Classification of building materials Building materials are classified according to various criteria. The main types of building materials Types of building materials and their application

February 24, 2015

From the beginning of the 20th century, construction began to rapidly gain momentum. Now not only apartment buildings are being built, but also private buildings, which are located outside the city. If earlier such houses were used mainly for recreation during the holidays, now you can live in them permanently, thanks to the developed infrastructure around the main city. Actually, in order to build a private house, it is necessary to have high-quality and reliable materials in the arsenal. Now building materials are presented in a huge assortment, so it is quite easy to get confused in them.

It is foolish to simply purchase goods on the principle of "the more expensive - the better." Building materials manufacturers are constantly offering new, more advanced materials, but reality shows that you can make a really profitable purchase only in the presence of a specialist. We also note that most good stores provide delivery of building materials to any point you need, which is very convenient.

Further in the article we will talk about the main types of materials with which structures are built. Each of the types has certain features and is intended to perform specific tasks.

Types of building materials

The most common and popular materials:

  • Armature is a large set of metal parts and devices that are designed for the correct operation of a variety of equipment. Also, reinforcement is very often used to reinforce concrete, that is, to strengthen it;
  • The beam is intended mainly for overlapping interfloor ceilings. It can also be used for other purposes in the construction of structures;
  • Concrete is very widespread in all areas of construction. It has such positive characteristics as strength, durability and resistance to aggressive environments. With its help, concrete floors are made, the surface of the floor and roof is poured, various materials are created from it, for example, such as concrete fences. Also, most buildings simply cannot be built without the construction of a foundation made of concrete;
  • OSB boards are a finishing material that consists of about 90% wood chips. Bonded together with synthetic resins. Learn more about OSB boards at the link.
  • With the help of timber today, builders are building frames of light and inexpensive houses. Of the advantages of the timber, it is worth noting its environmental friendliness and ease in the construction of the building / frame;
  • Drywall is a fairly light and durable material, which is mainly used to insulate houses and create interior partitions. Drywall is very easy to mechanically process;
  • Brick is a classic material for the construction of private houses, stoves and fireplaces;
  • Steel is an unusually strong metal material that can last for many years if properly crafted;
  • Slate, roofing material and metal tiles are materials that are designed to create roofing. Each of the materials has its own advantages and service life. Buy roofing materials in Minsk on the page http://vira-tr.by/products/child/?id=2

This is not the whole list of building materials that you may need when building a private house. In conclusion, we want to say that even for the construction of the smallest building, you will need to purchase a large amount of materials, because without some, the construction will simply be impossible.

Garage doors are often used in parking lots, individual garages, as well as cottage construction. Sectional garage doors installed in a private house are becoming more and more popular due to a number of advantageous features, of which, first of all, it should be noted ease and simplicity of installation, ease of operation, as well as an attractive appearance. These gates are quiet in operation, they are reliable…


When you have a large house with several floors, you simply need forged railings. They will allow you to protect yourself and, importantly, children. Contrary to popular belief, such fences are not only highly functional, they are also quite aesthetic. If you approach the issue creatively, then you can choose a railing that will serve as a stylish addition to the interior. There are many campaigns in Kyiv,…

Currently, among the owners of country houses and cottages, modern window designs made of wood are popular. The wooden windows installed in the cottage have an aesthetic appearance, beneficially solve the problems associated with the fact that living in it is a pleasure, it is comfortable. High-quality glazing of cottages is produced by companies specializing in the production of wooden windows. Such windows are most often made according to ...

  • Natural (natural) - without changing the composition and internal structure:
    • inorganic (stone materials and products);
    • organic (wood materials, straw, fire, reeds, husks, wool, collagen).
  • Artificial:
    • Non-firing (hardening under normal conditions) and autoclave (hardening at a temperature of 175-200 ° C and a water vapor pressure of 0.9-1.6 MPa):
      • inorganic (clinker and clinker-containing cements, gypsum, magnesia, etc.);
      • organic (bituminous and dekty binders, emulsions, pastes);
      • polymeric (thermoplastic and thermoset);
      • complex:
        • mixed (mixtures of several types of mineral substances);
        • compounded (mixtures and alloys of organic materials);
        • combined (combination of mineral with organic or polymeric).
    • Roasting - hardening from fiery melts:
      • slag (according to the chemical basicity of the slag);
      • ceramic (by the nature and variety of clay and other components);
      • glass mass (in terms of charge alkalinity);
      • stone casting (by type of rock);
      • complex (according to the type of connected components, for example: ceramic slag, glass slag).

They are classified into two main categories according to their application. The first category includes - structural: brick, concrete, cement, timber, etc. They are used in the construction of various elements of buildings (walls, ceilings, coatings, floors). To the second category - special purpose: waterproofing, heat-insulating, acoustic, finishing, etc.

The main types of building materials and products

  • stone natural building materials and products from them
  • binders, inorganic and organic
  • forest materials and products from them
  • hardware

Depending on the purpose, conditions of construction and operation of buildings and structures, appropriate building materials are selected that have certain qualities and protective properties from exposure to various external environments. Given these features, any building material must have certain construction and technical properties. For example, the material for the outer walls of buildings should have the lowest thermal conductivity with sufficient strength to protect the room from the outside cold; the material of the construction for irrigation and drainage purposes - water tightness and resistance to alternating moistening and drying; road surface material (asphalt, concrete) must have sufficient strength and low abrasion to withstand traffic loads.

Properties

Materials and products must have good properties and qualities.

