Expanded clay fraction 20 40 technical characteristics. What are the fractions of expanded clay gravel? Expanded clay thermal conductivity by fractions

Improving building technologies is constantly moving towards increasing the strength of materials and reducing their weight. An important aspect, both in cold and hot climates, is the decrease in thermal conductivity. Expanded clay is one of the building materials in which good strength and thermal insulation properties are accumulated.

General properties of the material, its structure and types

Expanded clay is made from clay by high-temperature firing, carried out at specialized enterprises. The outer surface of clay conglomerates is melted, which ensures its smoothness and specific color. The formation of a porous structure occurs due to gases released during firing.

Clay, in various forms, is found in most important building materials - brick, cement, and a number of others. Its natural properties are characterized by high strength parameters, which expanded clay is not without. Despite the porous structure, which improves the thermal insulation properties, its compressive strength is sufficient for use in the composition of concrete, expanded clay blocks and conventional bedding.

Depending on the shape, appearance and technological process of production, expanded clay is divided into the following types:

1. expanded clay gravel- classic oval, almost round pellets or granules with a red-brown surface color - the main form of expanded clay produced. Such gravel is used everywhere in the construction industry;
2. expanded clay crushed stone- represents fragments of large expanded clay conglomerates obtained by splitting the latter. The shape of the rubble is angular and has sharp edges. The main application is limited to the addition of concretes;
3. expanded clay screenings or sand- small particles that are a by-product during firing or crushing of expanded clay and are used as a porous filler.

Gravel and crushed stone have sizes from 5 to 40 mm, and expanded clay sand is particles less than 5 mm. Small crushed fractions of expanded clay are used in water purification (filtration) systems, as well as filling in terrariums and aquariums. Such use is one of the evidence of low toxic qualities, allowing expanded clay to be put "5" for environmental friendliness.

The appearance of the material is very unpresentable, but it does not matter. Expanded clay is almost never used in open form, but is part of concrete or insulated wooden and concrete floors. The cost of expanded clay is the lowest among the available heat-insulating and structural materials, for which it deserves a rating of "5".

In the picture - a photo, a general description of expanded clay and its features

Specifications

The material parameters are set by GOST 9757-90, which regulates the quality of building porous materials. Some indicators are not regulated, but still remain an important characteristic. Let us consider in more detail the main properties of expanded clay.

• Fractional composition. In total, three fractions of the material were installed, having a size range of 5-10 mm, 10-20 mm, 20-40 mm. A separate category are fractions that are rarely used in construction work. These include expanded clay granules and crushed stone with sizes from 2.5 to 10 mm, as well as a wide mixed fraction from 5 to 20 mm. This is due to the need to fill voids in the heat-insulating layer, which increases the rigidity of the structure and eliminates convection air currents.
• Expanded clay grades by bulk density (bulk bulk density). A total of seven values ​​have been established: up to 250 kg/m3 - grade 250; from 250 to 300 kg/m3 - grade 300; upon agreement with the consumer. The true density (true volumetric weight) is 1.5-2 times greater than the bulk density. This parameter characterizes the density of the material without taking into account the gaps between the granules or fragments of the material;
• Expanded clay grades for strength. For gravel, there are 13 grades that differ in compressive strength in the cylinder. For crushed stone, 11 grades are standardized, having the same designations as grades of gravel. The strength of crushed stone and gravel of the same brand varies. So, for grade P100, the compressive strength of gravel is from 2.0 to 2.5 MPa, while crushed stone is from 1.2 to 1.6 MPa. There is a connection between expanded clay grades in terms of density and strength - an increase in density leads to an increase in strength. The relationship between grades is also regulated by the GOST 9757-90 standard, which excludes the manufacture of low-quality expanded clay of high density, which collapses under a small load.
• Compaction factor- a value agreed with the consumer, which does not exceed the value of 1.15 and is used to take into account the compaction of the expanded clay mass as a result of transportation or caking. The use of the coefficient is associated with the frequent shipment of material by bulk volume, which is convenient for the sale of large lots.
• Thermal conductivity- is the most important parameter characterizing the thermal insulation properties. For expanded clay, the thermal conductivity coefficient is from 0.10 to 0.18 W / (m? ° C). The range of values ​​is quite narrow, which indicates the high thermal insulation properties of the material. As the density increases, the thermal conductivity increases. This is due to a decrease in the number and volume of pores containing the main heat insulator - air.
• Water absorption- an important parameter showing the behavior of the material when exposed to water. Expanded clay refers to relatively resistant to materials and is characterized by a water absorption value of 8-20%.
• Soundproofing- like most heat-insulating components, expanded clay has increased sound insulation. The best results are achieved when soundproofing a wooden floor, in which expanded clay acts as a layer between the outer part of the floor and the interfloor slab.
• Frost resistance- due to low water absorption and clay, which is the basis of the material, expanded clay has sufficiently high frost-resistant properties. Numerical values ​​are not standardized by standards, since expanded clay is frost-resistant "by default". Only indicators of building stones, which contain expanded clay - expanded clay blocks, are normalized.

