Building structures, load-bearing and enclosing structures of buildings and structures.

Classification and areas of application. Division of building structures by functional purpose on load-bearing and enclosing ones is largely conditional. If structures such as arches, trusses or frames are only load-bearing, then wall and roof panels, shells, vaults, folds, etc. usually combine enclosing and load-bearing functions, which corresponds to one of the most important trends in the development of modern building structures. Depending on the design scheme, load-bearing building structures are divided into flat (for example, beams, trusses, frames) and spatial (shells, vaults, domes, etc. .). Spatial structures are characterized by more favorable (compared to flat) distribution of forces and, accordingly, lower consumption of materials; however, their production and installation in many cases turn out to be very labor-intensive. New types of spatial structures, for example, structural structures made from rolled profiles with bolted connections, are distinguished by both cost-effectiveness and comparative ease of manufacture and installation. Based on the type of material, the following main types of building structures are distinguished: concrete and reinforced concrete.

Concrete and reinforced concrete structures are the most common (both in terms of volume and areas of application). Special types of concrete and reinforced concrete are used in the construction of structures operated at high and low temperatures or in chemically aggressive environments (thermal units, buildings and structures of ferrous and non-ferrous metallurgy, chemical industry and etc.). Reducing weight, reducing cost and consumption of materials in reinforced concrete structures are possible through the use of high-strength concrete and reinforcement, increased production of prestressed structures, and expansion of the areas of application of lightweight and cellular concrete.

Steel structures are used mainly for the frames of long-span buildings and structures, for workshops with heavy crane equipment, blast furnaces, large-capacity tanks, bridges, tower-type structures, etc. The areas of application of steel and reinforced concrete structures in some cases coincide. A significant advantage of steel structures (compared to reinforced concrete) is their lighter weight.

Requirements for building structures. From the point of view of operational requirements, S.K. must meet its purpose, be fire-resistant and corrosion-resistant, safe, convenient and economical to operate.

Calculation S.K. Building structures must be designed for strength, stability and vibrations. This takes into account the force impacts that structures are subjected to during operation (external loads, dead weight), the influence of temperature, shrinkage, displacement of supports, etc. as well as the forces arising during transportation and installation of building structures.

Foundations of buildings and structures are parts of buildings and structures (mainly underground) that serve to transfer loads from buildings (structures) to a natural or artificial foundation. A building wall is the main enclosing structure of a building. Along with enclosing functions, walls simultaneously, to one degree or another, also perform load-bearing functions (they serve as supports for absorbing vertical and horizontal loads.

Frame (French carcasse, from Italian carcassa) in technology is the skeleton (skeleton) of any product, structural element, entire building or structure, consisting of individual rods fastened together. The frame is made of wood, metal, reinforced concrete and other materials. It determines the strength, stability, durability, and shape of a product or structure. Strength and stability are ensured by rigid fastening of rods at mating or hinge joints and special stiffening elements that give the product or structure a geometrically unchangeable shape. An increase in the rigidity of the frame is often achieved by incorporating the shell, cladding or walls of the product or structure into the work.

Floors are horizontal load-bearing and enclosing structures. They perceive vertical and horizontal force impacts and transmit them to load-bearing walls or frames. Ceilings provide heat and sound insulation of rooms.

Floors in residential and public buildings must meet the requirements of strength and wear resistance, sufficient elasticity and noiselessness, and ease of cleaning. The design of the floor depends on the purpose and nature of the premises where it is installed.

The roof is the external load-bearing and enclosing structure of the building, which absorbs vertical (including snow) and horizontal loads and impacts. (Wind is a load.

Stairs in buildings serve to vertically connect rooms located at different levels. The location, number of stairs in the building and their sizes depend on the adopted architectural and planning solution, number of storeys, intensity of human flow, as well as fire safety requirements.

Windows are arranged for lighting and ventilation (ventilation) of rooms and consist of window openings, frames or frames and filling the openings, called window sashes.

Question No. 12. Behavior of buildings and structures in fire conditions, their fire resistance and fire hazard.