Property- the characteristic of the material, which manifests itself in the process of its processing, application or operation.

Quality- a set of material properties that determine its ability to meet certain requirements in accordance with its purpose.

The properties of building materials and products are classified into four main groups: physical, mechanical, chemical, technological, etc.

Chemical include the ability of materials to resist the action of a chemically aggressive environment, causing exchange reactions in them leading to the destruction of materials, a change in their original properties: solubility, corrosion resistance, resistance to decay, hardening.

Physical properties: average, bulk, true and relative density; porosity, humidity, moisture loss, thermal conductivity.

Mechanical properties: ultimate strength in compression, tension, bending, shear, elasticity, plasticity, rigidity, hardness.

Technological properties: workability, heat resistance, melting, hardening and drying speed.

Physical Properties

  1. The true density ρ is the mass of a unit volume of a material in an absolutely dense state. ρ =m/Va, where Va is the volume in the dense state. [ρ] = g/cm³; kg/m³; t/m³. For example, granite, glass and other silicates are almost completely dense materials. Determination of true density: a pre-dried sample is ground into powder, the volume is determined in a pycnometer (it is equal to the volume of the displaced liquid).
  2. The average density ρm=m/Ve is the mass per unit volume in the natural state. The average density depends on temperature and humidity: ρm=ρw/(1+W), where W is the relative humidity and ρw is the wet density.
  3. Bulk density (for bulk materials) - the mass per unit volume of loosely poured granular or fibrous materials.
  4. Porosity P - the degree of filling the volume of the material with pores. P=Vp/Ve, where Vp is the volume of pores, Ve is the volume of the material. Porosity is open and closed.

Open porosity Po - the pores communicate with the environment and among themselves, are filled with water under normal conditions of saturation (immersion in a bath of water). Open pores increase the permeability and water absorption of the material, reduce frost resistance.

Closed porosity Pz=P-Po. The increase in closed porosity increases the durability of the material, reduces sound absorption.

The porous material contains both open and closed pores.

Hydrophysical properties

  1. The water absorption of porous materials is determined according to the standard method, keeping the samples in water at a temperature of 20 ± 2 °C. At the same time, water does not penetrate into closed pores, that is, water absorption characterizes only open porosity. When removing samples from the bath, water partially flows out of large pores, so water absorption is always less than porosity. Water absorption by volume Wo (%) - the degree of filling the volume of the material with water: Wo=(mv-mc)/Ve*100, where mv is the mass of the material sample saturated with water; mc is the dry weight of the sample. Water absorption by weight Wm (%) is determined in relation to the mass of dry material Wm=(mv-mc)/mc*100. Wo=Wm*γ, γ - volumetric mass of dry material, expressed in relation to the density of water (dimensionless value). Water absorption is used to evaluate the structure of the material using the saturation coefficient: kn = Wo / P. It can vary from 0 (all pores in the material are closed) to 1 (all pores are open). A decrease in kn indicates an increase in frost resistance.
  2. Water permeability is the property of a material to let water through under pressure. Filtration coefficient kf (m/h is the dimension of speed) characterizes water permeability: kf=Vv*a/, where kf=Vv is the amount of water, m³, passing through a wall with area S = 1 m², thickness a = 1 m during time t = 1h with a difference in hydrostatic pressure at the boundaries of the wall p1 - p2 = 1 m of water. Art.
  3. The water resistance of the material is characterized by the W2 brand; W4; W8; W10; W12, denoting the one-sided hydrostatic pressure in kgf/cm² at which the concrete sample-cylinder does not pass water under the conditions of a standard test. The lower kf, the higher the water resistance mark.
  4. Water resistance is characterized by the softening coefficient kp = Rb/Rc, where Rb is the strength of the material saturated with water, and Rc is the strength of the dry material. kp varies from 0 (soaking clays) to 1 (metals). If kp is less than 0.8, then such material is not used in building structures that are in water.
  5. Hygroscopicity - the property of a capillary-porous material to absorb water vapor from the air. The process of absorption of moisture from the air is called sorption, it is due to the polymolecular adsorption of water vapor on the inner surface of the pores and capillary condensation. With an increase in water vapor pressure (that is, an increase in the relative humidity of the air at a constant temperature), the sorption moisture content of the material increases.
  6. Capillary suction is characterized by the height of the rise of water in the material, the amount of water absorbed and the intensity of suction. A decrease in these indicators reflects an improvement in the structure of the material and an increase in its frost resistance.
  7. Humidity deformations. Porous materials change their volume and size with changes in humidity. Shrinkage - reduction in the size of the material when it dries. Swelling occurs when the material is saturated with water.
Thermophysical properties
  1. Thermal conductivity is the property of a material to transfer heat from one surface to another. The Nekrasov formula relates the thermal conductivity λ [W/(m C)] to the volumetric mass of the material, expressed in relation to water: λ=1.16√(0.0196 + 0.22γ2)-0.16. As the temperature rises, the thermal conductivity of most materials increases. R - thermal resistance, R = 1/λ.
  2. Heat capacity c [kcal / (kg C)] - the amount of heat that needs to be reported to 1 kg of material in order to increase its temperature by 1 ° C. For stone materials, the heat capacity varies from 0.75 to 0.92 kJ / (kg C). With an increase in humidity, the heat capacity of materials increases.
  3. Fire resistance - the property of a material to withstand prolonged exposure to high temperatures (from 1580 ° C and above), without softening or deforming. Refractory materials are used for the internal lining of industrial furnaces. Refractory materials soften at temperatures above 1350 °C.
  4. Fire resistance - the property of a material to resist the action of fire during a fire for a certain time. It depends on the combustibility of the material, that is, on its ability to ignite and burn. Fireproof materials - concrete, brick, steel, etc. But at temperatures above 600 ° C, some fireproof materials crack (granite) or severely deform (metals). Slow-burning materials smolder under the influence of fire or high temperature, but after the fire stops, their burning and smoldering stops (asphalt concrete, wood impregnated with flame retardants, fiberboard, some foam plastics). Combustible materials burn with an open flame, they must be protected from fire by constructive and other measures, treated with flame retardants.
  5. Linear thermal expansion. With a seasonal change in the temperature of the environment and material by 50 °C, the relative temperature deformation reaches 0.5-1 mm/m. To avoid cracking, structures of great length are cut with expansion joints.