Disadvantages - individual parameters

The advantages of expanded clay (good strength, low thermal conductivity) are practically not affected by its individual shortcomings. Unlike numerous heat insulators, the disadvantages of expanded clay are very conditional.

These include the following:

1. increased tendency to dust formation, which is especially noticeable when working indoors. A respirator helps to solve the problem, which should always be at hand at the construction site;
2. prolonged drying of wet material - how hard expanded clay absorbs moisture, it is so difficult to get rid of it later. In order to avoid high humidity in rooms containing expanded clay, reliable moisture and vapor protection should be provided in advance.

Minor flaws, combined with high performance, allow us to evaluate the practicality of expanded clay at 4 points.

The main properties and characteristics of expanded clay gravel, as well as its pros and cons, to a greater extent depend on the correctness of the stages of its implementation.

Expanded clay alternative - expanded polystyrene and vermiculite

Expanded polystyrene (styrofoam) is an effective insulation that is successfully used in interior decoration. Its thermal conductivity is about 3 times lower than that of expanded clay. This creates, at first glance, a real alternative choice.

In reality, the methods of using these materials are different, which is caused by the high fragility of the foam boards. Insulation with expanded polystyrene is very effective, but cannot be used in places subject to mechanical stress. That is why the thermal insulation properties of foam plastic and expanded clay do not compete with each other.

Another disadvantage of polystyrene is its fire hazard. When ignited, expanded polystyrene will not only support the fire, but also release toxic gases.

Vermiculite refers to minerals expanded under the influence of high temperature and has high heat and sound insulation properties. The material is an effective replacement for expanded clay when used in the form of layers or bedding. Expanded clay is still out of competition for the production of composite blocks.

Another obstacle to the use of vermiculite is its price, which is 4-5 times higher than the cost of expanded clay. Despite the high thermal insulation properties of vermiculite, its use will be much more expensive.

Let's summarize. Expanded clay can be used for a wide range of construction tasks, including the construction of private houses and thermal insulation of apartments. High performance and relatively low price make expanded clay optimal for a modest budget. The use of expanded clay substitutes is possible, but justified only in a small number of cases.

Expanded clay gravel has high heat-saving and sound-proofing performance, which allows it to be used everywhere and to insulate various structures.

Expanded clay fraction 10-20 is used in finishing works, in the construction of roofs, and also serves as a filler in expanded clay concrete mixture and in the production of expanded clay concrete blocks. This fraction is not the largest and lightest of all presented, but it has good thermal insulation properties and can be used in almost all areas where expanded clay is needed, this is due to the universal size of the granules.

The price of expanded clay fraction 10-20

Specifications of expanded clay

LLC "Kushvinsky expanded clay plant"

Expanded clay is produced in accordance with GOST 32496-2013 "Porous Aggregates for Lightweight Concrete".