The loads and impacts to which a building is exposed under normal operating conditions are taken into account when calculating the strength of building structures. However, during fires, additional loads and impacts arise, which in many cases lead to the destruction of individual structures and buildings as a whole. Unfavorable factors include: high temperature, pressure of gases and combustion products, dynamic loads from falling debris from collapsed building elements and spilled water, sudden temperature fluctuations. The ability of a structure to maintain its functions (load-bearing, enclosing) in fire conditions and to resist the effects of fire is called the fire resistance of a building structure.

Building structures are characterized by fire resistance and fire hazard.

An indicator of fire resistance is the fire resistance limit; the fire hazard of a structure is characterized by its fire hazard class.

Building structures of buildings, structures and structures, depending on their ability to resist the effects of fire and its spread hazardous factors under standard test conditions, they are divided into building structures with the following fire resistance limits.

- not standardized; - at least 15 minutes; - at least 30 minutes; - at least 45 minutes; - at least 60 minutes; - at least 90 minutes; - at least 120 minutes; - at least 180 minutes; - at least 360 minutes .

The fire resistance limit of building structures is established by the time (in minutes) of the onset of one or sequentially several, normalized for a given structure, signs of limit states: loss of load-bearing capacity (R); loss of integrity (E); loss of thermal insulation capacity (I.

Fire resistance limits of building structures and their symbols are established in accordance with GOST 30247. In this case, the fire resistance limit of windows is established only according to the time of loss of integrity (E.

Based on fire hazard, building structures are divided into four classes: KO (non-fire hazardous); K1 (low fire hazard); K2 (moderate fire hazard); KZ (fire hazard.

Question No. 13. Metal structures and their behavior in fire conditions, ways to increase the fire resistance of structures.

Although metal structures are made of fireproof material, their actual fire resistance limit is on average 15 minutes. This is explained by a fairly rapid decrease in the strength and deformation characteristics of the metal at elevated temperatures during a fire. MK heating intensity ( metal structure) depends on a number of factors, which include the nature of heating of structures and methods of protecting them. In the case of a short-term effect of temperature during a real fire, after the ignition of combustible materials, the metal is heated more slowly and less intensely than the heating of the environment. When the “standard” fire mode is in effect, the ambient temperature does not cease to rise and the thermal inertia of the metal, causing a certain heating delay, is observed only during the first minutes of the fire. Then the temperature of the metal approaches the temperature of the heating medium. The protection of the metal element and the effectiveness of this protection also affects the heating of the metal.

When acting on a beam high temperatures In the event of a fire, the cross section of the structure quickly warms up to the same temperature. This reduces the yield strength and elastic modulus. The collapse of rolled beams is observed in the section where the maximum bending moment acts.

The impact of fire temperature on a farm leads to the depletion of the load-bearing capacity of its elements and the node connections of these elements. The loss of load-bearing capacity as a result of a decrease in the strength of the metal is typical for stretched and compressed elements of the chords and lattice of the structure.

Exhaustion of the load-bearing capacity of steel columns exposed to fire conditions can occur as a result of loss of: strength of the structural core; strength or stability of the elements of the connecting lattice, as well as the attachment points of these elements to the branches of the column; stability of individual branches in the areas between the nodes of the connecting lattice; general stability of the column.

The behavior of arches and frames in fire conditions depends on the static operating diagram of the structure, as well as the cross-sectional design of these elements.

Methods for increasing fire resistance.

· cladding made of non-combustible materials (concreting, brick cladding, heat-insulating boards, plasterboard sheets, plaster.

· fire-retardant coatings (non-intumescent and intumescent coatings.

· suspended ceilings (an air gap is created between the structure and the ceiling, which increases its fire resistance limit.

Limit state of a metal structure: =R n * tem.

— 2015-2017 year. (0.008 sec.

Folds, etc. usually combine enclosing and load-bearing functions, which corresponds to one of the most important trends in the development of modern Building construction Depending on the design scheme carriers Building construction divided into flat (for example, beams, trusses, frames) and spatial (shells, vaults, domes and so on.). Spatial structures are characterized by more favorable (compared to flat) distribution of forces and, accordingly, lower consumption of materials; however, their production and installation in many cases turn out to be very labor-intensive. New types of spatial structures, for example the so-called. Structural structures made from rolled profiles with bolted connections are distinguished by both cost-effectiveness and comparative ease of manufacture and installation. Based on the type of material, the following main types are distinguished: Building construction: concrete and reinforced concrete (see. Reinforced concrete structures and products ), steel structures, stone structures, wooden structures.