Frost resistance of building materials: the property of a water-saturated material to withstand alternate freezing and thawing. Frost resistance is quantified by the brand. The highest number of cycles of alternating freezing down to -20 °C and thawing at a temperature of 12-20 °C, which the material samples can withstand without a decrease in compressive strength of more than 15%, is taken as a brand; after testing, the samples should not have visible damage - cracks, chipping (mass loss not more than 5%).

Mechanical properties

Elasticity- spontaneous restoration of the original shape and size after the termination of the external force.

Plastic- the ability to change shape and size under the influence of external forces without collapsing, and after the termination of the action of external forces, the body cannot spontaneously restore shape and size.

Permanent deformation- plastic deformation.

Relative deformation- the ratio of absolute deformation to the initial linear size (ε=Δl/l).

Elastic modulus- the ratio of voltage to rel. strain (E=σ/ε).

Strength- the property of a material to resist destruction under the action of internal stresses caused by external forces or others. Strength is estimated by the ultimate strength - tensile strength R, determined for a given type of deformation. For fragile (brick, concrete), the main strength characteristic is the compressive strength. For metals, steel - the compressive strength is the same as in tension and bending. Since building materials are heterogeneous, the tensile strength is determined as the average result of a series of samples. The test results are influenced by the shape, dimensions of the samples, the state of the supporting surfaces, and the loading rate. Depending on the strength of the materials are divided into grades and classes. Grades are written in kgf / cm², and classes - in MPa. The class characterizes guaranteed strength. Strength class B is the tensile strength of standard specimens (concrete cubes with a rib size of 150 mm) tested at the age of 28 days of storage at a temperature of 20 ± 2 °C, taking into account the static variability of strength.

Design quality factor: KKK=R/γ(strength relative density), for 3rd steel KKK=51 MPa, for high-strength steel KKK=127 MPa, heavy concrete KKK=12.6 MPa, wood KKK=200 MPa.

Hardness- an indicator characterizing the property of materials to resist the penetration of another, denser material into it. Hardness index: HB=P/F (F is the imprint area, P is the force), [HB]=MPa. Mohs scale: talc, gypsum, lime...diamond.

Abrasion- the loss of the initial mass of the sample when this sample passes a certain path of the abrasive surface. Abrasion: And=(m1-m2)/F, where F is the area of ​​the abraded surface.

Wear- the property of a material to resist both abrasion and impact loads. Wear is determined in a drum with or without steel balls.

natural stone materials

Classification and main types of rocks

As natural stone materials in construction, rocks are used that have the necessary building properties.

According to the geological classification, rocks are divided into three types:

  1. igneous (primary)
  2. sedimentary (secondary)
  3. metamorphic (modified)

Chemical sedimentary rocks: limestone, dolomite, gypsum.

Organogenic rocks: shell limestone, diatomite, chalk.

3) Metamorphic (modified) rocks were formed from igneous and sedimentary rocks under the influence of high temperatures and pressures in the process of raising and lowering the earth's crust. These include shale, marble, quartzite.

Classification and main types of natural stone materials

Natural stone materials and products are obtained by processing rocks.

According to the method of obtaining stone materials are divided into:

  • ragged stone (but) - mined in an explosive way
  • rough-cut stone - obtained by splitting without processing
  • crushed - obtained by crushing (crushed stone, artificial sand)
  • sorted stone (cobblestone, gravel).

Stone materials are divided into

  • irregularly shaped stones (crushed stone, gravel)
  • piece products that have the correct shape (plates, blocks).

Hydration binders are divided into:

  • air (hardening and gaining strength only in air)
  • hydraulic (hardening in a humid, airy environment and under water).

Gypsum boards for partitions are made from a mixture of building gypsum with mineral or organic fillers. Plates are produced solid and hollow with a thickness of 80-100 mm. Gypsum and gypsum concrete partition slabs are used for building partitions inside the building.

Gypsum concrete panels for subfloors are made of gypsum concrete with a compressive strength of at least 7 MPa. They have a wooden rack frame. The dimensions of the panels are determined by the dimensions of the rooms. The panels are designed for linoleum floors, tiles in rooms with normal humidity.

Gypsum ventilation blocks are made from building gypsum with a compressive strength of 12-13 MPa or from a mixture of gypsum-cement-pozzolanic binder with additives. Blocks are intended for the device of ventilating channels in residential, public and industrial buildings.

