The role of emotions in the teacher's work. Emotions and their role in the educational process

We think that many of the users will agree with the argument that timber is rightfully considered one of the most popular types of lumber used in the construction of houses. It is difficult to imagine the entire list of construction areas where it is used. You can learn how to properly approach the construction of a log house from our forum. But today, the classics of wooden housing construction are being replaced by a new material - composite timber.

Having read the name for the first time, or taking this material in hand, many of the developers may think:

“It looks like wood, only lighter and stronger. What is it made of?"

This material appeared on the market relatively recently, and in essence is not a real tree, although it has all the advantages of a conventional timber. But as they say:

“Everything new is a well-forgotten old.”

One has only to look at plywood, which is well known to us, or remember how in ancient times houses were built from blocks, mixing straw and clay with each other, in order to understand the essence of the composite material.

A composite is an artificially created solid material consisting of two or more components with different physical and chemical properties.

And if the use of composite materials in modern technology does not surprise anyone, then a beam - created from a composite, may cause surprise or distrust of the developer.

What is it - a composite beam?

The basis of the composite timber is made up of small particles of natural wood, special additives and dyes that give a rich color to the composite timber.

The connecting link of the above substances is bischofite. By the way, remember interesting fact about bischofite.

In addition to the fact that this mineral is used in the production of tiles and artificial stone, it has found application in medicine for the treatment of joints and upper respiratory tract, which means that houses built from composite timber will be environmentally friendly and even healing.

How is composite timber made?

The manufacture of composite timber is characterized by simplicity and manufacturability of the process.

Pre-prepared and carefully mixed raw materials are pressed, after which the resulting material is cut into a beam of strictly specified dimensions.

Special additives give the composite beam water resistance and fire resistance. Despite its increased hardness, the composite beam retained all positive sides work with natural wood.

It is perfectly sawn, cut and easily connected with metal fasteners.

Benefits of composite timber

Due to the construction of the "comb-groove" beam, the construction of a house does not resemble construction, but the assembly of a building according to the principle of a children's designer. A cement composition is pre-applied on one side of the beam, and the beam is connected to each other. After that, it remains only to cover the seams. Usually they are covered with a mixture of bischofite and magnesite. As a result, the erected building acquires additional strength and tightness.

Possessing all the advantages of natural wood, the composite timber is free from such disadvantages as shrinkage and swelling.

If you pick up a composite beam, and then a regular planed one, you can notice the difference in weight. This is another advantage of the composite beam. Houses built from it are lighter, which means that there is no need to build a powerful foundation, which leads to saving your money. The intricacies of pouring a strip foundation are shared by our forum member in the forum.

Summarizing

In conclusion, it is worth mentioning such important characteristics of composite timber as high fire resistance. According to this indicator, he is included in the same group with a brick.

And in terms of thermal conductivity, it surpasses ordinary timber, which allows it to effectively retain heat and protect the room from the cold.

It should also be noted that a house built from a composite beam is not subject to decay, rodents will not start in it, and the walls themselves do not have to be plastered.

A heated discussion on rodent control is underway

It would seem that here it is - an ideal building material. But as they say, every medal has a flip side. The production of such material requires the use of expensive equipment and rare materials, which affects the price of composite timber, which exceeds the cost of planed timber and comes close to the price of glued timber.

There is another problem that should be taken into account by those who are interested in this material - due to the short life of houses built using this technology, it is difficult to predict how the structure will behave in the near future.

After reviewing the readers will be able to avoid mistakes in the construction of a log house. And looking at this video , you will learn how to decorate the facade of a wooden house.

The scope of application of composites and volumes are constantly growing, replacing the use of traditional building materials from metal, such as rebar, masonry reinforcing mesh, flexible connections, profile

What is composite material?

Composite materials include materials made from several components (natural or artificial) that differ in their properties, when combined together, a synergistic effect is obtained. As a result, such materials are superior to conventional ones in several parameters: strength, durability, resistance to aggressive environments, weight, thermal conductivity and cost.

Using composite materials when building, you will always win!

Construction modern buildings and structures involves the use of the most efficient materials, so composites based on fiberglass, basalt and carbon fiber are becoming more and more in demand. There are a number of reasons for this:

- High strength of products made of composites, which is not inferior, but in a number of parameters surpasses similar metal ones. Composite products have high tensile strength, compressive strength, shear strength, and torsion strength.
- With the same strength, products made of composite materials are several times lighter (when compared with metal ones). This significantly reduces transportation costs, reduces the complexity of installation and the load on the foundation of buildings.
— Composite materials serve equally well both indoors and outdoors. Neither direct sunlight, nor precipitation, nor sudden changes in temperature have a negative effect on modern designs from composites. Therefore, composite beams can also be used for the construction of structures that are open to the external environment without special processing.
- When working in aggressive environments composite materials do not change their properties under the influence of the most active chemical reagents. fiberglass profile, used for the construction of a warehouse in which acids or alkalis are stored, will remain in the same shape and will have the same properties as before the start of operation of the premises. Reinforcement made of composites in concrete with antifreeze additives will not undergo accelerated corrosion.
— Composite materials are not magnetic and do not conduct electricity, which prevents the occurrence of electrochemical corrosion, in buildings with the replacement of metal reinforcement with a composite one, the shielding effect of the "Faraday cage" is reduced.
- Composite elements in the building structure do not create cold bridges, thereby increasing the overall thermal resistance.

Today, Russia's GDP is 3.3% of world GDP. At the same time, the level of production and consumption of composite materials in Russia is less than 1% of the world level. Composites are the material of the future and a strategic challenge for Russian economy to provide a breakthrough in this area.