There is a sanitary-epidemiological conclusion on the content of natural radionuclides: they meet the requirements of class 1 (A eff not more than 370 Bq/kg).

Modern house impossible to imagine without insulation elements. And this determines the wide offer of the necessary materials, both in form and in composition.

Suitable as a heater "from heaven to earth". Granules insulate the roof and walls, fall asleep under the floor for the same purposes, provide thermal insulation of the foundation.

The term "claydite" implies several types of insulation, united by a common raw material for production. Gravel of three fractions, sand and crushed stone stand out.

Gravel looks like round or oval granules. It is produced by roasting fusible rocks in rotary kilns. Application features are determined by the diameter of the fraction:

• Expanded clay gravel fraction 20 - 40 mm. It has the lowest bulk density. It is used where a thick heat-insulating layer is needed: backfilling of foundations and cellars, backfilling of ceilings in attics.
• Expanded clay gravel fraction 10 - 20 mm. Serves as a heater for a roof, floors in the house and walls with a well way of a laying.
• Expanded clay gravel fraction 5 - 10 mm. Goes on filling as the basis under a "warm" floor. The grains of this fraction are used for facade insulation, when a mass of a small amount of cement and expanded clay is poured between the masonry and the facing layer.

Sand obtained by sifting clay fines and crushing large pieces of expanded clay in shaft furnaces. Areas of use:

• Expanded clay sand fraction up to 5 mm. Indispensable for laying cement screed floors.
• Expanded clay sand fraction up to 3 mm. Allows you to get a unique "warm" masonry mortar. The thermal conductivity of such a solution is 0.34 W / (m * C), and for a mixture based on quartz sand - 1.15 W / (m * C).

rubble also comes from crushing large pieces of caked clay. It is used as a filler in the production of concrete structures with a lower specific density and better heat and sound insulation.

Advantages and disadvantages of the material

As a result of the analysis of these varieties of expanded clay, the conclusion suggests itself that it is better to choose gravel as a heater. His advantage confirmed by a set of properties:

1. Durability. Retains its qualities for a long time.
2. Fire resistance. The material is absolutely non-flammable.
3. chemical inertness. Unaffected by acids and other chemicals.
4. Biostability. It is steady against formation of a fungus and does not allow to get to rodents.
5. Frost resistance. Stable with temperature fluctuations. Tolerates more than twenty shifts of freezing and thawing.
6. Low bulk density. From 250 to 800 kg/m 3 . The larger the fraction, the lower the density.
7. High strength.
8. Good heat and sound insulation. Consequence of low thermal conductivity, about 0.16 W/m and porosity.
9. Ecological purity. Does not emit harmful substances.

Worth considering separately reaction of claydite to water. It has solid water resistance and if the gravel is dried after wetting, all parameters will be restored.

But at the same time, expanded clay has a noticeable moisture absorption. Moisture-soaked gravel gains weight and loses its insulating qualities. Therefore, do not forget about waterproofing.

Important! When insulating horizontal and inclined surfaces with expanded clay gravel using the dry filling method, use a dense polyethylene film or bitumen-based roll material for vapor barrier. For tightness, the sheets are overlapped, and on the side walls they are bent to the level of the backfill.

Compare technical characteristics of various types of heaters will help table 1.

Table built from data SP-23-101-2004 and advertising sites.

gravel consumption It is not difficult to determine, given its loose form. When backfilling large arrays, you just need to calculate the required volume. And 0.1 cubic meters are spent on warming surfaces. m per layer of 10 cm per 1 m 2.

positive moment the use of expanded clay in measures for warming the home should be recognized:

• A guarantee that after completing all the work correctly, the house will be insulated for the entire period of operation.
• The material does not emit harmful substances.
• The ability to do everything with your own hands. Minimum skills required.