Gypsum tongue-and-groove blocks are used in low-rise construction, as well as in the construction of partitions inside buildings and structures of industrial, administrative and residential areas. The lock connection of blocks in the masonry is achieved by the presence of a groove and a ridge, respectively, on each of the horizontal planes. The tongue-and-groove connection allows quick installation of a wall of tongue-and-groove blocks. In each block, two through voids are provided, which make it possible to obtain lightweight partition structures. When laying walls, the voids of all rows are combined, forming hermetic closed air cavities filled with effective insulating materials (expanded clay, mineral wool, polyurethane foam, etc.). By filling these voids with heavy concrete, any load-bearing structure can be created. Gypsum tongue-and-groove slabs are intended for element-by-element assembly of non-bearing partitions in buildings for various purposes and for internal cladding of external walls of buildings. Gypsum blocks are used in accordance with building codes and regulations for self-supporting and enclosing structures of residential, public, industrial and agricultural buildings, mainly in low-rise construction.

Due to its physical and mechanical properties, gypsum block masonry has a high airborne sound insulation index (50 dB) and thermal conductivity, which is of no small importance in the construction of both residential and industrial premises.

Artificial firing materials

Artificial firing materials and products (ceramics) are obtained by firing molded and dried clay mass at 900-1300 °C. As a result of firing, the clay mass turns into an artificial stone, which has good strength, high density, water resistance, water resistance, frost resistance and durability. The raw material for producing ceramics is clay with lean additives introduced into it in some cases. These additives reduce the shrinkage of products during drying and firing, increase porosity, and reduce the average density and thermal conductivity of the material. Sand, crushed ceramics, slag, ash, coal, sawdust are used as additives. The firing temperature depends on the temperature at which the clay starts to melt. Ceramic building materials are divided into porous and dense. Porous materials have a relative density of up to 95% and water absorption of more than 5%; their compressive strength does not exceed 35 MPa (brick, drainage pipes). Dense materials have a relative density of more than 95%, water absorption of less than 5%, compressive strength up to 100 MPa; they are durable (floor tiles).

Ceramic materials and products from fusible clays

  1. Ordinary clay bricks of plastic pressing are made from clays with or without thinning additives. The brick is a parallelepiped. Brick grades: 300, 250, 200, 150, 125, 100.
  2. Brick (stone) ceramic hollow plastic pressing is produced for laying load-bearing walls of one-story and multi-story buildings, interiors, walls and partitions, facing brick walls.
  3. Light building bricks are made by molding and firing a mass of clays with burnable additives, as well as mixtures of sand and clays with burnable additives. Brick size: 250 × 120 × 88 mm, grades 100, 75, 50, 35. Common clay bricks are used for laying internal and external walls, pillars and other parts of buildings and structures. Hollow clay and ceramic bricks are used when laying the internal and external walls of buildings and structures above the waterproofing layer. Light brick is used for laying the exterior and interior walls of buildings with normal indoor humidity.
  4. Tiles are made from fatty clay by firing at 1000-1100 °C. High-quality tiles, when lightly hit with a hammer, produce a clear, non-rattling sound. It is strong, very durable and fire resistant. Disadvantages - high average density, which makes the supporting structure of the roof heavier, fragility, the need to arrange roofs with a large slope to ensure rapid water flow.
  5. Drainage ceramic pipes are made from clays with or without lean additives, inner diameter 25-250 mm, length 333, 500, 1000 mm and wall thickness 8-24 mm. They are made in brick or special factories. Drainage ceramic pipes are used in the construction of drainage and humidification and irrigation systems, collector-drainage conduits.

Ceramic materials and products from refractory clays

  1. Stone for underground collectors is made of a trapezoidal shape with side grooves. It is used when laying underground collectors with a diameter of 1.5 and 2 m, when constructing sewer and other structures.
  2. Facade ceramic tiles are used for facing buildings and structures, panels, blocks.
  3. Ceramic sewer pipes are made from refractory and refractory clays with lean additives. They have a cylindrical shape and a length of 800, 1000 and 1200 mm, an internal diameter of 150-600 m.
  4. Floor tiles according to the type of front surface are divided into smooth, rough and embossed; by color - single-color and multi-color; in shape - square, rectangular, triangular, hexagonal, tetrahedral. Tile thickness 10 and 13 mm. It is used for flooring in the premises of industrial, water management buildings with a wet regime.
  5. Ceramic roof tiles are one of the oldest types of roofing materials that are actively used in construction today. The process of manufacturing ceramic tiles can be divided into several stages - the clay blank is first shaped, dried, coated on top, and then fired in a kiln at a temperature of about 1000 ° C.

Coagulation (organic) binders

Mortars and concretes based on them.

Organic binders used in waterproofing, in the manufacture of waterproofing materials and products, as well as waterproofing and asphalt solutions, asphalt concrete, are divided into bitumen, tar, bitumen-tar. They dissolve well in organic solvents (gasoline, kerosene), are water resistant, are able to change from a solid state to a plastic state and then liquid when heated, have high adhesion and good adhesion to building materials (concrete, brick, wood).

Anhydrite binders

Anhydrite occurs as a natural rock (CaSO4) without crystal water (natural anhydrite NAT) or is formed from artificially prepared anhydrite in flue gas sulfur recovery plants in coal fired power plants (synthetic anhydrite SYN). It is also often referred to as REA - gypsum. In order for anhydrite to take up water, basic materials such as building lime or basic and saline materials (mixed inhibitors) are added to it as excitants (inhibitors).

The anhydride solution begins to set after 25 minutes and becomes solid after no more than 12 hours. Its hardening occurs only in air. Anhydrite binder (AB) is supplied according to DIN 4208 in two strength classes. It can be used as a binder for plasters and screeds, as well as for interior building structures. Plasters with anhydrite binder must be protected from moisture.

