOST 9179-77, and be at least grade 3. additional characteristics: quenching speed 5-15 min., "burnout" - no more than 2%, the content of CaO + MgO - at least 70%.
• A blowing agent is used - aluminum powder PAP-1 or PAP-2
• Surface-active substance (surfactant) - sulfonic acid.

Types and characteristics

According to the method of manufacture, gas silicate is divided into:

• non-autoclave - the working mixture hardens in natural conditions. This way you can get cheaper material, but such blocks will have worse strength characteristics, and shrinkage during drying is five times higher than that of an autoclaved product.
• autoclaved - blocks with increased strength and shrinkage upon drying. Autoclave production is energy-intensive and technologically advanced. The steaming of the gas silicate produced is carried out at a pressure of 0.8-1.2 MPa and a temperature of 175-200ºС, which large enterprises can afford. This must be remembered when purchasing blocks of gas silicate.

Calculating the percentage of ingredients in the composition of the aerated concrete mixture, you can get various characteristics gas silicate. For example, by adding Portland cement, we increase strength and frost resistance (by reducing the number of "dangerous pores"), but worsen the thermal conductivity of the product.

The main physical and mechanical properties of blocks:

1. By density, gas silicate blocks are divided into the following types:

• Structural: grades D700 and above. Used for the construction of high-rise buildings - up to three floors.
• Structural and heat-insulating: grades D500, D600, D700. Can be used for partitions and bearing walls low-rise buildings. True, it should be noted that the products of the D500 brand for some manufacturers belong to heat-insulating types.
• Heat-insulating: not higher than D400 grade. This type of gas block is designed for the heat-insulating contour of load-bearing walls built from more durable materials.

It should be mentioned that professional practitioners advise: use the construction of walls with a supporting frame if it is assumed that the future house will have more than two floors. You should probably heed this advice.

2. The thermal conductivity index depends on the purpose of the block:

• Structural grades have thermal conductivity from 0.18 to 0.20 W / m ° C, which is lower than those of clay bricks.
• Structural and heat-insulating - from 0.12 to 0.18 W / m ° С.
• Heat-insulating - from 0.08 to 0.10 W / m ° С. If compared with the thermal conductivity of wood (0.11 to 0.19 W / m ° C), then the gas block will take precedence.

It must be remembered that this figure refers to completely dry material. When wet, this characteristic deteriorates.

3. The frost resistance of gas silicate blocks depends on the characteristics of the cellular structure, which is divided into three classes:

• Reserve - the volume of pores with a diameter of more than 200 microns
• Safe - pore volume with a diameter of less than 0.1 microns
• Dangerous - from 200 to 0.1 microns

If the ratio of the reserve volume to the dangerous volume is more than 0.09, then the aerated concrete block will have high frost resistance. The frost resistance of gas blocks is quite high. It is equal to: 15, 25, 35 cycles. Some manufacturers claim 50, 75 or even 100 cycles. Like, for example, the Saratov plant, which produces YTONG blocks.

But it must be borne in mind that GOST 25485-89 normalized grades for frost resistance starting from D500, and this figure was not higher than F35.

Therefore, it is advisable to be wary of the frost resistance of their products declared by manufacturers. One may ask the meaning of the above relation.

Dimensions and weight

By purpose, gas silicate blocks are distinguished:

• Wall block. Standard size of gas silicate block: 600×200×300mm (length; depth; height)
• Wall block. Its size: 600×100×300 mm.
• The dimensions of gas silicate, depending on the manufacturer, can vary significantly: 500 × 200 × 300 mm; 588×150×288 mm; 588×300×288 mm; 600×250×400 mm; 600×250×250mm etc.

How much does a gas silicate block weigh? Its weight, of course, depends on the density and volumetric characteristics of gas silicate:

• The weight of the structural wall block is 20 kg - 40 kg. Semi-block - from 10 kg to 16 kg.
• The weight of the structural and heat-insulating block is from 17 kg to 30 kg. Semi-block - from 9 kg to 13 kg.
• The weight of the heat-insulating block is from 14 kg to 21 kg. Semi-block - from 5 kg to 10 kg.

Advantages and disadvantages

Advantages of gas silicate blocks:

• Low density (light weight), exerts little pressure on the building foundation. Allows you to reduce construction time, reduce labor and transportation costs.
• Low thermal conductivity. It is three times lower than that of clay bricks.
• High sound insulation. It is 10 times higher than brickwork.
• Almost perfect geometry of products, which allows laying on special adhesives.
• Relatively low cost.
• Excellent refractory properties.
• They create a healthy indoor climate.

Disadvantages of gas silicate blocks:

1. The construction of a house from this wall material requires highly qualified workers with experience in working with gas silicate:

• If we do not want to get a wall in cracks, a high-quality foundation is necessary. It is important that at the base (or plinth), the horizontal deviations are no more than 3 mm for a length of 2 m.
• Laying on adhesives must be carried out with particular care: a gap in the adhesive joint is unacceptable, otherwise we will get natural ventilation through the walls, and, contrary to expectations, the house will be cold. Do not make seams less than 3-5 mm thick.
• Expensive interior decoration. Plaster without fail on a grid (fiberglass), so that cracks would not appear. The plaster layer should be no more than 4-5 mm.

2. The need to finish the facade, not only because of the unsightliness of the masonry, but also because the gas silicate absorbs moisture well. In connection with this feature, it is not recommended to use it in areas where the humidity is more than 60%.

3. Aerated concrete wall does not hold heavy hanging objects well.

How much does a gas block cost?

Depending on the manufacturer and brand, the price for 1 m3 (28 pieces - 600x200x300) is:

• Wall, structural and heat-insulating block from 3500 rubles. up to 3800 rub.
• Structural - about 3800-4000 rubles.

The price for 1 piece of a gas silicate block of a standard size, for structural and thermal insulation purposes, ranges from 120 to 140 rubles.