Coefficient of thermal conductivity expanded clay gravel is slightly higher than that of modern synthetic and mineral heaters. This implies the main drawback, which manifests itself in a significant thickness of the insulating layer and an increase in the thickness of the walls. It is advisable to take this incident into account at the design stage.

How is expanded clay insulation work performed?

Expanded clay gravel very easy to work material. It does not require any special tool. You will need shovels, buckets (stretchers), a tamping bar, a building level, as a rule, a tape measure, beacons.

Of the consumables: vapor or waterproofing, tapes, etc. for gluing seams, cement for preparation of milk.

Foundation

For foundation thermal insulation is needed to protect against annual temperature fluctuations. The technology of its protection by backfilling with expanded clay is as follows:

1. A trench is dug around the finished foundation with a depth corresponding to the amount of soil freezing. The width of the trench is at least 50 cm.
2. In the resulting cavity, formwork is placed from improvised materials (boards, slate sheets).
3. Waterproofing works are carried out along the bottom and side surfaces (film, roofing felt, etc.).
4. Expanded clay gravel is filled up to zero level, compacted. The surface is leveled.
5. From above, the insulation is also isolated from moisture.
6. Then a blind area is made around the foundation or a thin layer of soil is poured.

Floor

Isolate the floor on a concrete base from the cold from below will be obtained as a result of the phased implementation of such operations:

1. The surface is carefully prepared. All rubbish is removed and all sorts of irregularities are leveled.
2. Provides vapor barrier. The film along the perimeter is bent onto the wall to the height of the expanded clay layer.
3. Beacons indicate a given level. You can fix the rails of the beacons with small lumps of mortar.
4. Expanded clay falls asleep when the mortar sets under the strips of beacons. Better take granules of different fractions, to obtain a more durable layer.
5. The embankment is leveled by beacons with a rail or a rule. And then poured from above "cement milk".
6. The final stage is a cement screed. It is advisable to lay a reinforcing metal mesh on expanded clay in front of it. The thickness of the screed is selected at least three centimeters.

Walls

Exterior walls in the house are responsible for the preservation of heat to the greatest extent. But the technology for insulating them with expanded clay is more complicated than for the floor or ceiling. Such walls should be erected by a professional bricklayer.

Masonry in progress in two layers: internal (main) and external of facing bricks. The gap between the masonry is about ten centimeters, where expanded clay is poured. Between the masonry jumpers-ligaments are required.

Ceiling

wooden ceiling can be insulated with various materials, including expanded clay. First, the ceiling must be prepared. Check beams and ceiling boards. Replace the unusable and, if necessary, kill the boards more densely. After all, with warming, the load will also increase.

Procedure then like this:

1. We cover the structure with a vapor barrier material. The joints must be glued. Bend the edges to the height of the backfill.
2. Pour expanded clay to the height of the beam.
3. Apply a cement screed to the gravel layer or, in extreme cases, cover it with waterproofing.
4. If the attic will be used as a living space or for storage, lay a floorboard on top.

From the foregoing, we can conclude that expanded clay rightfully occupies one of the leading places among heaters.

How environmentally friendly expanded clay insulation is obtained and applied - see the video:

Expanded clay, as an environmentally friendly and inexpensive building material, is now widely used as a base for lightweight concrete, as well as an excellent thermal and sound insulator. Obtained from clayey (hydromicaceous) rocks by firing them with further processing, it differs in fractions, which determines its basic operational properties - density, thermal conductivity, etc. Today, expanded clay fraction 10-20 with a particle size of 10-20 mm, which has enviable versatility and ideally matches the quality / price ratio.

Performance characteristics and scope of use of expanded clay 10-20

The main working physical characteristics of expanded clay fraction 10-20 are as follows:

1. Bulk density - 400-500 kg/m3;
2. Strength - P75-P100;
3. Thermal conductivity - 0.094 W/ms;
4. Frost resistance - F15.