Mixed binders

Mixed binders are hydraulic binders containing finely ground trace, blast-furnace slag or blast-furnace sand, as well as lime hydrate or Portland cement as an inhibitor for water absorption. Mixed binders harden both in air and under water. Their compressive strength is set according to DIN 4207 to at least 15 N/mm² after 28 days from laying. Mixed binders can only be used for mortars and non-reinforced concrete.

Bituminous materials

Bitumens are divided into natural and artificial. In nature, pure bitumen is rare. Usually, bitumen is extracted from mountain sedimentary porous rocks impregnated with it as a result of raising oil from the underlying layers. Artificial bitumen is obtained during oil refining, as a result of distillation of gases (propane, ethylene), gasoline, kerosene, diesel fuel from its composition.

natural bitumen- a solid or viscous liquid consisting of a mixture of hydrocarbons.

Polyethylene pipes are made by continuous screw extrusion (continuous extrusion of polymer from a nozzle with a given profile). Polyethylene pipes are frost-resistant, which allows them to be operated at temperatures from -80 °C to +60 °C.

Polymer mastics and concretes

Hydraulic structures operating in an aggressive environment, the action of high speeds and solid runoff, are protected with special coatings or linings. In order to protect structures from these effects, to increase their durability, polymer mastics, polymer concrete, polymer concrete, and polymer solutions are used.

Polymer mastics- designed to create protective coatings that protect structures and structures from the effects of mechanical stress, abrasion, temperature extremes, radiation, and aggressive environments.

Polymer concretes- cement concretes, during the preparation of which organosilicon or water-soluble polymers are added to the concrete mixture. Such concretes have increased frost resistance, water resistance.

Polymer concretes- these are concretes in which polymer resins serve as a binder, and inorganic mineral materials serve as a filler.

Polymer solutions differ from polymer concrete in that they do not contain crushed stone. They are used as waterproofing, anti-corrosion and wear-resistant coatings for hydraulic structures, floors, pipes.

Heat-insulating materials and products from them

Thermal insulation materials are characterized by low thermal conductivity and low average density due to their porous structure. They are classified according to the nature of the structure: rigid (plates, bricks), flexible (bundles, semi-rigid plates), loose (fibrous and powdery); in mind the main raw materials: organic and inorganic.

Organic thermal insulation materials

Sawdust, shavings - used in dry form, impregnated in construction with lime, gypsum, cement.

Construction felt is made from coarse wool. It is produced in the form of antiseptic-impregnated panels with a length of 1000-2000 mm, a width of 500-2000 mm and a thickness of 10-12 mm.

Reeds are produced in the form of slabs with a thickness of 30-100 mm, obtained by wire fastening through 12-15 cm rows of pressed reeds.

The construction properties of wood vary widely, depending on its age, growth conditions, wood species, and humidity. In a freshly cut tree, moisture is 35-60%, and its content depends on the time of felling and the type of tree. The lowest moisture content in the tree in winter, the highest - in the spring. The highest humidity is typical for coniferous species (50-60%), the lowest - for hard hardwoods (35-40%). Drying from the wettest state to the saturation point of the fibers (up to a moisture content of 35%), the wood does not change its dimensions; with further drying, its linear dimensions decrease. On average, shrinkage along the fibers is 0.1%, and across - 3-6%. As a result of volumetric shrinkage, gaps are formed at the junctions of wooden elements, the wood cracks. For wooden structures, wood of the moisture content at which it will work in the structure should be used.

Wood materials and products

Round wood: logs - long pieces of a tree trunk, cleared of branches; round timber (podtovarnik) - logs 3-9 m long; ridges - short segments of a tree trunk (1.3-2.6 m long); logs for piles of hydraulic structures and bridges - pieces of a tree trunk 6.5-8.5 m long. The moisture content of roundwood used for load-bearing structures should be no more than 25%.

Wood building materials are divided into lumber and board materials.

lumber

Lumber is obtained by sawing round wood.

  • Plates are logs sawn longitudinally into two symmetrical parts.
  • The beam has a thickness and width of more than 100 mm (double-edged, three-edged and four-edged).
  • Bar - lumber with a thickness of up to 100 mm and a width of no more than double the thickness.
  • Slab - the sawn off outer part of the log, in which one side is not processed.
  • Board - sawn timber with a thickness of up to 100 mm and a width of more than double the thickness. It is considered the main type of lumber.

A high-tech type of lumber is glued wall and window beams, as well as bent-glued load-bearing structures and floor beams. They are made by gluing boards, bars, plywood with waterproof adhesives. (Waterproof adhesive FBA, FOK).

Joinery products are made from lumber. Planed lengthy products are moldings (lining, floorboard, plinth, rail), platbands (window and door openings), handrails for railings, stairs, window sills, windows and doors. Joinery products are made at specialized factories or in workshops from coniferous and hardwood.

wood boards

Wood panel building materials include: plywood, fibreboard, particle board, cement particle board, oriented strand board.

For the manufacture of metal building structures and structures, rolled steel profiles are used: equal-shelf and unequal-shelf corners, channel, I-beam, and Taurus. Rivets, bolts, nuts, screws and nails are used as fasteners made of steel. When performing construction and installation works, various methods of metal processing are used: mechanical, thermal, welding. The main methods of production of metal works include mechanical hot and cold working of metals.

In hot working, metals are heated to certain temperatures, after which they are given the appropriate shapes and sizes during the rolling process, under the influence of hammer blows or press pressure.