Gas silicate blocks are a building material of universal value. It is an artificial porous stone. This structure is formed by a natural chemical reaction between aluminum and lime. During the reaction, these two components decompose and form hydrogen.

In the context of a constant rise in the price of energy carriers, the need for building materials with high thermal performance increases. To reduce heat loss in modern projects more and more often, aerated concrete and gas silicate blocks are used - materials of the class of heat-insulating cellular concrete. They are often confused due to common properties and the same scope. Even specialists cannot always immediately tell a potential customer which material is in front of him - gas silicate or aerated concrete, which is better, what is the difference between them and whether there is one at all. In part, the manufacturers themselves are confusing when they define aerated concrete as a type of gas silicate or vice versa.

What is the difference between aerated concrete and gas silicate? In particular, in the manufacture of aerated concrete, natural hardening of the block in the open air is allowed, for gas silicate - autoclave ovens are prerequisite. In addition, for aerated concrete blocks, the main binding component is cement, for silicate analogues, lime. The use of different components affects the color of the finished blocks.

If we talk about specific characteristics, you can notice the following differences:

• Gas silicate blocks have a uniform distribution of hollow cells, which ensures high strength.
• The weight of aerated concrete blocks is much greater, which requires a reinforced foundation during construction.
• In terms of thermal insulation, gas silicate blocks outperform aerated concrete ones.
• Aerated concrete absorbs moisture better, which provides more freezing cycles.
• Gas silicate blocks have a more consistent geometry, as a result, it is possible to simplify finishing wall structures.

Externally, finished products are distinguished by color: gas silicate or autoclaved aerated concrete almost white, grey colour characteristic of non-autoclaved aerated concrete.

The average values ​​for each parameter are shown in the following table:

In terms of durability, the materials are identical and can last more than 50 years.

If you answer the question: “Which is better, aerated concrete or gas silicate?”, Gas silicate blocks have much more technical advantages. However, manufacturing technology forces to increase the cost of finished products, therefore aerated concrete blocks cost less. Therefore, those who wish to build a house of high quality and modern material choose gas silicate, who want to save on construction - they prefer aerated concrete.

At the same time, the region of application must be taken into account: in areas with high air humidity, the service life of gas silicate blocks is noticeably reduced.

Composition and production technology of gas silicate blocks

The mixture for the production of gas silicate blocks has the following composition:

• binder (Portland cement according to GOST 10178-76, calcium boiled lime (according to GOST 9179-77);
• silicate or siliceous filler (quartz sand with 85% quartz content, fly ash, etc.);
• lime, with a content of magnesium and calcium oxides of more than 70%, and a quenching speed of up to 15 minutes;
• technical water;
• gas-forming additive (aluminum powder and others).

Gas silicate belongs to the class of lightweight cellular concrete. This material is a mixture consisting of 3 main components: cement, water and fillers. Lime and quartz sand in the ratio of 0.62:0.24 can act as fillers. Separately, it is worth talking about additives, which give the gas silicate its individual characteristics. Fine aluminum powder acts as an additive. All these components are thoroughly mixed, and under certain observed conditions, foaming of all these materials occurs. When aluminum powder reacts with lime, hydrogen is released. A huge amount of hydrogen bubbles released makes up the porous structure, which is the main distinguishing feature of gas silicate. In its structure, it resembles a concrete "sponge", since the entire volume of the block consists of cells (bubbles with a diameter of 1-3 mm).

gas silicate blocks

The cellular structure makes up almost 85% of the volume of the entire block, so this material is very light in weight. First, a mixture of components is prepared in a special mixer for 5 minutes, which includes Portland cement, fine sand (quartz), water, lime and a blowing agent (most often, it is a suspension of aluminum). Hydrogen formed by the reaction between aluminum paste (powder) and lime forms pores. Bubbles ranging in size from 0.6 to 3 mm are evenly dispersed throughout the material.

In metal containers or molds, the main chemical reactions take place. The mixture is subjected to vibration, which promotes swelling and setting. After hardening, all irregularities from the surface are removed with a steel string. The formation is divided into blocks, and then they are sent to the autoclave unit. The final calibration of the finished blocks is carried out by a milling machine.

Gas silicate blocks are made only by autoclave. Aerated concrete blocks can be made both by autoclave and non-autoclave method (natural hardening of the mixture):

1. Autoclave processing. This stage significantly improves the technical characteristics of gas silicate. Here for 12 hours high pressure steam treatment is carried out, the temperature of which is almost 200 ° C. This heating process makes the texture more uniform, thereby improving the strength properties (not less than 28 kgf/m²). Its specific thermal conductivity is 0.09-0.18 W (m∙K), which allows you to build walls in one row (400 cm) in almost any climatic conditions but excluding the northern regions.
2. Non-autoclave technology. It consists in the natural hardening of the mixture: moisturizing and drying in natural conditions. In this case, it is quite possible to make it yourself, since no special equipment is required here. The strength of blocks in such production does not exceed 12 kgf / m².

The first variety is more expensive. This is due to significant manufacturing costs, as well as the best technical characteristics of gas silicate blocks produced by this method. They are much stronger, their coefficient of thermal conductivity is less. The pores inside such a gas silicate are distributed extremely evenly, which affects the strict compliance of the material with the specified parameters.

Gas silicate blocks: characteristics

Density of gas silicate blocks

The brand and density of gas silicate blocks is indicated in the marking and determines the purpose of the block:

• structural gas silicate blocks - D1000-1200, have a density of 1000 to 1200 kg / m3;
• structural and heat-insulating blocks - D500-900, have a density of 500-900 kg / m3;
• heat-insulating D300-D500, the density of their materials is 300-500 kg / m.

Blocks of different density are easy to distinguish from each other visually.

There are several classifications of gas silicate blocks with certain technical characteristics. Today, during construction work, the following grades of this material are used. The best option for low-rise construction - gas silicate block d500 and gas silicate block d600.

The digital designation of the brands listed earlier shows the density of the material. In particular, the d500 gas silicate block has a density of 500 kg/m³.