Concrete and reinforced concrete structures are the most common (both in terms of volume and areas of application). Modern construction is particularly characterized by the use of reinforced concrete in the form of prefabricated industrial structures used in the construction of residential, public and industrial buildings and many engineering structures. Rational areas of application of monolithic reinforced concrete are hydraulic structures, road and airfield pavements, foundations for industrial equipment, tanks, towers, elevators, etc. Special types concrete and reinforced concrete are used in the construction of structures operated at high and low temperatures or in chemically aggressive environments (thermal units, buildings and structures of ferrous and non-ferrous metallurgy, chemical industry, etc.). Reducing weight, reducing cost and consumption of materials in reinforced concrete structures are possible through the use of high-strength concrete and reinforcement and increased production prestressed structures, expanding the areas of application of lightweight and cellular concrete.

Steel structures are used mainly for the frames of long-span buildings and structures, for workshops with heavy crane equipment, blast furnaces, large-capacity tanks, bridges, tower-type structures, etc. The areas of application of steel and reinforced concrete structures in some cases coincide. In this case, the choice of the type of structures is made taking into account the ratio of their costs, as well as depending on the construction area and the location of construction industry enterprises. A significant advantage of steel structures (compared to reinforced concrete) is their lighter weight. This determines the feasibility of their use in areas with high seismicity, hard-to-reach areas of the Far North, desert and high mountain areas, etc. Expanding the use of high-strength steels and economical rolled profiles, as well as the creation of efficient spatial structures (including thin-sheet steel) will significantly reduce the weight of buildings and structures.

The main area of ​​application of stone structures is walls and partitions. Brick buildings, natural stone, small blocks, etc. meet the requirements of industrial construction to a lesser extent than large-panel buildings (see article Large panel structures ). Therefore, their share in the total volume of construction is gradually decreasing. However, the use of high-strength bricks, reinforced stone, etc. complex structures (stone structures reinforced with steel reinforcement or reinforced concrete elements) can significantly increase the load-bearing capacity of buildings with stone walls, and the transition from manual masonry to the use of factory-made brick and ceramic panels can significantly increase the degree of industrialization of construction and reduce the labor intensity of constructing buildings from stone materials .

The main direction in the development of modern wooden structures is the transition to structures made of laminated wood. Possibility of industrial manufacturing and production of structural elements required sizes through gluing determines their advantages compared to wooden structures of other types. Load-bearing and enclosing glued structures are widely used in agriculture. construction.

IN modern construction New types of industrial structures are becoming widespread - asbestos-cement products and structures, pneumatic building structures, structures made of light alloys and using plastics. Their main advantages are low specific gravity and the possibility of factory production on mechanized production lines. Lightweight three-layer panels (with skins made of profiled steel, aluminum, asbestos-cement and plastic insulation) are beginning to be used as enclosing structures instead of heavy reinforced concrete and expanded clay concrete panels.

Requirements for Building construction WITH in terms of operational requirements Building construction must meet its intended purpose, be fire-resistant and corrosion-resistant, safe, convenient and economical to operate. The scale and pace of mass construction place demands on Building construction requirements for the industrial nature of their production (in factory conditions), efficiency (both in cost and in terms of material consumption), ease of transportation and speed of installation at a construction site. Of particular importance is the reduction of labor intensity - both in manufacturing Building construction, and in the process of erecting buildings and structures from them. One of the most important tasks of modern construction is weight reduction Building construction based on the widespread use of lightweight, effective materials and improvement constructive solutions.

Calculation s. To. Building structures must be designed for strength, stability and vibration. This takes into account the forces to which structures are subjected during operation (external loads, dead weight), the influence of temperature, shrinkage, displacement of supports, etc., as well as the forces arising during transportation and installation Building construction In the USSR the main method of calculation Building construction is the calculation method according to limit states, approved by the USSR State Construction Committee for mandatory use from January 1, 1955. Before that Building construction calculated depending on the materials used by permissible stresses (metal and wood) or by destructive forces (concrete, reinforced concrete, stone and reinforced stone). Main disadvantage These methods included the use in calculations of a single (for all existing loads) safety factor, which did not allow one to correctly assess the magnitude of variability of loads of different natures (constant, temporary, snow, wind, etc.) and the maximum load-bearing capacity of structures. In addition, the calculation method based on permissible stresses did not take into account the plastic stage of the structure’s operation, which led to an unjustified waste of materials.