Cold working of metals is divided into metalwork and metal cutting. Locksmith and processing consists of the following technological operations: marking, cutting, cutting, casting, drilling, cutting.

Metal processing, cutting is carried out by removing metal chips with a cutting tool (turning, planing, milling). It is produced on metal-cutting machines.

To improve the construction qualities of steel products, they are subjected to heat treatment - hardening, tempering, annealing, normalization and carburizing.

Hardening consists in heating steel products to a temperature slightly higher than the critical one, keeping them at this temperature for some time and then rapidly cooling them in water, oil, oil emulsion. The heating temperature during hardening depends on the carbon content in the steel. Hardening increases the strength and hardness of steel.

Tempering consists in heating hardened products to 150-670 ° C (tempering temperature), curing them at this temperature (depending on the steel grade) and subsequent slow or rapid cooling in still air, water or in oil. In the process of tempering, the viscosity of steel increases, the internal stress in it and its brittleness decrease, and its machinability improves.

Annealing consists in heating steel products to a certain temperature (750-960 ° C), holding them at this temperature and then slowly cooling them in a furnace. When annealing steel products, the hardness of steel decreases, and its machinability also improves.

Normalization - consists in heating steel products to a temperature slightly higher than the annealing temperature, holding them at this temperature and then cooling them in calm air. After normalization, steel with higher hardness and fine grain structure is obtained.

Carburizing is a process of surface carburization of steel in order to obtain high surface hardness, wear resistance and increased strength from products; while the inner part of the steel retains a significant toughness.

Non-ferrous metals and alloys

These include: aluminum and its alloys are light, technological, corrosion-resistant material. In its pure form, it is used for the manufacture of foil, casting parts. For the manufacture of aluminum products, aluminum alloys are used - aluminum-manganese, aluminum-magnesium ... Aluminum alloys used in construction at a low density (2.7-2.9 g / cm³) have strength characteristics that are close to the strength characteristics of building steels. Products made of aluminum alloys are characterized by simplicity of manufacturing technology, good appearance, fire and seismic resistance, anti-magnetic properties, and durability. This combination of construction and technological properties of aluminum alloys allows them to compete with steel. The use of aluminum alloys in the enclosing structures makes it possible to reduce the weight of walls and roofs by 10-80 times, and to reduce the laboriousness of installation.

Copper and its alloys. Copper is a heavy non-ferrous metal (density 8.9 g/cm³), soft and ductile with high thermal and electrical conductivity. In its pure form, copper is used in electrical wires. Copper is mainly used in alloys of various types. An alloy of copper with tin, aluminum, manganese or nickel is called bronze. Bronze is a corrosion-resistant metal with high mechanical properties. It is used for the manufacture of sanitary fittings. An alloy of copper and zinc (up to 40%) is called brass. It has high mechanical properties and corrosion resistance, lends itself well to hot and cold processing. It is used in the form of products, sheets, wire, pipes.

Zinc is a corrosion-resistant metal used as an anti-corrosion coating when galvanizing steel products in the form of roofing steel, bolts.

Lead is a heavy, easy-to-work, corrosion-resistant metal used for caulking seams in socket pipes, sealing expansion joints, and manufacturing special pipes.

Metal corrosion and protection against it

The impact on metal structures and structures of the environment leads to their destruction, which is called corrosion. Corrosion begins from the surface of the metal and spreads deep into it, while the metal loses its luster, its surface becomes uneven, corroded.

According to the nature of corrosion damage, continuous, selective and intergranular corrosion are distinguished.

Continuous corrosion is divided into uniform and uneven. With uniform corrosion, the destruction of the metal proceeds at the same rate over the entire surface. With uneven corrosion, the destruction of the metal proceeds at an unequal rate in different parts of its surface.

Selective corrosion covers certain areas of the metal surface. It is subdivided into surface, point, through, and spot corrosion.

Intergranular corrosion manifests itself inside the metal, while bonds along the boundaries of the crystals that make up the metal are destroyed.

According to the nature of the interaction of the metal with the environment, chemical and electrochemical corrosion are distinguished. Chemical corrosion occurs when metal is exposed to dry gases or non-electrolyte liquids (gasoline, oil, resins). Electrochemical corrosion is accompanied by the appearance of an electric current that occurs when liquid electrolytes (aqueous solutions of salts, acids, alkalis), moist gases and air (conductors of electricity) act on the metal.

To protect metals from corrosion, various methods of their protection are used: sealing metals from an aggressive environment, reducing environmental pollution, ensuring normal temperature and humidity conditions, and applying durable anti-corrosion coatings. Usually, in order to protect metals from corrosion, they are coated with paints and varnishes (primers, paints, enamels, varnishes), protected with corrosion-resistant thin metal coatings - they are used to construct walls, foundations, floors, roofs and other parts of residential and non-residential buildings and structures. S. m. are usually divided into natural ones, which are used for construction in the form in which they are in nature (wood, granite, ... ... Big Medical Encyclopedia


    • The category of general building materials includes a list of indispensable products that are widely used in various construction industries. They are used in the construction of new facilities and the reconstruction of existing ones, therefore they are extremely in demand. General construction materials are the basic basis of any construction, therefore, they are subject to the highest requirements regarding strength, reliability, and service life.

    • reinforced concrete products;
    • bricks;
    • blocks;
    • loose and bulk substances.