Gas silicate block d600

The gas silicate block d600 is used in the construction of load-bearing walls of the house. It is also recommended for use in the construction of ventilated facades, which are well attached to blocks of this density. The gas silicate block d600 has a strength of 2.5-4.5 MPa and has a thermal conductivity index of 0.14-0.15 W / (m ° C)

Gas silicate block d500

The d500 gas silicate block is most popular for low-rise (up to 3 floors) construction. This variety is also used in monolithic construction. Its parameters are 2-3 MPa (strength) and 0.12-0.13 W / (m ° C) (thermal conductivity).

When building a house above three floors, gas silicate with a marking above D600 should be preferred and the walls should be additionally insulated. Based on the value of the thermal conductivity coefficient, it can be concluded that the d500 gas silicate block is warmer than the d600 gas silicate block by 15-17%.

Gas silicate block d400

This variety is used for arranging insulation, for working with openings during the construction of multi-storey buildings using a monolithic method. The D400 brand is also popular in private construction. With high strength, it has great heat-insulating properties. These indicators are in the range of 1 MPa to 1.5 MPa (strength), 0.10-0.11 W / (m ° C) (thermal conductivity).

Gas silicate block d300

Brand D350 can only be used as a heater. In the domestic market, this is a rather rare brand, due to its fragility. Strength is in the range of 0.7-1.0 MPa. But it differs in thermal conductivity, which is 0.08-0.09 W / (m ° C).

Thermal conductivity of gas silicate blocks

Depending on the proportions of the initial ingredients, a product with different performance characteristics can be obtained. The thermal conductivity coefficient of the gas silicate block depends on its density and is determined by marking: D300, D400, D500, D600, D700.

The thermal conductivity of gas silicate depends on a number of factors:

1. Building block dimensions. The greater the thickness of the wall block, the higher its heat-insulating properties.
2. Humidity of the environment. Material that absorbs moisture reduces the ability to store heat.
3. Structure and number of pores. Blocks that have a large number of large air cells in their structure have increased heat-insulating performance.
4. Density of concrete partitions. High-density building materials retain heat worse.

Table of thermal conductivity of gas silicate blocks

Types of gas silicate blocks

By appearance There are several configurations of the gas silicate block. The classification is based on the purpose of the block.

• Smooth (straight) gas silicate block with grip for hands

Absolutely smooth rectangular gas silicate block with recesses for gripping hands. The grip is comfortable to use, as it allows you to easily move the blocks. The presence of grip handles increases the consumption of glue, since the technology of laying gas silicate blocks provides for filling all voids during operation.

• Wall gas silicate blocks with flat edges

The usual rectangular shape reduces the consumption of glue, but makes it difficult to move the block. In practice, in the construction of load-bearing walls, where larger blocks are used, a block with a grip is preferred.

• Gas silicate blocks for partitions

They are blocks with flat edges. Partition blocks are thinner and lighter in weight. It is convenient to work with them.

On straight blocks, you can cut any pattern with a screwdriver. But such a decor is more applicable in finishing the site with the remains of blocks from the construction than in the construction itself, since it is desirable to protect the gas silicate with an external finishing material.

• Wall gas silicate blocks tongue-and-groove

The formation of the tongue-and-groove connection system, according to the complexity of production, refers to the high-tech processing of the block. Therefore, they are more expensive. However, it is justified because: it increases the speed of work, reduces the consumption of glue (vertical joints do not need to be glued), it becomes possible to eliminate cold bridges in places of vertical joints.

If the house will not be exposed to exterior decoration. At the junction, it is better to apply a thin layer of glue from the front side of the masonry. This will provide additional seam insulation.

• U-shaped gas silicate blocks

The purpose of the U-shaped blocks is the installation of hidden building elements (for lintels and monolithic belts). According to technology, the laying of walls from gas silicate blocks provides for mandatory reinforcement, the first and every fourth of the subsequent rows. It is in order to conveniently hide the reinforcement that the voids in the U-shaped blocks are designed. After laying the reinforcing metal, the space must be filled concrete mortar or glue. In this case, a cheaper filling material should be used.

What are the sizes of gas silicate blocks

Of course, manufacturers produce gas silicate blocks of various sizes. However, most enterprises try to follow the established standards of GOST No. 31360 of 2007. Here are the dimensions of the finished products:

• 250*250*600.
• 250*400*600.
• 500*200*300.
• 600*100*300.
• 600*200*300.

It is important to understand that, according to GOST, deviations in the length and diagonal values ​​\u200b\u200bare allowed, which refer finished products to the 1st or 2nd category.

Deviations in the size of the gas silicate blocks reduce installation time due to the absence of the need for grinding and fitting.

• Thickness of gas silicate blocks: 200, 250, 300, 350, 375, 400, 500 mm;
• The thickness of partition blocks is 100-150 mm;
• Length of gas silicate blocks: 600, 625 mm;
• Height of gas silicate blocks: 200, 250, 300 mm;
• Weight of gas silicate blocks: 14-34 kg;
• In 1 cubic meter from 13 to 33 pcs. (depending on thickness);
• Consumption per 1 sq.m. walls is 6.7-7 pieces.

The exact parameters are shown in the tables below:

Dimensions of the U-shaped gas block The size of the gas silicate block for walls (LxWxH) from different manufacturers and the number of pieces on the pallet.

Number of blocks in a pallet

Weight of gas silicate block

The structural mass of the block varies depending on the density of the finished product. Judging by the markings, we can distinguish the following weight:

• D400. Weight 5-21 kg.
• D500/D600. Weight - 9-30 kg.
• D700. Weight - 10-40 kg.

In addition to density, the overall size of the finished block is considered to be a fundamental factor in the change in weight.