When designing a particular building (structure), the optimal types Building construction and the materials for them are selected in accordance with the specific conditions of construction and operation of the building, taking into account the need to use local materials and reduce transport costs. When designing mass construction projects, as a rule, standard Building construction and unified dimensional diagrams of structures.

Lit.: Baikov V.N., Strongin S.G., Ermolova D.I., Building structures, M., 1970; Building codes and regulations, part 2, section A, ch. 10. Building structures and foundations, M., 1972: Building structures, ed. A. M. Ovechkin and R. L. Mailyan. 2nd ed., M., 1974.

G. Sh. Podolsky

Article about the word " Building construction" in the Great Soviet Encyclopedia was read 27210 times

Introduction

Building load-bearing structures of industrial and civil buildings and engineering structures are structures whose cross-sectional dimensions are determined by calculation. This is their main difference from architectural structures or parts of buildings, the section sizes of which are assigned according to architectural, thermal engineering or other special requirements.

Modern building structures must satisfy the following requirements: operational, environmental, technical, economic, production, aesthetic, etc.

Classification of building structures

Concrete and reinforced concrete structures are the most common (both in volume and in areas of application). Modern construction is especially characterized by the use of reinforced concrete in the form of prefabricated industrial structures used in the construction of residential, public and industrial buildings and many engineering structures. Rational areas of application of monolithic reinforced concrete are hydraulic structures, road and airfield pavements, foundations for industrial equipment, tanks, towers, elevators, etc. Special types of concrete and reinforced concrete are used in the construction of structures operated at high and low temperatures or in chemically aggressive environments (thermal units, buildings and structures of ferrous and non-ferrous metallurgy, chemical industry, etc.). Reducing weight, reducing cost and consumption of materials in reinforced concrete structures are possible through the use of high-strength concrete and reinforcement, increased production of prestressed structures, and expansion of the areas of application of lightweight and cellular concrete.

Steel structures are used mainly for the frames of long-span buildings and structures, for workshops with heavy crane equipment, blast furnaces, large-capacity tanks, bridges, tower-type structures, etc. The areas of application of steel and reinforced concrete structures in some cases coincide. In this case, the choice of the type of structures is made taking into account the ratio of their costs, as well as depending on the construction area and the location of construction industry enterprises. A significant advantage of steel structures (compared to reinforced concrete) is their lighter weight. This determines the feasibility of their use in areas with high seismicity, hard-to-reach areas of the Far North, desert and high mountain areas, etc. Expanding the use of high-strength steels and economical rolled profiles, as well as the creation of efficient spatial structures (including thin-sheet steel) will significantly reduce the weight of buildings and structures.

The main area of ​​application of stone structures is walls and partitions. Buildings made of brick, natural stone, small blocks, etc. meet the requirements of industrial construction to a lesser extent than large-panel ones. Therefore, their share in the total volume of construction is gradually decreasing. However, the use of high-strength bricks, reinforced stone, etc. complex structures (stone structures reinforced with steel reinforcement or reinforced concrete elements) can significantly increase the load-bearing capacity of buildings with stone walls, and the transition from manual masonry to the use of factory-made brick and ceramic panels can significantly increase the degree of industrialization of construction and reduce the labor intensity of constructing buildings made of stone materials.

The main direction in the development of modern wooden structures is the transition to structures made of laminated wood. The possibility of industrial manufacturing and obtaining structural elements of the required dimensions by gluing determines their advantages compared to other types of wooden structures. Load-bearing and enclosing glued structures are widely used in agriculture. construction.

In modern construction, new types of industrial structures are becoming widespread - asbestos-cement products and structures, pneumatic building structures, structures made of light alloys and using plastics. Their main advantages are low specific gravity and the possibility of factory production on mechanized production lines. Lightweight three-layer panels (with skins made of profiled steel, aluminum, asbestos-cement and plastic insulation) are beginning to be used as enclosing structures instead of heavy reinforced concrete and expanded clay concrete panels.

All building structures are divided into carriers And non-load-bearing(mostly - fencing). In some cases, the functions of load-bearing and enclosing structures are combined (for example, external load-bearing walls, attic floors, etc.).