In our online store you can buy with delivery in Moscow a wide range of products from composite materials (composite plastic reinforcement, composite construction mesh, road composite mesh, composite geogrid, composite flexible connections, composite building connections, composite profile), from the best domestic manufacturers with whom we have established good partnerships and for quality products of which we are sure.

Send your good work in the knowledge base is simple. Use the form below

Students, graduate students, young scientists who use the knowledge base in their studies and work will be very grateful to you.

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Introduction
1. General information about composite materials
2. Composition and structure of the composite
3. Evaluation of the matrix and hardener in the formation of the properties of the composite
3.1 Metal matrix composite materials
3.2 Composite materials with a non-metallic matrix
4. Building materials - composites
4.1 Polymers in construction
4.2 Composites and concrete
4.3 Aluminum composite panels
Conclusion
List of used literature
INTRODUCTION
At the beginning of the 21st century, the question of future building materials is being asked. The rapid development of science and technology makes it difficult to predict: four decades ago there was no widespread use of polymeric building materials, and modern "true" composites were known only to a narrow circle of specialists. However, it can be assumed that the main building materials will also be metal, concrete and reinforced concrete, ceramics, glass, wood, and polymers. Building materials will be created on the same raw material basis, but with the use of new formulations of components and technological methods, which will give a higher operational quality and hence durability and reliability. There will be maximum use of waste from various industries, used products, local and domestic waste. Building materials will be selected according to environmental criteria and their production will be based on waste-free technologies.
Already now there is an abundance of brand names for finishing, insulating and other materials, which, in principle, differ only in composition and technology. This flow of new materials will increase and their performance will improve in response to the harsh climatic conditions and savings energy resources Russia.
1. GENERAL INFORMATION ABOUT COMPOSITE MATERIALS
Composite material is a heterogeneous solid material consisting of two or more components, among which reinforcing elements can be distinguished that provide the necessary mechanical characteristics material, and a matrix (or binder) that ensures the joint work of the reinforcing elements.
The mechanical behavior of the composite is determined by the ratio of the properties of the reinforcing elements and the matrix, as well as the strength of the bond between them. The efficiency and performance of the material depends on right choice original components and the technology of their combination, designed to provide a strong connection between the components while maintaining their original characteristics.
As a result of combining the reinforcing elements and the matrix, a complex of composite properties is formed, which not only reflects the initial characteristics of its components, but also includes properties that isolated components do not possess. In particular, the presence of interfaces between the reinforcing elements and the matrix significantly increases the crack resistance of the material, and in composites, unlike metals, an increase in static strength does not lead to a decrease, but, as a rule, to an increase in fracture toughness characteristics.
Advantages of composite materials:
high specific strength
high rigidity (modulus of elasticity 130-140 GPa)
high wear resistance
high fatigue strength
it is possible to make dimensionally stable structures from CM
Moreover, different classes composites may have one or more advantages. Some benefits cannot be achieved simultaneously.
Disadvantages of composite materials
Most classes of composites (but not all) have disadvantages:
high price
property anisotropy
increased science intensity of production, the need for special expensive equipment and raw materials, and therefore a developed industrial production and scientific base of the country
2. COMPOSITE AND STRUCTURE OF THE COMPOSITE
Composites are multicomponent materials consisting of a polymer, metal, carbon, ceramic or other base (matrix) reinforced with fillers made of fibers, whiskers, fine particles, etc. By selecting the composition and properties of the filler and matrix (binder), their ratio , orientation of the filler, it is possible to obtain materials with the required combination of operational and technological properties. The use of several matrices (polymatrix composite materials) or fillers of various nature (hybrid composite materials) in one material significantly expands the possibilities for controlling the properties of composite materials. Reinforcing fillers perceive the main share of the load of composite materials.
According to the structure of the filler, composite materials are divided into fibrous (reinforced with fibers and whiskers), layered (reinforced with films, plates, layered fillers), dispersion-reinforced, or dispersion-strengthened (with a filler in the form of fine particles). The matrix in composite materials ensures the solidity of the material, the transfer and distribution of stress in the filler, determines the heat, moisture, fire and chemical. durability.
According to the nature of the matrix material, polymer, metal, carbon, ceramic, and other composites are distinguished.
Composite materials reinforced with high-strength and high-modulus continuous fibers have received the greatest application in construction and engineering. These include: polymer composite materials based on thermosetting (epoxy, polyester, phenol-formal, polyamide, etc.) and thermoplastic binders reinforced with glass (fiberglass), carbon (carbon fiber), org. (organoplasty), boron (boroplasty) and other fibers; metallic composite materials based on Al, Mg, Cu, Ti, Ni, Cr alloys reinforced with boron, carbon or silicon carbide fibers, as well as steel, molybdenum or tungsten wire;
Composite materials based on carbon reinforced with carbon fibers (carbon-carbon materials); composite materials based on ceramics reinforced with carbon, silicon carbide and other heat-resistant fibers and SiC. When using carbon, glass, aramid and boron fibers contained in the material in the amount of 50-70%, compositions were created (see table) with beats. strength and modulus of elasticity are 2-5 times greater than those of conventional structural materials and alloys. In addition, fibrous composite materials are superior to metals and alloys in terms of fatigue strength, heat resistance, vibration resistance, noise absorption, impact strength, and other properties. Thus, the reinforcement of Al alloys with boron fibers significantly improves their mechanical characteristics and makes it possible to increase the operating temperature of the alloy from 250–300 to 450–500 °C. Reinforcement with wire (from W and Mo) and fibers of refractory compounds is used to create heat-resistant composite materials based on Ni, Cr, Co, Ti and their alloys. So, heat-resistant Ni alloys reinforced with fibers can operate at 1300-1350 °C. In the manufacture of metallic fibrous composite materials, the application of a metal matrix to a filler is carried out mainly from a melt of the matrix material, by electrochemical deposition or sputtering. The molding of products is carried out by Ch. arr. the method of impregnating the frame of reinforcing fibers with a metal melt under pressure up to 10 MPa or by combining foil (matrix material) with reinforcing fibers using rolling, pressing, extrusion under load. up to the melting temperature of the matrix material.
One of the common technological methods production of polymer and metal. fibrous and layered composite materials - the growth of filler crystals in the matrix directly in the process of manufacturing parts. This method is used, for example, when creating eutectic. heat-resistant alloys based on Ni and Co. Alloying of melts with carbide and intermetallic. Comm., which form fibrous or lamellar crystals during cooling under controlled conditions, leads to hardening of alloys and allows you to increase the temperature of their operation by 60-80 oC. carbon-based composite materials combine low density with high thermal conductivity, chem. durability, constancy of dimensions with sharp drops in temperature, as well as with an increase in strength and modulus of elasticity when heated to 2000 ° C in an inert medium. For methods of obtaining carbon-carbon composite materials, see CFRP. High-strength composite materials based on ceramics are obtained by reinforcing with fibrous fillers, as well as metal. and ceramic dispersed particles. Reinforcement with continuous SiC fibers makes it possible to obtain composite materials characterized by an increase in toughness, flexural strength and high resistance to oxidation at high temperatures. However, the reinforcement of ceramics with fibers does not always lead to significant results. an increase in its strength properties due to the lack of an elastic state of the material when high value its modulus of elasticity. Reinforcement with