Pros and cons of gas silicate blocks

Like any building material, gas silicate blocks have strengths and weaknesses. The positive characteristics include the following points:

1. Aerated concrete belongs to the category of non-combustible materials and is able to withstand exposure to an open flame for up to 5 hours, without changing its shape and properties.
2. Large dimensions provide fast erection of wall structures.
3. The blocks have a specific low weight, which greatly simplifies the workflow.
4. Only natural materials are used in the production, so gas silicate blocks are environmentally friendly.
5. The porous structure provides high values ​​of thermal insulation of the premises.
6. The material is easy to process, which helps to build walls with complex geometry.

The disadvantages include the following:

1. They absorb moisture well, which reduces the service life.
2. Application for adhesion of special adhesive compositions.
3. Mandatory exterior finish.

It should be noted that a solid foundation is required for gas silicate blocks. In most cases, a reinforcing belt is required.

IN construction industry gas silicate products are used. The block production process is carried out under high pressure, as well as in natural conditions. Due to the porous structure, they retain heat well. The D500 gas silicate block is popular, the characteristics of which make it possible to use this material in the construction of houses. As a result of the use of blocks of increased size, the building construction cycle is reduced. Consider the main technical characteristics that must be considered when choosing a material.

What are gas silicate blocks

Gas silicate block products are a modern building material made from the following raw materials:

• Portland cement, which is a binder ingredient;
• quartz sand introduced into the composition as a filler;
• lime involved in the gas formation reaction;
• powdered aluminum added to foam the mass.

When mixing the components, the working mixture increases in volume as a result of an actively occurring chemical reaction.

Gas silicate blocks are widely used in the construction industry

Molding containers filled with silicate mixture solidify under various conditions:

• naturally at ambient temperature. The curing process lasts 15-30 days. The resulting products are characterized by a reduced cost, but have insufficiently high strength;
• in autoclaves, where products are heated at elevated pressure. Steaming allows you to increase the strength characteristics and specific gravity gas silicate products.

The density and strength indicators change depending on the manufacturing method. The indicated characteristics of the materials determine the area of ​​use.

Blocks are divided into the following types:

• structural products. They are marked D700 and are in demand for the construction of main walls, the height of which is no more than three floors;
• thermal insulation products. Brand D500 corresponds to these blocks. They are used for the construction of internal partitions and the construction of load-bearing walls of small buildings;
• thermal insulation products. They are characterized by increased porosity and density reduced to D400. This allows the use of gas silicate material for reliable thermal insulation of walls.

The digital index in the marking of the blocks corresponds to the mass of one cubic meter of gas silicate, indicated in kilograms. As the density of the material increases, its thermal insulation properties decrease. Products of the D700 brand are gradually replacing traditional bricks, and products with a density of D400 are not inferior in terms of thermal insulation properties to modern heaters.

Gas silicate blocks are superior in mechanical strength to foam concrete

Gas silicate blocks - the pros and cons of the material

Gas silicate products have a complex of serious advantages. The main advantages of gas silicate blocks:

• reduced weight with increased volume. The density of gas silicate material is 3 times less compared to brick and about 5 times lower when compared to concrete;
• increased margin of safety, allowing to perceive compressive loads. The strength index for a gas silicate block marked D500 is 0.04 t / cm³;
• improved thermal insulation properties. The material successfully competes with annealed brick, the thermal conductivity of which is three times higher than that of gas silicate;
• correct block shape. Due to the reduced tolerances for overall dimensions and clear geometry, the laying of blocks is carried out on a thin layer of adhesive mortar;
• increased dimensions. The use of large-sized silicate blocks with low weight for the construction of walls of buildings reduces the duration of construction;
• good machinability. If necessary, it is easy to give the gas silicate block a predetermined shape or cut the block material into separate blanks;
• acceptable price. Using block gas silicate for the construction of a cottage, a private house or a summer residence, it is easy to significantly reduce the estimated cost of construction activities;
• fire safety. Blocks do not ignite when heated and exposed to open flame. They belong to low-combustible building materials included in the combustibility group G1;
• high soundproof properties. They are provided due to the porous structure. In terms of ability to absorb external noise, the blocks are ten times superior to ceramic bricks;
• environmental friendliness. In the manufacture of a gas silicate mixture, toxic ingredients are not used and no components harmful to health are released during operation;
• vapor permeability. Air exchange occurs through the air cells inside the gas silicate massif, creating a favorable microclimate inside the building;
• frost resistance. Gas silicate blocks retain the structure of the array and operational characteristics, withstanding more than two hundred cycles of prolonged freezing followed by thawing;
• heat storage properties. Gas silicate blocks are an energy-saving material that is able to accumulate thermal energy and gradually release it to increase the room temperature.

The area of ​​application depends on the density of the material

Despite many advantages, gas silicate blocks have weaknesses. The main disadvantages of the material:

• increased hygroscopicity. Porous gas silicate blocks gradually absorb moisture through an unprotected surface, which destroys the structure and reduces strength;
• the need to use special fasteners for fixing hanging furniture and equipment. Standard fasteners do not provide reliable fixation due to the cellular structure of the blocks;
• insufficient mechanical strength. Block material crumbles under load, therefore, it requires careful handling during transportation and laying;
• mold formation and the development of fungal colonies inside and on the surface of the blocks. Due to the increased moisture absorption, favorable conditions are created for the growth of microorganisms;
• increased shrinkage. Under real operating conditions, under the influence of loads, the blocks gradually shrink, which causes the formation of cracks after a while;
• reduced adhesion with sand-cement plasters. It is necessary to use special finishing compounds for plastering gas silicate.

Despite the existing shortcomings, gas silicate blocks are actively used for the construction of capital walls in the field of low-rise construction, as well as for the construction of heat-insulated walls of multi-storey buildings and for thermal insulation of various structures. Professional builders and private developers prefer gas silicate blocks due to the significant advantages of the material.

Gas silicate block D500 - building material characteristics

Structural and heat-insulating block D500 is used for various purposes:

• construction of boxes of low-rise buildings;
• arrangement of interior partitions;
• reinforcement of door and window openings.