According to the nature of static work, load-bearing structures are divided into planar And spatial. In planar systems, all elements work either separately or in the form of rigidly interconnected flat systems (core elements - posts, beams, walls, floor slabs). In spatial ones, all elements work in two directions. This increases the rigidity and load-bearing capacity of structures and reduces the consumption of materials for their construction.

The main structural elements of civil buildings are foundations, steps and pillars, floors, roofs, stairs, windows, doors and partitions (Fig. 13.1).

Rice. 13.1. Basic elements of civil buildings(A – old building;b – frame-panel modern;V - from volumetric blocks):

1 – foundation; 2 – base; 3 – load-bearing longitudinal walls; 4 – interfloor ceilings; 5 – partitions; 6 – roof rafters; 7 – roof; 8 – staircase; 9 – attic floor; 10 – crossbars and columns of the frame; 11 – curtain wall panels; 12 – piles; 13–13 – volumetric blocks (13 – rooms; 14 – bathrooms and kitchens; 15 – staircase); 16 – blind area

Foundations serve to transfer loads from the building’s own weight, from people and equipment, from snow and wind to the ground. They are underground structures and are located under load-bearing walls and pillars. The soil is the basis for foundations. The base must be strong and low-compressible when loaded. The top layers of soil are usually not strong enough. Therefore, the base of the foundation is placed (laid) at a certain depth from the surface of the earth. The depth of the foundation is determined not only by the strength of the soil, but also by its composition and climatic features terrain. So, in clayey, loamy sandy soils and fine sands, the depth of the foundation should be below the depth of soil freezing. This depth is given in SNiP 29-99 "Building climatology". In heated buildings

the foundation depth can be reduced depending on thermal regime in the building (central or stove heating, calculated internal temperatures), since a heated building warms up the soil underneath and the freezing depth decreases. The above types of soil are susceptible to heaving. Water accumulating under the base of the foundation freezes and increases in volume. This leads to uneven bulging of the soil and the appearance of cracks in foundations and walls.

In buildings with a basement, the depth of the foundation depends on the height of the basement.

The base of the foundation must have such an area that the load transmitted to the soil does not exceed the stress allowed for this soil, which is usually 1–3 kg/cm2. Foundations are usually made of waterproof material (concrete blocks, monolithic reinforced concrete). In historical buildings, the foundations were usually made of natural stone (rubble) or rubble concrete. Brick was practically not used, with the exception of very well-burnt so-called engineering brick, which practically did not absorb water.

The main types of foundations are the following: strip, columnar, pile and in the form of a monolithic reinforced concrete slab covering the entire building.

Tape foundations are divided into prefabricated and monolithic. Monolithic ones are made from rubble stone masonry.

They are labor-intensive to manufacture and are currently used for low-rise construction only where rubble stone is local building material. It is more rational to make foundations from monolithic concrete using inventory panel formwork. Strip foundations made of prefabricated reinforced concrete blocks are the most rational solution if there is production of such blocks and crane equipment for their installation in the construction area.

The designs of strip foundations are shown in Fig. 13.2.

Rice. 13.2.

A - on a sand cushion; b – rubble concrete foundation of a low-rise building; V – rubble foundation of a low-rise building; G - rubble foundation with ledges; d – rubble foundation of a building with a basement; e – rubble concrete foundation of a house with a basement; and - prefabricated foundation of a low-rise building; h – prefabricated foundation of a multi-story building; And - prefabricated foundation of a multi-story building on highly compressible or subsidence soil; 1 – monolithic or prefabricated foundation; 2 – foundation wall; 3 – foundation wall block; 4 – waterproofing; 5 – wall of the above-ground part of the building; 6 – a layer of sand or crushed stone 50–100 mm thick; 7 – reinforced belt; 8 – first floor floor level; 9 – brick cladding; 10 – basement floor; 11 – sand cushion; 12 – above-basement ceiling

Columnar foundations are used in the construction of low-rise buildings that transmit less than standard pressure to the ground, or in the construction of frame buildings (Fig. 13.3). Columnar foundations can be monolithic or prefabricated. In the case of a wall structural system of a building under construction, they are installed at the corners of the walls, as well as at the intersection of the longitudinal external and transverse internal walls, but at least every 3–5 m. The foundation pillars are connected with reinforced concrete foundation beams of rectangular or T-section. To prevent damage from uneven settlements and bulging of the soil during heaving, a gap of 5–7 cm is created between the soil and the beams, and sand preparation is also made to a depth of 50 cm. For frame buildings of industrial construction, glass-type columnar foundations are installed.