dispersed metal. particles allows you to create a ceramic-metal. materials (cermets) with increased. strength, thermal conductivity, thermal shock resistance. In the manufacture of ceramic composite materials usually use hot pressing, pressing with the last. sintering, slip casting (see also Ceramics). Reinforcement of materials with dispersed metallic. particles leads to a sharp increase in strength due to the creation of barriers to the movement of dislocations. Such reinforcement arr. used in the creation of heat-resistant chromium-nickel alloys. Materials are obtained by introducing fine particles into the molten metal with the last. normal processing of ingots into products. The introduction of, for example, ThO2 or ZrO2 into the alloy makes it possible to obtain dispersion-strengthened heat-resistant alloys that work for a long time under load at 1100-1200 ° C (the working capacity limit of conventional heat-resistant alloys under the same conditions is 1000-1050 ° C). A promising direction in the creation of high-strength composite materials is the reinforcement of materials with whiskers, which, due to their small diameter, are practically devoid of defects found in larger crystals and have high strength. max. practical of interest are crystals of Al2O3, BeO, SiC, B4C, Si3N4, AlN and graphite with a diameter of 1-30 microns and a length of 0.3-15 mm. Such fillers are used in the form of oriented yarn or isotropic laminates like paper, cardboard, felt. Composite materials based on an epoxy matrix and ThO2 whiskers (30% by weight) have a dist of 0.6 GPa and an elastic modulus of 70 GPa. The introduction of whiskers into the composition can give it unusual combinations of electrical and magnetic properties. The choice and appointment of composite materials are largely determined by the loading conditions and operating conditions of the part or structure, technol. opportunities. the most accessible and mastered polymer composite materials Large range of matrices in the form of thermosetting and thermoplastic. polymers provides a wide range of composite materials for operation ranging from negative. t-r up to 100-200°С - for organoplastics, up to 300-400 °С - for glass-, carbon- and boron-plastics. Polymer composite materials with a polyester and epoxy matrix work up to 120-200 °, with a phenol-formaldehyde - up to 200-300 ° C, polyimide and silicon-org. - up to 250-400°C. metallic composite materials based on Al, Mg and their alloys, reinforced with fibers from B, C, SiC, are used up to 400-500°C; composite materials based on Ni and Co alloys operate at temperatures up to 1100-1200 ° C, based on refractory metals and Comm. - up to 1500-1700°C, based on carbon and ceramics - up to 1700-2000°C. The use of composites as structural, heat-shielding, antifriction, radio and electrical engineering. and other materials makes it possible to reduce the weight of the structure, increase the resources and capacities of machines and assemblies, and create fundamentally new units, parts and structures. All types of composite materials are used in chemical, textile, mining, metallurgical industry, mechanical engineering, transport, for the manufacture of sports equipment, etc.
composite polymer aluminum construction
3. EVALUATION OF THE MATRIX AND HARDENER IN THE FORMATION OF COMPOSITE PROPERTIES
3.1 COMPOSITE MATERIALS WITH METAL MATRIX
Composite materials consist of a metal matrix (more often Al, Mg, Ni and their alloys) reinforced with high-strength fibers (fibrous materials) or finely dispersed refractory particles that do not dissolve in the base metal (dispersion-strengthened materials). The metal matrix binds the fibers (dispersed particles) into a single whole. Fiber (dispersed particles) plus a binder (matrix) that make up a particular composition are called composite materials.
3.2 COMPOSITE MATERIALS WITH A NON-METALLIC MATRIX
Composite materials with a non-metallic matrix have found wide application. Polymer, carbon and ceramic materials are used as non-metallic matrices. From polymer matrices most widespread received epoxy, phenol-formaldehyde and polyamide. Carbon matrices coked or pyrocarbon obtained from synthetic polymers subjected to pyrolysis. The matrix binds the composition, giving it form. Strengtheners are fibers: glass, carbon, boron, organic, based on whiskers (oxides, carbides, borides, nitrides, and others), as well as metal (wires), which have high strength and rigidity. The properties of composite materials depend on the composition of the components, their combination, quantitative ratio and bond strength between them. Reinforcing materials can be in the form of fibers, tows, threads, tapes, multilayer fabrics. The content of the hardener in oriented materials is 60-80 vol.%, in non-oriented (with discrete fibers and whiskers) 20-30 vol.%. The higher the strength and modulus of elasticity of the fibers, the higher the strength and stiffness of the composite material. The properties of the matrix determine the strength of the composition in shear and compression and resistance to fatigue failure. According to the type of hardener, composite materials are classified into glass fibers, carbon fibers with carbon fibers, boron fibers and organ fibers. In laminated materials, fibers, threads, tapes impregnated with a binder are laid parallel to each other in the laying plane. Flat layers are assembled into plates. The properties are anisotropic. For the work of the material in the product, it is important to take into account the direction of the acting loads. You can create materials with both isotropic and anisotropic properties. You can lay the fibers at different angles, varying the properties of composite materials. The bending and torsional stiffness of the material depends on the order of laying the layers along the thickness of the package. The laying of reinforcing elements of three, four or more threads is used. The structure of three mutually perpendicular threads has the greatest application. Hardeners can be located in axial, radial and circumferential directions. Three-dimensional materials can be of any thickness in the form of blocks, cylinders. Bulky fabrics increase peel strength and shear resistance compared to layered fabrics. A system of four strands is built by expanding the reinforcing agent along the diagonals of the cube. The structure of four threads is balanced, has increased shear rigidity in the main planes. However, creating four-directional materials is more difficult than three-directional ones.
4 . BUILDING MATERIALS - COMPOSITES
4.1 POLYMERS IN CONSTRUCTION
Speaking about the use of new materials based on plastics in the construction industry, it is worth noting the following. While civil engineering mainly uses “traditional” materials, sectors such as bridge construction, railways, bridges, etc., polymer composites have good prospects.
Construction is a vague term that includes a wide variety of mechanical stresses, from light loads that are subjected to shields, enclosures, equipment protection nests or soundproof walls, to ultra-high pressures that bridge piers withstand. To find solutions applicable to these dissimilar situations, civil engineering uses refined plastics or composites:
- Commonly used in light building structures.
- Occasionally used in specialized (niche) structures - Designed exclusively for large building structures, such as bridges.
Figure 1 shows a few examples.
Figure 1: Building structures in civil engineering .
Civil engineering uses traditional materials such as concrete and steel, which are characterized by low component costs, but high processing and installation costs, and low processing capabilities. The result of the introduction of plastics can be the following :
- Reduction of final expenses.
- Productivity increase.
- Weight loss.
- Increased design possibilities compared to wood and metals.
- Corrosion resistance.
- Easy handling and installation.
- Certain polymers can transmit light and even be transparent.
- Ease of maintenance.
- Insulating properties.
On the other hand, aging and mechanical resistance should be kept in mind. However, some designs built in the mid-1950s using fiberglass reinforced polyester show significant durability.
Industry civil engineering is conservative, and there are barriers to the expansion of the use of plastics and composites, such as :
- Poor knowledge and little experience with these materials in the civil engineering industry.
- Difficulty in transferring experience gained in other industries.
- Difficulty in selecting and sizing these materials.
- The complexity of mutual understanding between representatives of different professions with very different mentalities.
- Public opinion about plastics.
- Harsh environmental conditions at the construction site.
- Difficult conditions applications that do not quite match the practice and qualifications of builders.
The progressive response of plastics to the growing demands of construction: from refined thermoplastics to oriented carbon fiber composites Composites are of particular interest to the construction industry due to their inherent high odds[performance / weight / final cost].
Moreover, the ability to specify direction in composite reinforcement provides more design options than steel.
Table 1 compares several cases, but other intermediate solutions also exist.
Table 1: Examples of Properties from Refined Thermoplastics to Unidirectional Composites