Gas silicate blocks provide good thermal insulation premises

Having decided to purchase block silicate marked D500, you should familiarize yourself in detail with the performance properties of a popular building material. Let's dwell on the main characteristics.

Strength properties

The compressive strength class of the material varies depending on the block manufacturing method:

• gas silicate grade D500, obtained by the autoclave method, is characterized by a strength index of B2.5-B3;
• the compressive strength class for similar non-autoclaved blocks is B1.5.

The strength of D500 blocks reaches 4 MPa, which is not high enough. To prevent cracking of the gas silicate material, the masonry is reinforced with mesh or reinforcement. A relatively low margin of safety allows the use of block building material in the field of low-rise construction. During the construction of multi-storey buildings, gas silicate blocks are used in conjunction with bricks for thermal insulation of the walls being erected.

Specific gravity

The density of gas silicate blocks is an important performance indicator that characterizes the porosity of a block massif. Density is indicated by marking in the form of the Latin letter D and a digital index. The number in the marking characterizes the mass of one cubic meter of gas silicate. Yes, one cubic meter gas silicate marked D500 weighs 500 kg. Knowing the marking of products by density, the dimensions of the blocks and their number, it is easy to calculate the load on the foundation.

Gas silicate blocks - environmentally friendly material

Thermal performance

The thermal conductivity of gas silicate blocks is the ability to transfer thermal energy. The value of the indicator characterizes the thermal conductivity of gas silicate blocks.

The value of the coefficient varies depending on the moisture concentration in the material:

• thermal conductivity coefficient of dry gas silicate material grade D500 is 0.12 W/m⁰С;
• with an increase in humidity to 5%, the thermal conductivity of the D500 blocks increases to 0.47 W / m⁰С.

In buildings built from gas silicate blocks, due to the reduced thermal conductivity of the material, a favorable microclimate is maintained year-round.

Frost resistance

The ability of gas silicate blocks to perceive temperature changes associated with deep freezing and thawing is characterized by marking. The frost resistance index for D500 products is F50. Compared to other types composite concrete this is a pretty good indicator. Frost resistance is affected by the moisture concentration in the blocks. With a decrease in the moisture content of the material, the frost resistance of the blocks increases.

Lifetime

Gas silicate has a long period of use. The structure of the gas silicate massif has been intact for more than half a century. Block manufacturers guarantee the service life of products for 60-80 years, provided that the blocks are protected from moisture absorption. Plastering the material allows you to extend the service life.

Fire safety

Gas silicate blocks are a fireproof building material with fire resistance up to 400 ⁰С. Tests confirm that a gas silicate wall covered with plaster is able to withstand exposure to open fire for three to four hours. The blocks are suitable for the construction of fire-resistant walls, partitions and chimneys.

Conclusion

Block gas silicate is a proven material for the construction of low-rise buildings. The characteristics of the blocks make it possible to ensure the stability of the buildings under construction and maintain a comfortable microclimate inside the buildings.

Blocks of gas silicate are in great demand in residential and industrial construction. This building material surpasses concrete, brick, natural wood, etc. in many respects. It is made from environmentally friendly raw materials, is lightweight, fireproof, easy to operate and transport. The use of this lightweight material reduces the cost of arranging a heavy reinforced foundation and thereby reduces the cost of building a building.

What are gas silicate blocks

The gas silicate block is a lightweight and durable wall material, which is made of cellular concrete. Products have a porous internal structure, which has a positive effect on their heat and noise insulation properties. Such building material can be used in various areas of the construction industry - for the construction of summer cottages and country houses, car garages, utility buildings, warehouse complexes, etc.

How are gas silicate blocks made?

There are two main technologies for the production of gas silicate building blocks.

• non-autoclave. With this method of production, the solidification of the working mixture occurs in natural conditions. Non-autoclaved gas silicate blocks are distinguished by a lower cost, but have some important differences from autoclaved ones. First, they are less durable. Secondly, when they dry, shrinkage occurs almost 5 times more intensively than in the case of autoclaved products.
• Autoclave. For the autoclave production of gas silicate, more energy and material resources are required, which increases the final cost of products. Production is carried out at a certain pressure (0.8-1.2 MPa) and temperature (up to 200 degrees Celsius). Finished products are more durable and resistant to shrinkage.

Block types

Depending on the density, composition and functional purpose blocks of gas silicate are divided into three main categories.

• Structural. They have high strength properties. The density of products is not less than 700 kg/m 3 . They are used in the construction of high-rise structures (up to three floors). Able to withstand high mechanical loads. The thermal conductivity is 0.18-0.2 W/(m·°C).
• Structural and heat-insulating. Blocks with a density of 500-700 kg / m 3 are used in the arrangement of load-bearing walls in low-rise buildings. They are distinguished by a balanced ratio of strength and heat-insulating characteristics [(0.12-0.18 W / (m ° C)].
• Thermal insulation. They are distinguished by increased heat-insulating properties [(0.08-0.1 W / (m ° C)]. Due to their low density (less than 400 kg / m 3), they are not suitable for creating load-bearing walls, therefore they are used exclusively for insulation.

Dimensions and weight

Wall blocks made of gas silicate have standard sizes 600 x 200 x 300 mm. The overall characteristics of the semi-blocks are 600 x 100 x 300 mm. Depending on the manufacturer, the product sizes may vary slightly: 500 x 200 x 300, 588 x 300 x 288 mm, etc.

The mass of one block depends on its density:

• structural blocks weigh 20-40 kg, semi-blocks - 10-16 kg;
• structural and heat-insulating blocks and semi-blocks - 17-30 kg and 9-13 kg, respectively;
• heat-insulating blocks weigh 14-21 kg, semi-blocks - 5-10 kg.

Composition of gas silicate blocks

Gas silicate is an environmentally friendly building material, which is made from non-toxic raw materials of natural origin. The composition of the blocks includes cement, sand, lime and water. Aluminum chips are used as a foaming agent, which helps to increase the voidness coefficient of the blocks. Also, in the production of the material, a surfactant is used - sulfonol C.