Rice. 13.3.

A – under a brick or wooden (log or paving stone) wall: b–d – from blocks under brick pillars; d, f – under reinforced concrete columns; 1 – reinforced concrete foundation beam; 2 – bedding; 3 – blind area; 4 – waterproofing; 5 – brick pillar; 6" – pillow blocks; 7 – reinforced concrete column; 8 – Column; 9 – glass type shoe; 10 - plate; 11 – block glass

Pile foundations are mainly used for weak soils. Based on the method of immersion into the ground, a distinction is made between driven and driven piles. Driven piles are prefabricated reinforced concrete piles driven into the ground using pile drivers. Historic buildings may have wood and steel pilings. Driven piles are made directly in the ground in pre-drilled wells. Based on the nature of work in the ground, a distinction is made between rack piles, which transfer the load through soft soil to a deep, strong layer of soil, and hanging piles, which transfer the load due to frictional forces between the surface of the pile and the soil (Fig. 13.4).

Rice. 13.4.

A – piles-racks; b, c – friction piles, or hanging piles; 1 – driven piles; 2 – cast-in-place piles; 3 – reinforced concrete grillage

The structures of foundations, basement walls and ceilings above the basement are called zero-cycle constructions. They require waterproofing devices. The choice of a constructive waterproofing solution depends on the nature of the impact of ground moisture, which can be free-flowing (capillary moisture and water from rainfall and snow melting) and pressure (when the groundwater level is located above the basement floor).

In Fig. Figure 13.5 shows the waterproofing of foundations and basements at different heights of the groundwater level (GWL) above the basement floor. An expansion joint in the basement floor is created because the settlement of the foundation under the wall may be greater than the settlement of the basement floor. Without a seam, cracks appear in this area, which are called “forgotten seams.” When the water level is more than 1 m above the level of the basement floor, the reinforced concrete slab of the basement floor must be placed under the basement wall, since otherwise it may float up according to Archimedes’ law. The vertical waterproofing of the basement walls is protected by brick protective walls from scraps of reinforcement and broken glass, which can damage it when backfilling the pit. Recently, for this purpose, gluing basement walls protected with waterproofing with special synthetic tiles has been used.

Rice. 13.5.

a, b – waterproofing in the absence of groundwater pressure; c–d – the same with groundwater pressure (A - building without a basement; in other drawings there is a building with a basement); 1 – horizontal waterproofing; 2 – vertical waterproofing; 3 – crumpled fatty clay; 4 – concrete preparation; 5 – clean floor; 6 – basement wall; 7 – coating with hot bitumen; 8 – waterproofing carpet; 9 – protective wall; 10 – concrete; 11 – reinforced concrete slab, 12 – expansion joint filled with mastic, waterproofing with expansion joint

Between the wall of the foundation and basement and the wall and ceiling above the basement, horizontal waterproofing is installed, protecting the wall from moisture by capillary moisture. Currently, as a rule, glued vertical and horizontal waterproofing is installed from rolled bitumen or synthetic materials. Coating with hot bitumen is allowed only when the water level is significantly below the basement floor. In this case, under the concrete slab of the basement floor, it is desirable to install a layer of coarse gravel, covered with waxed paper, which prevents the rise of capillary moisture from the soil into the slab of the basement floor due to large voids between the gravel, interrupting capillarity. The waxed paper prevents the penetration of laitance into the gravel layer, which, when hardened, will create capillary suction.

The base part of the wall is protected by finishing slabs, which increase the durability of the base. To drain rainwater, a concrete blind area is installed around the building, which is often covered with asphalt concrete. The blind area should be 0.7-1.3 m wide with a slope i = 0.03 from the building. It prevents the penetration of surface water to the base of the foundation, keeps the soil near the basement wall dry and serves as an element of external landscaping (Fig. 13.6).

Rice. 13.6.