All domestic expanded clay produced at the enterprises of the construction industry complies with GOST 9757-90 and goes through a full cycle of certification by authorized official organizations.

The main field of application of expanded clay 10-20 is reliable thermal and acoustic protection of interfloor ceilings, roofs, office premises, basements, walls, etc. The material is widely used in individual construction to set the depth of laying foundations and the height of floors. It is also in demand as the basis of expanded clay concrete blocks.

Supply and packaging of expanded clay 10-20

The delivery of expanded clay grade 10-20 is carried out in bulk or in packaged form (in standard bags). When shipped in bulk, calculations for it are carried out based on the number of cubic meters of the released material, when shipped in bags - based on the cost of a full bag.

In case of wholesale deliveries, which allow the buyer to save significantly, the minimum number of bags (volume) of expanded clay is initially specified, at which the wholesale price is valid.

The material parameters are set by GOST 9757-90, which regulates the quality of building porous materials. Some indicators are not regulated, but still remain an important characteristic. Let us consider in more detail the main properties of expanded clay.

• Fractional composition. In total, three fractions of the material were installed, having a size range of 5-10 mm, 10-20 mm, 20-40 mm. A separate category are fractions that are rarely used in construction work. These include expanded clay granules and crushed stone with sizes from 2.5 to 10 mm, as well as a wide mixed fraction from 5 to 20 mm. This is due to the need to fill voids in the heat-insulating layer, which increases the rigidity of the structure and eliminates convection air currents.
• Expanded clay grades by bulk density (bulk bulk density). In total, seven values ​​​​are set: up to 250 kg / m3 - grade 250, from 250 to 300 kg / m3 - grade 300, similarly - grades 350, 400, 450, 500, 600. Grades 700 and 800 are not produced for general sale and are produced only upon agreement with the consumer. The true density (true volumetric weight) is 1.5-2 times greater than the bulk density. This parameter characterizes the density of the material without taking into account the gaps between the granules or fragments of the material;
• Expanded clay grades for strength. For gravel, there are 13 grades that differ in compressive strength in the cylinder. For crushed stone, 11 grades are standardized, having the same designations as grades of gravel. The strength of crushed stone and gravel of the same brand varies. So, for grade P100, the compressive strength of gravel is from 2.0 to 2.5 MPa, while crushed stone is from 1.2 to 1.6 MPa. There is a connection between expanded clay grades in terms of density and strength - an increase in density leads to an increase in strength. The relationship between grades is also regulated by the GOST 9757-90 standard, which excludes the manufacture of low-quality expanded clay of high density, which collapses under a small load.
• Compaction factor- a value agreed with the consumer, which does not exceed the value of 1.15 and is used to take into account the compaction of the expanded clay mass as a result of transportation or caking. The use of the coefficient is associated with the frequent shipment of material by bulk volume, which is convenient for the sale of large lots.
• Thermal conductivity- is the most important parameter characterizing the thermal insulation properties. For expanded clay, the thermal conductivity coefficient is from 0.10 to 0.18 W / (m? ° C). The range of values ​​is quite narrow, which indicates the high thermal insulation properties of the material. As the density increases, the thermal conductivity increases. This is due to a decrease in the number and volume of pores containing the main heat insulator - air.
• Water absorption- an important parameter showing the behavior of the material when exposed to water. Expanded clay refers to relatively resistant to materials and is characterized by a water absorption value of 8-20%.
• Soundproofing- like most heat-insulating components, expanded clay has increased sound insulation. The best results are achieved when soundproofing a wooden floor, in which expanded clay acts as a layer between the outer part of the floor and the interfloor slab.
• Frost resistance- due to low water absorption and clay, which is the basis of the material, expanded clay has sufficiently high frost-resistant properties. Numerical values ​​are not standardized by standards, since expanded clay is frost-resistant "by default". Only indicators of building stones, which contain expanded clay - expanded clay blocks, are normalized.