Cleaned plastics and plastics reinforced with short fiberglass
Characteristic	Reaction injection molded polyurethane	Polymethyl methacrylate for soundproof walls
Fiberglass,%
Density, g/cm3
Tensile strength, MPa
Elongation at break,%
Bending modulus, GPa

Izod notch impact, kJ/m2
Glass fiber reinforced thermosetting plastic for BMC (glass-filled molding premix) and SMC (sheet molding material)
Characteristic
fiberglass weight
Density, g/cm3
Tensile strength, MPa
Elongation at break,%
Bending modulus, GPa
Izod notch impact, J/m
Epoxy resin reinforced with unidirectional carbon fiber
Weight of carbon fiber,%
Density, g/cm3
Tensile strength, MPa
Elongation at break,%
Bending modulus, GPa

Figure 2 shows a diagram of the increase in mechanical efficiency in accordance with the reinforcement of the polymer.

Figure 2: Mechanical performance of plastics.

Material costs for composites always outweigh those for metal, with carbon fiber reinforcement being the most expensive (see Figure 3). These costs for plastics and composites are offset by other benefits.

Figure 3: Comparative cost of composites and metal.

In exchange for the high cost of the material, composites offer a unique set of interesting properties:

Reduced weight - Reduced assembly costs - Installation - Reduced operating costs - Reduced final costs - Corrosion resistance - Safety.

Weight reduction The density of steel exceeds the density of composites by the following factors:

3.9 vs glass fiber reinforced epoxy.

5.1 vs carbon fiber reinforced epoxy.

5.8 vs Kevlar fiber reinforced epoxy.

The potential for weight savings if composites are used instead of steel is less significant. In most currently proposed solutions, they can be estimated at approximately 15-30%.

4.2 COMPOSITES AND CONCRETE

The advantages of composite materials are well manifested in the reinforcement of concrete and construction.