Walls are divided into load-bearing, self-supporting And non-load-bearing (mounted And infill walls). Depending on their location in the building, they can be external or internal. Load-bearing walls are usually called capital (regardless of their capitality, this word means basic, main, more massive). These walls rest on foundations. Self-supporting walls transfer the load to the foundations only from their own weight. Curtain walls carry their own weight load only within one floor. They transfer this load either to transverse load-bearing walls or to interfloor ceilings. Interior non-load-bearing walls are usually partitions. They serve to divide large rooms within a floor, bounded by main walls, into smaller rooms. They, as a rule, do not rest on foundations, but are installed on floors. During the operation of the building, without compromising its structural integrity, partitions can be removed or moved to another location. Such rearrangements are limited only by administrative provisions.

The walls of traditional building systems are built from small-sized elements (this is the traditional type of wall construction). These are bricks, small expanded clay concrete and aerated concrete blocks or blocks of sawn natural stone, tuff or shell rock with low thermal conductivity (Fig. 13.7). The walls of traditional buildings can also be made of wood, beams, or frame panels. This type includes half-timbered buildings in medieval towns in Europe. Here the wall frame made of logs is filled with bricks on a clay or lime binder (Fig. 13.8).

Rice. 13.7. :

a, b, ms – internal walls – load-bearing and bonding (i.e., rigidity diaphragms); a–c – brick walls; Ms. – walls made of solid or hollow lightweight concrete stones; g, g, e – walls made of natural stone; h, i – brick-concrete walls; To – brick-slag wall with brick diaphragms; l – brick wall with thermal liners made of lightweight concrete stones; m – brick-slag wall with mortar diaphragms reinforced with asbestos-cement tiles (or brackets); n – a brick or stone wall, insulated from the outside with reeds or fiberboard

Rice. 13.8.

The most common material for walls of traditional construction is solid and hollow ceramic brick (hollow brick has better thermal characteristics compared to solid brick). The weight of the brick does not exceed 4.3 kg, so that it can be lifted freely by the mason. The dimensions of ordinary bricks are standard: 250 × 120 × 65 mm. The largest face on which a brick is laid is called bed, long side – spoons and small - poke. Ceramic stones are bricks of double height - 250 × 120 × 138 mm. Clay bricks fired in special kilns. This gives them strength and water resistance. In addition to roasting ceramic products There are sand-lime bricks (a mixture of lime and quartz sand). They cannot be used in the construction of foundations and plinths of a building, since they are less water-resistant, and for laying stoves. Currently, expanded clay concrete and aerated concrete blocks measuring 200 × 200 × 400 mm, as well as super-warm Thermolux bricks are used as small-sized wall elements (Fig. 13.9). They have a low thermal conductivity coefficient of masonry of 0.18–0.20 W/(m °C) and high strength, allowing the construction of buildings up to nine floors high.

Rice. 13.9. Super-warm bricks "Thermolux"

Strength A stone wall made of small-sized elements is ensured by the strength of the stone and mortar and the laying of stones with ligation of vertical seams both in the plane of the wall and in the planes of adjacent walls. In Fig. Figure 13.10 shows solid brickwork with various bonding systems. Here, the chain one is more durable, and the six-row one is more technologically advanced, since it has a higher laying speed.

Rice. 13.10. :

A - double-row chain-link brick wall; b – brick wall of multi-row (six-row) masonry

Sustainability Such walls are ensured by their joint work with internal load-bearing structures - walls and ceilings. To do this, the elements of the external walls are inserted into the internal walls by tying the masonry and connected to the internal walls using steel embedded elements - anchors. In low-rise buildings with wooden floors, the pitch of transverse load-bearing walls should not exceed 12 m, and in houses with prefabricated reinforced concrete floors it reaches 30 m.

Durability stone walls are ensured by the frost resistance of the materials used for the outer part of the masonry. In walls made of cellular concrete, as well as in walls with external thermal insulation, the facade surface is covered with porous hydrophobic plaster or finished facing bricks or facade slabs. The connection between the cladding and the masonry is ensured by galvanized steel brackets.

Thermal protection ability Modern stone walls are provided taking into account the requirements of thermal insulation. Since 1995, according to standards in most of Russia, single-layer brick walls do not provide thermal protection requirements. Therefore, layered structures began to be used for external walls (Fig. 13.11).

Rice. 13.11. :

A – made of brick with insulation and an air gap; b – made of monolithic reinforced concrete with insulation and brick cladding

The main elements of brick walls are openings, lintels, piers, plinth and cornice.