Material characteristics

Building blocks from gas silicate have the following characteristics.

• Heat capacity. Products made using autoclave technology have a thermal conductivity coefficient of 1 kJ/(kg °C).
• Thermal conductivity. Structural and heat-insulating gas silicate has an average thermal conductivity of about 0.14 W / (m ° C), while for reinforced concrete this parameter reaches 2.04.
• Sound absorption. Gas silicate blocks significantly reduce the amplitude of external noise, the sound absorption index for this material is 0.2.
• Frost resistance. Material with a density of 600 kg/m 3 withstands up to 35 freeze and thaw cycles (which corresponds to the F35 index). Products with more high density Frost resistance class F50 assigned.

Advantages and disadvantages of gas silicate blocks

The main advantages of gas silicate are the following.

• Ease. Blocks of gas silicate weigh almost 5 times less than concrete products of the same size. It makes it easier construction works and reduces the cost of transporting building materials.
• Effective heat and sound insulation. Due to the presence of internal micropores, high heat and noise insulation characteristics of gas silicate are achieved. This allows you to create a comfortable microclimate inside the premises.
• Environmental friendliness. The composition of the building material does not contain dangerous toxins and carcinogens that can harm the environment and human health.
• fire resistance. Gas silicate is made from non-combustible raw materials, therefore it does not collapse during intense heating and does not contribute to the spread of flame in case of fire.

How critical are the shortcomings?

Like any other building material, gas silicate has some disadvantages.

• Low margin of safety. Material with low density (300-400 kg/m3) has relatively low strength characteristics. Therefore, during construction, it is imperative to carry out work on the reinforcement of the walls.
• Smooth surfaces. The front parts of gas silicate blocks have a smooth surface with a low roughness coefficient. As a result, adhesion deteriorates. finishing materials, which complicates the process of finishing walls with plaster and other coatings.
• Low moisture resistance. Due to the increased porosity, the material is sensitive to high humidity. Water and water vapor penetrate the internal micropores and, when frozen, increase in volume, destroying the blocks from the inside. Therefore, walls made of gas silicate need additional waterproofing.

Where are gas silicate blocks used

Gas silicate blocks are used in residential and industrial construction. This material is used not only for the construction of load-bearing elements of buildings, but also to increase thermal insulation, as well as to protect engineering networks(in particular, heating).

The scope of gas silicate is determined by its characteristics, primarily by density.

• Products whose density is 300-400 kg / m 3 have a low margin of safety, so they are used mainly for wall insulation.
• Gas silicate with a density of 400 kg / m 3 is suitable for construction one-story houses, garages, office and outbuildings. Due to the higher strength, the material is able to withstand significant loads.
• Blocks with a density of 500 kg / m 3 are optimal in terms of strength and thermal insulation properties. They are often used to build cottages, country houses and other buildings up to 3 floors high.

The most durable are gas silicate blocks with a density of 700 kg/m 3 . They are used for the construction of high-rise residential and industrial facilities. But due to the increased density, the porosity coefficient of the material decreases and, consequently, its thermal insulation properties. Therefore, walls built from such blocks require additional insulation.

The process of building and testing blocks.

The massive use of gas silicate blocks in construction indicates their great popularity. In terms of value for money, with the remarkable characteristics of aerated concrete blocks, nothing more optimal than gas silicate has yet been invented. Aerated concrete is aerated concrete autoclave- a time-tested building material used in almost all types structural elements structures and buildings for various purposes. But where did the technology for the production of cellular concrete come from, and when did it begin to be used in its modern form? Developments aimed at obtaining a new multifunctional building material have been carried out since the end of the 19th century. By the beginning of the 20th, several foreign experimental scientists managed to obtain a patent for the invention of the so-called “miracle concrete”, because at that time the world was in dire need of large quantities of artificially produced stone for construction. Experimenting with the constituent elements, by trial and error, a prototype of a modern aerated concrete solution was obtained. However, the properties and characteristics of gas silicate blocks were not the same as we know them now, of course, at that time. Modern gas blocks appeared only in the 90s. These are well-known foam concrete, polystyrene concrete and aerated concrete blocks. Regarding the latter, they are of 2 types: non-autoclave and, accordingly, autoclave method of hardening. Non-autoclaved aerated concrete is heterogeneous and quite often contains harmful air pores, which shrink during the operation process. Aerated concrete obtained as a result of using the autoclave method is much more environmentally friendly and stronger than non-autoclaved one (about two times). The method for the production of cellular concrete was proposed in the thirties and since then, in principle, has not changed much, although the properties of gas silicate blocks have constantly improved and the scope of its application has expanded. For its manufacture, sand, cement, lime, gypsum stone and ordinary water are used. A small amount of aluminum powder is also added to the mixture of these materials, which contributes to the formation of small air cells in the mixture, which make the material porous. Immediately after swelling, a short exposure and cutting the array into products of the required dimensions, the cellular concrete mass is placed in an autoclave, where it hardens in a steam environment. This energy-saving technology does not leave any waste that would pollute the air, soil and water. Autoclaved gas silicate blocks are a material with unique properties. After all, it combines the best qualities of two ancient building materials: wood and stone. IN last years in connection with a noticeable increase in the requirements for the thermal insulation qualities of enclosing structures in residential and public buildings, one of the few varieties of concrete, from which it is possible to erect truly heat-efficient structures of optimal thickness, is precisely cellular concrete. The characteristics and properties of gas silicate blocks give this building material a number of very important advantages:

Light weight gas silicate blocks.

Here, perhaps, the main and indisputable advantage of gas silicate over brick. The weight of the gas silicate block is in the range of 488 - 500 hundred kilograms / m3, depending on the size of the aerated concrete blocks.