Inexpensive and versatile, concrete is one of the best building materials on offer. Being a true composite, typical concrete consists of gravel and sand bonded together in a matrix of cement, with metal reinforcement usually added to enhance strength. Concrete is excellent in compression, but becomes brittle and weak in tension. Tensile stresses, as well as plastic shrinkage during curing, lead to cracks that absorb water, which ultimately leads to corrosion of the metal reinforcement and a significant loss of concrete solidity when the metal fails.

Composite rebar has established itself in the construction market due to its proven corrosion resistance. New and updated design guidelines and test protocols make it easier for engineers to select reinforced plastics.

Fibre-reinforced plastics (fiberglass, basalt) have long been considered as materials to improve the performance of concrete.

Composite rebar: established technology.

Over the past 15 years, composite rebar has gone from being an experimental prototype to being a viable substitute for steel in many projects, especially as steel prices rise. "Fiberglass rebar is used a lot and it's a very competitive market."

For some engineering projects, such as MRI equipment in hospitals, or approaching toll booths that use RFID technology to identify paid customers, composite rebar is the only choice. Steel reinforcement cannot be used because it interferes with electromagnetic signals. In addition to being electromagnetically transparent, composite rebar is also remarkably resistant to corrosion, is light in weight—about one-fourth that of steel, and is a thermal insulator because it prevents heat from flowing into building structures.

Composite meshes in precast concrete panels: high potential C-GRID carbon epoxy meshes are replacing traditional steel or rebar in precast structures as secondary reinforcement.

C-GRID is a coarse grid of carbon/epoxy resin tows. Used as a replacement for secondary steel mesh in concrete panels and architectural applications. Mesh size varies depending on concrete and aggregate type as well as panel strength requirements

Fibre-reinforced concrete: the appearance of strength.

The use of short fibers in concrete to improve its properties has been an established technology for decades, and even centuries, considering that in the Roman Empire, mortars were reinforced with horsehair. Fiber reinforcement enhances the strength and elasticity of concrete (the ability to plastically deform without breaking) by holding part of the load when the matrix is damaged and preventing crack growth.

"The addition of fibers allows the material to deform plastically and withstand tensile loads."

Fibre-reinforced concrete was used to make these prestressed bridge girders. The use of reinforcement was not required due to the high elasticity and strength of the material, which was given to it by steel reinforcing fibers added to the concrete mixture.

4.3 ALUMINUM COMPOSITE PANELS

Aluminum composite material is a panel consisting of two aluminum sheets and a plastic or mineral filler between them. The composite structure of the material gives it lightness and high strength, combined with elasticity and fracture resistance. Chemical and paint surface treatment provides the material with excellent resistance to corrosion and temperature fluctuations. Due to the combination of these unique properties, aluminum composite material is one of the most sought after in construction.

The aluminum composite has a number of significant advantages that ensure its growing popularity as a finishing material every year.

Minimum weight combined with high rigidity. AKM panels are distinguished by low weight due to the use of aluminum cover sheets and a lightweight core layer, combined with high rigidity given by the combination of the above materials. In terms of application on facade structures this circumstance distinguishes AKM from alternative materials such as sheet aluminum and steel, ceramic granite, fiber cement boards. The use of aluminum composite material significantly reduces the overall weight of the ventilated façade structure.

flatness of the material. The aluminum composite material is able to resist twisting. The reason is the application of the top layer by rolling. The flatness is ensured by the use of rolling instead of conventional pressing, which gives a high uniformity in the application of the layer. The maximum flatness is 2mm per 1220mm length, which is 0.16% of the latter.

Resistance of a paint and varnish covering to influence of environment. Due to the extremely stable multi-layer coating, the material does not lose its color intensity for a long time under the influence of sunny color and aggressive components of the atmosphere.

Wide selection of colors and textures. The material is produced with a coating made of paints: solid colors and metallic colors in any range of colors and shades, stone and wood effect coatings. In addition, panels with a coating of "chrome", "gold", panels with a textured surface, panels with a polished coating of stainless steel, titanium, and copper are produced.

General wear resistance. AKM panels have complex structure formed by aluminum sheets and filler of the central layer. The conjugation of these materials provides the panels with rigidity combined with elasticity, which makes AKM resistant to loads and deformations created environment. The material does not lose its properties for an extremely long time.

Corrosion resistance. The resistance of the material to corrosion is determined by the use of aluminum alloy sheets in the structure of the panel, protected by a multi-layer paint and varnish coating. In case of damage to the coating, the surface of the sheet is protected by the formation of an oxide film.

Soundproof properties. The composite structure of the AKM panel provides good sound insulation, absorbing sound waves and vibration.

Material workability. Panels easily lend themselves to such types machining such as bending, cutting, milling, drilling, rolling, welding, gluing, without compromising the coating and violating the structure of the material. Under loads arising in the process of panel bending, including in the radius, there is no delamination of panels or violations of surface layers, such as cracking of aluminum sheets and paintwork. During production at the factory, the panels are protected from mechanical damage with a special film, which is removed after completion of the installation work.

Shaping. Panels easily take almost any given shape, such as radius. The suitability of the material for soldering makes it possible to achieve complex geometry of products, which is impossible with any other facing material, except for aluminum, in front of which AKM is significantly superior in weight.

Aesthetic design. The use of aluminum composite material allows the creation of cladding panels of various sizes and shapes, makes given material indispensable in solving complex architectural problems.

Long service life. AKM for a long time are resistant to environmental influences, such as sunlight, atmospheric precipitation, wind loads, temperature fluctuations, thanks to the use of a stable coating and the combination of rigidity and elasticity achieved in the material. The estimated lifetime of the panels outdoors is about 50 years.