    The first group - concrete goods. Reinforced concrete products are structures manufactured in the factory by injection molding with subsequent hardening. This method of production allows you to control the quality of products and carry out a number of tests of the material for compliance with regulatory requirements. This group includes slabs, piles, curbstones, foundation blocks and many other products. They are used at all stages of construction

    The next category is bricks. Products are artificial stones of the correct form, made of mineral materials (clay, silicate compositions, adobe and others). Used as the main material for the construction of facilities. As for the blocks, they are used for the construction of external enclosing structures for residential, public, industrial and agricultural facilities with a normal temperature and humidity regime of the internal space. They can be made of aerated concrete, lime-sand mixture and other composite materials.

    The last group - bulk substances. These include sand, expanded clay, gravel and many others. They differ in fraction (granule size), density and strength. They are used for various purposes - as a filler for compositions and mixtures, a heat-insulating layer, as well as bulk material for arranging a pillow.

    The reliability and durability of the structure depends on their quality. Therefore, if necessary, it is necessary to contact companies that offer only certified products.

    K category: Construction materials

    Classification of building materials

    Building materials are divided into natural (natural) and artificial. The first group includes: forest (roundwood, lumber); stone dense and loose rocks (natural stone, gravel, sand, clay), etc. The second group - artificial materials - includes: binders (cement, lime), artificial stones (brick, blocks); concretes; solutions; metal, heat and waterproofing materials; ceramic tiles; synthetic paints, varnishes and Other materials, the production of which is associated with chemical processing.

    Building materials are classified according to their purpose and scope, for example, roofing materials - roofing material, asbestos cement, etc.; wall - brick, blocks; finishing - solutions, paints, varnishes; facing, waterproofing, etc., as well as according to the technological basis of their manufacture, for example, ceramic, synthetic, etc. A special group is made up of heat-insulating building materials - they are made from various raw materials, used in various designs, but they are combined by a common property - low bulk density and low thermal conductivity, which determines the constantly increasing volume of their production and widespread use in construction.

    Building materials that are mined or manufactured in the area of ​​the facility under construction are commonly referred to as local building materials. These primarily include: sand, gravel, crushed stone, brick, lime, etc. In the construction of buildings and structures, it is necessary first of all to use local building materials, which reduces transportation costs, which make up a significant part of the cost of materials.

    For building materials manufactured by enterprises, there are State All-Union Standards - GOSTs and technical conditions - TU. The standards provide basic information about the building material, give its definition, indicate raw materials, applications, classification, division into grades and brands, test methods, transportation and storage conditions. GOST has the force of law, and compliance with it is mandatory for all enterprises manufacturing building materials.

    The nomenclature and technical requirements for building materials and parts, their quality, guidelines for the selection and use, depending on the operating conditions of the building or structure being erected, are set out in the "Building Norms and Rules" - SNiP I-B.2-69, approved by the USSR State Construction Committee in 1962-1969 gg. as amended in 1972. State All-Union Standards (GOSTs) have been developed for each material and product.

    For the correct use of a particular material in construction, it is necessary to know the physical, including the ratio of materials to the action of water and temperatures, and mechanical properties.

    Residential, public and industrial buildings are structures designed to accommodate people and various equipment and protect them from environmental influences. All buildings consist of parts of the same purpose: - the foundation, which serves as the foundation of the building and transfers the load from the entire building to the ground; - frame - the supporting structure on which the enclosing elements of the building are installed; the frame perceives and redistributes loads and transfers them to the foundation; - enclosing structures that isolate the internal volume of the building from the effects of the external environment or separating individual parts of the internal volume from each other; Enclosing structures include walls, floors and roofs, and in low-rise buildings, walls and floors often serve as a frame.

    From ancient times, residential and religious buildings were built from natural materials - stone and wood, and all parts of the building were made from them: the foundation, walls, roof. This versatility of the material had significant drawbacks. The construction of stone buildings was labor intensive; to maintain a normal thermal regime in the building, stone walls had to be made very thick (up to 1 m or more), since natural stone is a good conductor of heat. For the construction of ceilings and roofs, many columns were placed or heavy stone vaults were made, since the strength of the stone is not enough to cover large spans. Stone buildings, however, had one positive quality - durability. Less labor-intensive but short-lived wooden buildings were often destroyed by fire.

    With the development of industry, new, different-purpose building materials appeared: for roofing - sheet iron, later - rolled materials and asbestos cement; for load-bearing structures - rolled steel and high-strength concrete; for thermal insulation - fibrolite, mineral wool, etc.

    Specialization and industrial production of building materials, semi-finished products and products radically changed the nature of construction. Materials, and then products made from them, began to arrive at the construction site practically in finished form, building structures became lighter and more efficient (for example, they were better protected from heat loss, from moisture, etc.). At the beginning of the XX century. factory production of building structures (metal trusses, reinforced concrete columns) began, but only since the 50s, for the first time in the world in our country, began to build prefabricated buildings from prefabricated elements.

    The modern industry of building materials and products produces a large number of finished building parts and materials for various purposes, for example: ceramic tiles for floors, for interior cladding, facade, carpet mosaics; roofing material and glassine for roofing, insulating and hydro-insulating - for waterproofing. To make it easier to navigate in this variety of building materials and products, they are classified. The most widely used classifications are by purpose and technological feature.