A conventional block (according to GOST 21520-89) has a density grade of D500 and a size of 250 by 625 with a thickness of 400 mm and a mass of about 30.5 kilograms and, in terms of thermal conductivity, can replace a 64 cm thick wall of twenty-eight bricks, whose weight is one hundred and twenty kilograms. Big sizes gas silicate blocks with low weight significantly reduce installation costs and significantly reduce construction time. To carry out the lifting of aerated concrete, a crane is not needed: several people can handle this, or you can use an ordinary winch, therefore, the light weight of such cellular concrete allows you to reduce not only transport and installation work, but also the cost of arranging foundations. Aerated concrete blocks are much easier to process than foam concrete. They can be sawn, drilled, planed and milled with conventional tools.

Blocks gas silicate environmental friendliness.

Since autoclaved aerated concrete is obtained from sand, cement, lime and aluminum powder, it is not toxic substances are released, as a result, in its environmental friendliness, it is close to wood, but it is not prone to decay and aging. Aerated concrete products are completely safe for humans; in a house built from it, one breathes just as easily as in a house built from wood.

Fast and economical when working with gas silicate blocks.

Thanks to such a characteristic of gas silicate blocks as their impressive dimensions (600 by (50-500) by 250 mm), with low weight, the construction process proceeds quickly and easily. At the same time, the speed of construction increases really significantly (4 times) and, accordingly, labor costs decrease. At the ends of some types of gas silicate block, special grooves and ridges are formed, as well as gripping pockets designed for hands. You absolutely do not need 1-1.5 cm of mortar in the masonry, an adhesive layer of 3-5 millimeters applied with a notched trowel is enough to securely strengthen the block. Aerated concrete blocks have an almost ideal configuration (since the permissible deviation of their faces does not exceed one millimeter), which makes it possible to use the technology of thin-seam masonry and significantly reduces the cost of work. The cost of gas silicate blocks is low compared to the same brick, but the glue for making thin seams is about twice as expensive as the price of sand-cement mortar, but the material consumption in the production of laying an aerated concrete block is reduced by about six times. Ultimately, the resulting thin-joint masonry makes it possible to reduce the cost of masonry mortar by a factor of three, in addition, due to the minimum thickness of the connecting adhesive, cold bridges in the walls are reduced and the house is warmer.

Gas silicate blocks low thermal conductivity.

It is provided by air bubbles, which occupy about 80 percent of the material. Indeed, it is thanks to them that positive qualities aerated concrete blocks have a high thermal insulation capacity, due to which heating costs are reduced by 20-30 percent and you can refuse to use additional heat-insulating materials. The walls, which are made of gas silicate blocks, fully meet the new SNiP requirements for the thermal conductivity of the walls of public and residential buildings. In a dry state, the thermal conductivity coefficient of aerated concrete is 0.12 W / m ° C, at 12% humidity - 0.145 W / m ° C. IN middle lane In Russia, it is possible to build walls from gas silicate blocks (with a density of not more than 500 kilograms / m3), whose thickness is 40 cm.

Energy saving thanks to gas silicate blocks.

Today, energy saving has become one of the most important indicators. It happens that the neglect of this parameter leads to the impossibility of operating a solid brick house: the owner simply could not afford to financially heat such a large room. When using an aerated concrete block with a weight of 500 kilograms / m3, a thickness of 40 cm, the energy-saving parameters are achieved within the normal range. The use of aerated concrete blocks with a density of more than 500 kg / m3 leads to a noticeable deterioration in the parameters (thermal properties are reduced by fifty percent when using blocks with a density of 600-700 kg / m3). Gas silicate blocks with a density of less than 400 kilograms / m3 can only be used in construction as a heater, due to their low strength characteristics.

Blocks gas silicate frost resistance.

The qualities of aerated concrete blocks in terms of frost resistance allow them to become champions among the materials used in low-rise construction. Excellent frost resistance is explained by the presence of reserve voids into which water is displaced during freezing, while the gas silicate block itself is not destroyed. If the technology of building from aerated concrete is strictly observed, the frost resistance of building materials exceeds two hundred cycles.

Soundproofing qualities of aerated concrete blocks.

Due to its cellular finely porous structure, the soundproofing qualities of gas silicate are many times higher than that of brickwork. If there is an air gap between the layers of aerated concrete blocks, or when finishing the wall surface with denser building materials, sound insulation of about 50 dB is provided.

Blocks of autoclave hardening fire safety.

Cellular aerated concrete blocks are not afraid of fire. Chimneys from gas silicate blocks are laid through any wooden structures without cutting, because they conduct heat poorly. And since only mineral raw materials of natural origin are used to produce aerated concrete, aerated concrete blocks belong to the group of materials that do not support combustion and are able to withstand one-sided fire exposure for 3–7 hours. When using aerated concrete blocks in conjunction with metal structures, or as cladding, they are ideal for the construction of fire-resistant walls, elevator and ventilation shafts.

Blocks aerated concrete strength.

With a low volumetric weight of the gas silicate block - 500 kilograms / m3 - it has a rather high compressive strength - in the region of 28–40 kgf / cm3 due to autoclave treatment (for comparison, the same foam concrete is only 15 kgf / cm3). In practice, the strength of the block is such that it can be safely used in the construction of houses with load-bearing walls up to 3 floors, or without limiting the number of storeys - in frame-monolithic construction.

Gas silicate blocks ease and rationality of processing.

Blocks of aerated concrete lend themselves quite easily to any machining: without problems, they can be sawn, drilled, planed, milled, while using standard tools that are used for wood processing. Channels for pipes and cables can be laid using a conventional hand tool, and you can use a power tool to speed up the process. Hand saw will make it easy to give the gas silicate any configuration, which completely solves the issues with additional blocks, as well as the external architectural expressiveness of structures. Channels and openings for arranging electrical wiring, sockets, pipelines, etc. can be cut using an electric drill.

Blocks are gas silicate sizes.

The autoclave block manufacturing process guarantees highly accurate dimensions - typically 250 by 625 millimeters at different thickness in 50 - 500 millimeters (+ - millimeter). Deviations, as you can see, are so minimal that a freshly laid wall is a surface that is absolutely ready for applying putty, which is the basis for wallpaper or painting.