Minimum maintenance during operation. The presence of a high-quality coating contributes to the self-cleaning of the panels from external contaminants. Also, the panels are easy to clean with non-aggressive cleaners.

CONCLUSION

Two promising avenues are opened up by composite materials reinforced with either fibers or dispersed solids.

In the former, the thinnest high-strength fibers made of glass, carbon, boron, beryllium, steel, or whisker single crystals are introduced into an inorganic metal or organic polymer matrix. As a result of this combination, maximum strength is combined with a high modulus of elasticity and low density. Composite materials are such materials of the future.

Composite material is a structural (metallic or non-metallic) material in which there are reinforcing elements in the form of threads, fibers or flakes of a more durable material. Examples of composite materials: plastic reinforced with boron, carbon, glass fibers, tows or fabrics based on them; aluminum reinforced with steel filaments, beryllium.

Combining the volume content of the components, it is possible to obtain composite materials with the required values of strength, heat resistance, elastic modulus, abrasive resistance, as well as create compositions with the necessary magnetic, dielectric, radio absorbing and other special properties.

LIST OF USED LITERATURE

Gorchakov G.I., Bazhenov Yu.M. Construction Materials. - M.: Stroyizdat, 1986.

Mikulsky V.G., Gorchakov G.I., Kozlov V.V., Kupriyanov V.N., Orentlicher L.P., Rakhimov R.Z., Sakharov G.P., Khrulev V.M. Building materials / Under the editorship of V.G. Mikulsky. - M.: ASV, 1996, 2000.

Rybyev I.A., Arefieva T.N., Baskakov N.S., Kazenova E.P., Korovnikov B.D., Rybyeva T.G. General course building materials / Ed. I.A. Rybyeva. M.: graduate School, 1987.

Higerovich M.I., Gorchakov G.I., Rybiev I.A., Domokeev A.G., Erofeeva E.A., Orentlicher L.P., Popov L.N., Popov K.N. Building materials / Under the editorship of G.I. Gorchakov. - M: Higher School, 1982.

Evald V.V. Building materials, their manufacture, properties and testing. - S. -Pb. -L. -M: 1896-1933, 14th ed.

Composite materials of fibrous structure. K., 1970.

Konkin A.A., Carbon and other heat-resistant fibrous materials, M., 1974.

Composite materials, trans. from English, vol. 1-8, M., 1978.

Fillers for polymeric composite materials, lane. from English, M., 1981.

Saifulin R.S., Inorganic composite materials, M., 1983.

Handbook of composite materials, ed.D. Lubina, trans. from English, book. I 2, M., 1988.

The main directions of development of composite thermoplastic materials, M. . 1988.

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General information about building materials. The influence of various factors on the properties of concrete mixtures. Composition, manufacturing technology and application in construction of roofing ceramic materials, drainage and sewer pipes, aggregates for concrete.

control work, added 07/05/2010

General information about building materials. The structure and chemical composition of concrete, its physical and mechanical properties. Most known species brick, its visual and geometric characteristics. Moisture content of wood and related properties.

presentation, added 02/19/2014

The history of building aluminum alloys, their physical and mechanical properties, assortments, means of connection. Basic principles of designing aluminum structures in construction. Features of welding, riveting, bolted and adhesive joints.

term paper, added 12/13/2011

Effective application brickwork in construction. "Ventilation" of the combined walls. Heat-efficient enclosing structures of residential and civil buildings. Physical bases of standardization of thermotechnical properties of ceramic bricks and stone.

term paper, added 02/04/2012

Classification of building materials. Requirements for the components of concrete, factors affecting its strength and workability. Cellular and porous concretes, their application in construction. Paints and varnishes and metals, their use in construction.

test, added 05/05/2014

Structural solution 9-storey panel residential building. The main materials used in industrial construction. Panels for external walls. Structural elements of residential buildings. Methods for laying bricks. The nomenclature of the plant of reinforced concrete products.

practice report, added 06/22/2015

The use of wood in construction, evaluation of its positive and negative properties. Means of connecting elements of wooden structures. Calculation of the structures of the working platform, shield and roof girders, glued beams, centrally compressed rack (column).

term paper, added 03/12/2015

General information about facing materials. Functional Features panels based on chipboard, fiberboard, MDF, as well as materials used for wall decoration. Decorative plaster, plastic panels. Non-traditional materials for interior decoration.

The use of composite materials in construction

Fibre-reinforced plastics (fiberglass, basalt) have long been considered as materials to improve the performance of concrete.

Over the past 15 years, composite rebar has gone from being an experimental prototype to being a viable substitute for steel in many projects, especially as steel prices rise.

Composite meshes in precast concrete panels: high potential C-GRID carbon epoxy meshes are replacing traditional steel or rebar in precast structures as secondary reinforcement.

The addition of fibers allows the material to deform plastically and withstand tensile loads.

The aluminum composite has a number of significant advantages that ensure its growing popularity as a finishing material every year.

Minimum weight combined with high rigidity. The aluminum composite panels are characterized by low weight due to the use of aluminum cover sheets and a lightweight core layer combined with high rigidity given by the combination of the above materials. In terms of application on facade structures, this circumstance favorably distinguishes aluminum composite materials from alternative materials, such as sheet aluminum and steel, ceramic granite, fiber cement boards. The use of aluminum composite material significantly reduces the overall weight of the ventilated facade structure. composite concrete aluminum metal

The aluminum composite material is able to resist twisting. The reason is the application of the top layer by rolling. The flatness is ensured by the use of rolling instead of conventional pressing, which gives a high uniformity in the application of the layer. The maximum flatness is 2mm per 1220mm length, which is 0.16% of the latter.