    By purpose, materials are divided into the following groups: - structural, which perceive and transmit loads in building structures; - heat-insulating, the main purpose of which is to minimize the transfer of heat through the building structure and thereby ensure the necessary thermal regime of the room with minimal energy consumption; - acoustic (sound-absorbing and soundproof) - to reduce the level of "noise pollution" of the room; - waterproofing and roofing - to create waterproof layers on roofs, underground structures and other structures that need to be protected from water or water vapor; - sealing - for sealing joints in prefabricated structures; - finishing - to improve the decorative qualities of building structures, as well as to protect structural, heat-insulating and other materials from external influences; - special purpose (for example, refractory or acid-resistant), used in the construction of special structures.

    A number of materials (for example, cement, lime, wood) cannot be attributed to any one group, since they are used both in their pure form and as raw materials for the production of other building materials and products - these are the so-called general-purpose materials. The difficulty of classifying building materials by purpose is that the same materials can be assigned to different groups. For example, concrete is mainly used as a structural material, but some of its types have a completely different purpose: especially lightweight concrete - heat-insulating materials; especially heavy concretes are special-purpose materials used for protection against radioactive radiation.

    The basis of the classification according to technological features is the type of raw material from which the material is obtained, and the method of manufacture. These two factors largely determine the properties of the material and, accordingly, the scope of its application. According to the manufacturing method, materials obtained by sintering (ceramics, cement), melting (glass, metals), monolithic with binders (concrete, mortar) and mechanical processing of natural raw materials (natural stone, wood materials) are distinguished. For a deeper understanding of the properties of materials, which depend mainly on the type of raw material and the method of its processing, the course "Materials Science" is based on a classification according to a technological feature, and only in some cases are considered groups of materials according to their purpose.



    - Classification of building materials

    Questions:

    1) The main types of building materials;

    2) Advantages and disadvantages of structures made of reinforced concrete, stone, steel, wood;

    The main types of building materials are: reinforced concrete, steel, stone (artificial and natural), wood. Artificial stones include ceramic and silicate bricks, as well as concrete, slag concrete, foam concrete, aerated concrete, polystyrene concrete, ceramic and other blocks. Natural stones include blocks of tuff, shell rock, limestone, buta, etc. Aluminum, duralumin, polymers, bitumen and tar are also used for the manufacture of building structures.

    The variety of materials and structures used in construction is determined by the large number of requirements imposed on them (strength, deformation, heat engineering, fire protection, acoustic, economic, aesthetic, etc.). There is no ideal building material that meets all these requirements.

    Structures made of different materials have their own advantages and disadvantages.

    Concrete structures were known before our era. However, a real breakthrough in construction was the invention of reinforced concrete in the middle of the century before last. Although reinforced concrete structures began to be widely used in the 1950s. Concrete is a composite material made using aggregates (gravel, crushed stone, sand) and a binder (adhesive composition). Reinforced concrete is a material consisting of concrete and reinforcement. The term reinforced concrete is traditional, but not entirely correct. The fact is that iron used to be called steel, which is now used for reinforcement. Concrete structures are not widely used due to its serious drawback. Concrete performs well in compression, but poorly in tension. Steel, on the contrary, works well in tension, and loses stability at high compressive stresses. Therefore, the main principle of designing reinforced concrete structures is the installation of reinforcement in zones stretched during operation, manufacture, transportation and installation. The essence of obtaining such a highly effective material lies in a number of factors:


    1) steel and concrete have approximately the same coefficients of thermal expansion;

    2) concrete is resistant to many aggressive influences and perfectly protects steel from them;

    3) concrete has a high heat capacity, which protects the reinforcement during emergency temperature effects (fires);

    4) concrete and reinforcement mutually compensate for each other's shortcomings under force effects (tensile and compression).

    Reinforced concrete structures have the following advantages:

    1) strength, especially in compression and bending;

    2) rigidity;

    3) durability;

    4) fire resistance and fire resistance;

    5) resistance to aggressive influences;

    6) the ability to be made in any shape;

    7) industrialism.

    Despite all the advantages, reinforced concrete has a number of disadvantages. Concrete has a high thermal conductivity. It is problematic to make building envelopes from reinforced concrete. There are ways to increase the heat-insulating ability of concrete: the manufacture of air voids (hollow blocks), increasing porosity (foam and aerated concrete), the introduction of heat-insulating materials (polystyrene, slag, expanded clay concrete, etc.). All these methods lead to a change for the worse in the strength and deformation properties of manufactured products and structures.

    Reinforced concrete structures are heavy. In this regard, their use in high-rise and large-span structures is difficult.

    Reinforced concrete is a porous material with open and closed pores. This contributes to its water and breathability. It is possible to make tanks and pipelines for some liquids from reinforced concrete, but it is impossible to make gas holders.

    Prefabricated reinforced concrete structures require additional steel consumption for embedded parts for their connection. In addition, they often require additional reinforcement due to the peculiarities of transportation and installation. However, prefabricated structures are highly industrial and require less time for manufacture and installation, which reduces construction time.

    stone structures by the nature of work under load and by properties similar to concrete. Stone is one of the ancient building materials. Stone materials work well in compression and poorly in tension. They are resistant to aggressive influences, fire-resistant, fire-resistant, durable. However, such designs have several disadvantages:

    1) it is difficult to make bendable structures from stone and it is almost impossible to make stretched ones;

    2) they cannot take a variety of forms;

    3) they have low industrialization, which leads to an increase in construction time;

    4) they have a high thermal conductivity, which leads to an overrun of the material;

    5) they are heavy.

    3) high operating costs.

    Wooden structures without special measures have low durability. In addition, one should be aware of the weak reproducibility of this resource.

    In the oil and gas industry, wooden structures are used for temporary buildings, as well as for the production of temporary retaining walls in

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