Non-hygroscopicity of aerated concrete block.

Although the autoclaved aerated concrete block is a highly porous material (its porosity can reach up to 90 percent), the material is not hygroscopic. Having fallen, for example, under the rain, aerated concrete, unlike the same wood, dries out rather quickly and does not warp at all. Compared to brick, aerated concrete does not “suck up” water at all, since its capillaries are interrupted by special spherical pores.

Aerated concrete blocks application.

The lightest in weight gas silicate blocks, having a density of 350 kilograms / m³, are used as a heater. Aerated concrete blocks with a density of four hundred kg / m³ are used for the construction of load-bearing walls and partitions in low-rise housing construction. Having high strength properties, gas silicate blocks - 500 kilograms / m³ - are applicable for the construction of both non-residential and residential facilities, reaching more than 3 floors in height. And, finally, those gas silicate blocks, whose density is 700 kg / m³, are ideal for the construction of multi-storey buildings when reinforcing row spacings, and are also used to create light floors. Builders call gas silicate blocks that do not require special care unpretentious and eternal. The autoclave block is great for those looking to reduce construction costs. The cost of aerated concrete blocks is low, in addition, the construction of a gas silicate house requires less finishing and building materials than brick. Yes, and working with gas silicate blocks is quite simple, which reduces labor costs and speeds up the process of building buildings - the construction of gas silicate blocks is carried out on average four times faster than when working with bricks.

Blocks gas silicate delivery and storage.

Blocks of gas silicate are packed by the manufacturer in a fairly durable heat-shrinkable sealed film, which reliably protects the material from moisture. Therefore, there is no need to take care of the proper protection of aerated concrete from negative atmospheric influences. The main task of the buyer, who independently transports aerated concrete blocks, is to protect them from various kinds of mechanical damage. When transported in the body, pallets with installed blocks must be rigidly fixed with soft straps, which are designed to prevent pallets with blocks from moving and friction. When unloading building materials, soft slings are also used. If aerated concrete blocks are released from the protective film and are stored in an open area, subject to precipitation - please note that the characteristics of aerated concrete blocks deteriorate from high humidity, therefore this material should be kept under a canopy or even in a closed warehouse.

Aerated concrete block masonry.

Work on the construction of buildings from aerated concrete blocks can be carried out at temperatures up to - 50 degrees; when using special frost-resistant glue. Since aerated concrete is a fairly light material, it does not cause glue to be squeezed out. Unlike brick walls made of aerated concrete can be laid out without pauses. According to building codes, gas silicate blocks with a thickness of 375 - 400 millimeters are used for laying out external walls, and at least 250 mm for interior walls. it should be slightly larger than the width of the aerated concrete blocks in the masonry. The first layer of gas silicate blocks for the purpose of leveling is placed on the mortar in order to compensate for the existing unevenness of the foundation. The laying of the gas silicate block is started from the highest building corner in terms of size. Blocks with the help of a level and a rubber hammer are leveled, polished - with a grater, after which the masonry is thoroughly cleaned of dust. Laying the very first row of gas silicate blocks should be given special attention, because the convenience of all further work and the final quality of construction depend on its evenness. You can control the laying of gas silicate blocks using a level and a cord. The next row of laying gas silicate blocks starts from any of the corners. In order to ensure maximum evenness of the rows, do not forget to use a level, and if the wall is long, also beacon intermediate blocks. Laying of rows is carried out with mandatory dressing of gas silicate blocks - that is, the displacement of each subsequent row relative to the previous ones. The minimum offset value becomes 10 centimeters. The glue that protrudes from the seams is not overwritten, but removed with a trowel. Blocks of gas silicate with a complex configuration and additional ones are made with a hacksaw for blocks.

Internal partitions from gas silicate blocks.

Regardless of which of the modern partition designs you decide to use in own house(for example, partitions made of metal profiles and drywall sheets), you will still need to make some kind of sandwich system using insulation in order to achieve the optimal level of sound insulation. And, as you know, any of the sandwich systems in terms of labor intensity is much higher and more expensive than masonry from gas silicate blocks. The problem with partitions is easily solved by aerated concrete block. For the construction of internal partitions, aerated concrete blocks are taken, having a thickness of 75 and 100 millimeters and a density of 500. As a result, the wall is quite strong, heat and sound insulated, but at the same time light.

Reinforcement when laying from gas silicate blocks.

When arranging walls in low-rise residential buildings from aerated concrete blocks, reinforcement is used, which is assigned according to a special calculation, in accordance with a specific project. As a rule, reinforcement is made through two to four rows of masonry; additionally, reinforcement is installed in the corners of buildings.

Aerated concrete blocks, therefore, is a truly economical and efficient building material, whose properties make it possible to construct buildings for various purposes in the shortest possible time. Gas silicate blocks are produced in two types: wall and partition. Both those and others are certified according to GOST. This highly environmentally friendly material is manufactured using advanced technologies using the most modern equipment, which provides the gas silicate block with the highest quality and constancy of important specifications. If you are interested in buying it, please contact the company Attribute-C , because we know everything about aerated concrete and offer our customers only high-quality gas silicate blocks, manufactured according to all technological standards and having impeccable characteristics of strength, thermal insulation, durability, etc. Attribute-C will provide you with any volume of aerated concrete blocks and, importantly, in addition to selling, we also offer you fast delivery of aerated concrete blocks with careful unloading. You will appreciate our impeccable service and prices for gas silicate blocks, which are noticeably lower than many similar organizations in the Moscow region. It is easy to order gas silicate blocks with delivery, you just need to contact us by phone 8-499-340-35-47, or send a request to the address This e-mail address is being protected from spambots. To view it you must have Javascript enabled. You can be sure that they will definitely answer you and discuss all the terms of payment and delivery of gas silicate blocks. And if you have any questions - write and get all the answers you are interested in.

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