- The resistance of the paintwork to environmental influences. Due to the extremely stable multi-layer coating, the material does not lose color intensity for a long time under the influence of sunlight and aggressive atmospheric components.
- Wide range of colors and textures. The material is produced with a coating made of lacquers: solid colors and metallic colors in any range of colors and shades, stone and wood effect coatings. In addition, panels with a coating of "chrome", "gold", panels with a textured surface, panels with a polished coating of stainless steel, titanium, and copper are produced.

The aluminum composite material panels have a complex structure formed by aluminum sheets and core core filler. The pairing of these materials provides the panels with rigidity combined with elasticity, which makes aluminum composite materials resistant to environmental loads and deformations. The material does not lose its properties for an extremely long time.

The resistance of the material to corrosion is determined by the use of aluminum alloy sheets in the structure of the panel, protected by a multilayer paint and varnish coating. In case of damage to the coating, the surface of the sheet is protected by the formation of an oxide film.

The composite structure of the aluminum composite material panel provides good sound insulation by absorbing sound waves and vibrations.

The panels are easily amenable to such types of mechanical processing as bending, cutting, milling, drilling, rolling, welding, gluing, without damaging the coating and violating the structure of the material. Under loads arising in the process of panel bending, including in the radius, there is no delamination of panels or violations of surface layers, such as cracking of aluminum sheets and paintwork. During production at the factory, the panels are protected from mechanical damage with a special film, which is removed after completion of the installation work.

Panels easily take almost any given shape, such as radius. The suitability of the material for soldering makes it possible to achieve complex geometry of products, which is impossible with any other facing material, except for aluminum, in front of which aluminum composite materials significantly win in terms of weight.

The use of aluminum composite material makes it possible to create cladding panels of various sizes and shapes, making this material indispensable in solving complex architectural problems.

- Long service life. aluminum composite materials are resistant to environmental influences such as sunlight, precipitation, wind loads, temperature fluctuations for a long time, thanks to the use of a stable coating and the combination of rigidity and elasticity achieved in the material. The estimated lifetime of the panels outdoors is about 50 years.
- Minimal care during operation. The presence of a high-quality coating contributes to the self-cleaning of the panels from external contaminants. Also, the panels are easy to clean with non-aggressive cleaners.

Two promising avenues are opened up by composite materials reinforced with either fibers or dispersed solids.

All these combined materials are combined into a system. The composite reinforcement system is used for almost all types of structures:

1. Concrete and reinforced concrete
2. Metal (including steel and aluminum)
3. Wooden
4. Brick (stone) masonry.

They also provide a range of life support needs:

1. Protection against explosions, burglary and damage.
2. Reinforcement of structures
3. Ballistic wall protection and explosion protection.
4. Protection of cables and wires from explosions

Consider the advantages and disadvantages of composite materials. Dignity:

1. Corrosion resistance
2. Tensile strength
3. Easy to use
4. Low labor cost
5. A short time implementation
6. No dimensional restrictions
7. Extremely high fatigue strength
8. Does not require conservation
9. Possibility of using constructions from different materials

Disadvantages:

1. Relative material cost
2. Limitation of scope

From the above advantages and disadvantages, we can conclude that, compared with conventional materials, composite materials have practically the only drawback - this is their rather high price. Therefore, it may be believed that this method is expensive, but if we compare the volume of consumption of steel materials for reinforcement, it is about thirty times more than composites. Other advantages of composite materials are a significant reduction in the cost of effort due to a reduction in work time, labor and mechanical equipment. Therefore, composite reinforcement systems are the main competitors to the use of steel.

However, despite the advantages over conventional materials, composite materials have their own disadvantages. These include low fire resistance, a change in properties when exposed to ultraviolet radiation, and possible cracking when the volume changes under conditions of limited freedom of deformation. The physical and mechanical properties of these materials make them susceptible to temperature fluctuations. At high temperatures, they are prone to significant creep deformations.

The role of emotions and feelings in the work of a teacher

in the process of preparing a specialist

The soul in us is formed not by the body,

And sincerity and righteousness of the deed.

The more active the soul, the younger

In fact, it looks like the sun.

Z. Brazhnikova

Today's graduate of any educational institution should be a specialist with a high intellectual culture, planetary thinking, professionally and technologically prepared for the performance of his duties. The update processes taking place in social sphere, education, production, demand from modern specialist humanistic orientation, culture, spiritual wealth, moral stability.

The relevance of this topic isthat mental and practical activity, life and life of people cannot function without the participation of emotions and feelings, as well as experiences. Summarizing the concept of “emotions”, K.D. Ushinsky characterized them as follows: “Nothing - neither words, nor thoughts, nor even our actions express ourselves so clearly, our attitudes to the world, as our feelings; one hears in them the character of not a separate thought, not a separate attitude, but the whole content of our soul, its structure” (op. vol. 9, pp. 117-118). In all its diversity, people's feelings for the surrounding reality are manifested and characterize the characteristics of each person, his attitude, morality, habits, his inner world. Emotions and feelings have a strong, even decisive influence on the excitation and inhibition of all spheres of human life. Therefore, in order to carry out his activities, a teacher must possess such qualities as professional duty, discipline, citizenship, tolerance, responsibility, etc.

The emotional state of one is the heartache or joy of the other.

The mental state of one echoes the other, and the process of communication, its dynamics (movement, change) directly depend on the mental state of the other. Nothing gives a person so much joy, delight, admiration as communication with a spiritually rich person. Just as a flower reaches out to the sun, so does a person reach out to a person if this other brings joy.

Nothing has such a strong impact on the student as the emotional state of the teacher.Imagine various situations from life:For example, if the teacher is outraged; then the student begins to resent; if one is oppressed, depressed, crying, then the other comes to the same state; if one laughs, the other does the same. Pedagogical work is a special areasocial life, which has relative independence, it performs important specific functions.

The education of feelings is the education of man in man. Without developing a sense of memory, nobility, a person destroys himself. Without feeling, ideas are cold, they shine, but do not warm, they are deprived of vitality and energy, unable to go into action. Thus, the fullness of life and the perfection of human nature lies in the organic unity of reason and feeling.

Emotions are a special class of subjective psychological states reflected in the form of direct experiences of pleasant and unpleasant processes and results practical activities aimed at meeting current needs. Any manifestations of student activity are accompanied by emotional experiences. Emotions act as internal signals. The peculiarity of emotions is that they directly reflect the relationship between motives and the implementation of activities that correspond to these motives.

Emotions are one of the most ancient mental states and processes. Emotions, Charles Darwin argued, arose in the process of evolution as a means by which living beings establish the significance of certain conditions for meeting actual needs. Emotions also perform an important mobilization, integrative- protective function. They support life process within its optimal limits and warn of the destructive nature of the lack or excess of any factors. They destroy the situation in various ways:

1) flight

2) daze

3) aggression, etc. (on the example of students of the TV-101d group)

Emotional states regulate the course of mental and organic processes. This is their regulatory function. Emotions, in fact, were the first “language” for a person, which he began to use in communicating with his own kind. Another function of emotions is obvious -communicative.

According to scientists, the "language of emotions" is quite accessible to higher animals.

Feelings are unique to humans. The most ancient in origin, the simplest and most common form of emotional experience among living beings is the pleasure derived from the satisfaction of needs and dissatisfaction. For example, the teacher enjoys the students if they are well prepared for the lesson, and the students from good grades. The main emotional states that a person experiences are divided into emotions, feelings and affects. Research scientists have shown that negative emotions reduce performance in the morning by 10% - in the evening by 64%.

Can we move away from negative emotions? Let us turn to self-analysis of the elements of emotional technique, i.e. ways to get out of a bad mood. For example, you need to set a goal: “When I have Bad mood, I go to the forest or read a book, do laundry, etc.

Similarly, one can conduct introspection using the method of an unfinished sentence: “When I am in a joyful mood, I listen to music,” etc. This technique allows everyone to get out of a negative emotion or deliver a joyful mood to themselves and others. Emotions and feelings are personal formations.

They characterize the personality socially - mentally. An emotional event can trigger the formation of new emotional relationships to different circumstances. The object of love - hatred is everything that is known by the subject as the cause of pleasure - not pleasure.

Emotions of experience and various mental states, if they are constantly tested, have a direct impact on the formation of a stable attitude to learning, on the formation of learning motivation.

At positive emotions curiosity, the need for emotional well-being are satisfied. With negative emotions, there is a departure from learning activities because none of the vital needs are met. The desired goal does not create a real perspective of the individual. And positive motivation is not formed, but motives for avoiding troubles are formed. For example, this can be observed in any educational institution: if the teacher, on the basis of emotions, expressed his attitude towards the student (for example, to a truant, to an underachiever, etc.).

AT Emotions and feelings play a socializing role in the individual development of a person. They act as a significant factor in the formation of personality, especially its motivational sphere.

On the basis of positive emotional experiences, interests and needs appear and are fixed.

Feelings are the highest cultural product - emotional development person. Feelings play a motivating role in human life, in communication. In relation to the surrounding world, a person acts in such a way as to reinforce, strengthen positive feelings. Feelings are connected with the work of consciousness. Stable feelings that act for a long time are called mood.

Feelings, emotions, emotional states are contagious. The experiences of one are involuntarily perceived by others and can lead this other to a stronger emotional state. There is a so-called model chain reaction". Students sometimes find themselves in this state., when the laughter of one "infects all." According to the “chain reaction” model, mass psychoses, panic, and applause begin.

When interacting with students huge role plays a personal example of a teacher who plays the role of an emotional mechanism. So if the teacher enters the class with a smile, then a pleasant, calm atmosphere is established in the class. And vice versa, if the teacher came in an excited state, then a corresponding emotional reaction arises among the students in the group. Affects are a reaction resulting from a committed action or deed and expressing the subjective emotional coloring of the nature of achieving the goal and meeting the needs.

One of the most common types of affects is stress. Stress is a state of being psychological stress when the nervous system gets emotional overload.

The teacher cannot be neutral to the social assessments of his behavior. Recognition, praise or condemnation of actions by others affect the well-being and self-esteem of the individual. It is they who force the individual to be especially sensitive to the attitude of others, to conform to their opinion.

Understanding the importance of feelings helps the teacher to correctly determine the line of his own behavior, as well as to influence the emotional and sensual sphere of pupils.

In the behavior of a person, feelings perform certain functions: regulatory, evaluative, prognostic, incentive.Education of feelings is a long, multifactorial process. So, emotions and feelings in the work of a teacher play a big role in the process of preparing a specialist. Based on this, the following recommendations can be made:

1. Hold back negative emotions.

2.Create optimal conditions for the development of moral feelings, in which sympathy, empathy, joy are elementary structures that form highly moral relations, in which a moral norm turns into a law, and actions into moral activity.

3. Know how to manage your feelings and emotions, and the feelings of students.

4. To implement all this, refer to the methodology of A.S. Makarenko and V.A. Sukhomlinsky “I give my heart to children”, “Pedagogical poem”, “How to raise a real person” K.D. Ushinsky, "How to win friends and influence people" by D. Carnegie, "Communication - Feelings - Fate" by K.T. Kuznechikova.

Each teacher has his own pedagogical piggy bank of rational spiritual actions, colored emotionally. May there be more seeds of the reasonable, the good, the eternal in it.