Jumpers made of brick (ordinary or arched) are installed above the openings for architectural reasons. Ordinary - above openings no more than 2.0 m on temporary wooden flooring. Steel reinforcement anchored into the walls is laid in the bottom row along the cement mortar layer. The part of the wall above the window, at least four rows high, sometimes reinforced, is built along it. Arched lintels take the load well, but are labor-intensive to manufacture. They are arranged for architectural reasons and can have different shapes - arched and wedge-shaped. The most common lintels in mass construction are prefabricated bars made of reinforced concrete (load-bearing - reinforced and non-load-bearing). For non-load-bearing lintels, the embedment in the walls is at least 125 mm, and for load-bearing lintels - 250 mm. Various types jumpers are shown in Fig. 13.12.

Rice. 13.12. :

a-g – precast concrete lintels (a, b – block (type B); V – slab (type BP); G – beam (type BU); d – arched; e – flat wedge; 1 – keystone; 2 – jumper heel

The plinth - the lower part of the outer wall (Fig. 13.13), exposed to adverse atmospheric and mechanical influences - is made of well-fired ceramic bricks, followed by finishing with plaster, facing bricks, stone or ceramic slabs. The base is exposed to rain falling on the ground, melt water, and snow cover adjacent to it. This moisture wets the base material and, during freezing and thawing, contributes to its destruction. The plinth also has architectural significance and gives the building the impression of greater stability. The upper ledge of the plinth (edge) is usually located at the floor level of the first floor, thereby emphasizing the beginning of the volume of the building used for its main purpose.

Rice. 13.13.

A – lined with brick; b – lined with stone blocks; V – lined with slabs; G – plastered; d – from concrete blocks undercut; e – from reinforced concrete panels undercut; 1 – foundation; 2 – wall; 3 – blind area; 4 – waterproofing; 5 – burnt brick; 6 – basement stone blocks; 7 – side plinth stone; 8 – facing slabs; 9 – plaster; 10 – roofing steel; 11 – concrete block; 12 – foundation wall panel; 13 – first floor floor structure

Below the floor of the first floor, a ground floor, basement or underground is arranged. Ground floor- This is a room below the first floor, the height of which is more than half above ground level. Basement- This is a room below the first floor, the height of which is less than half above ground level. Underground- this is a room under the floor of the first floor, the height of which is equal to the distance from the lower ceiling to the ground level. The underground protects the building structure from direct exposure to groundwater. This may be the so-called cold underground. Sometimes semi-through technical undergrounds are arranged to accommodate various utilities (water supply inlets, sewerage outlet pipes, central heating pipes). In this case, the basement part of the wall must protect the technical underground, as well as the basement and basement floors from freezing.

Cornices(Fig. 13.14) - horizontal projections from the plane of the wall. They are designed to drain rainwater away from the wall surface and often serve architectural purposes. Along the height of the wall there may be several small cornices in the form of belts, forming architectural divisions along the height of the building. The topmost cornice is called the crowning cornice. The extension of the brick cornice should not exceed 300 mm. The removal of a reinforced concrete cornice can be very large.

Rice. 13.14. :

A – general diagram of the wall with waterproofing devices; b – a cornice formed by an overlap of bricks; c, d – cornices made of prefabricated reinforced concrete slabs: d – a cornice formed by the overhang of a continuous covering panel; e – cornice formed by the overhang of the roofing panel of the ventilated covering; and – parapet with a flat covering with internal drainage; 1 – roof overhang; 2 – waterproofing of architectural belt; 3 – window sill drain; 4 – waterproofing of the plinth cordon; 5 – base; 6 – waterproofing; 7 – blind area; 8 – drain and gutter made of galvanized steel; 9 – fencing; 10 – drainpipe; 11 – drying air

Wooden walls, according to their design solutions, are divided into log, cobblestone, frame-sheathing And panel Coniferous wood, the most common in Russia, is an effective building material and has good mechanical and thermal insulation properties. Previously, the main disadvantages of wooden structures were their susceptibility to rotting and flammability. Modern technologies make it possible to eliminate these shortcomings.

The structures of log walls are shown in Fig. 13.15. Cobblestone walls (Fig. 13.16) are erected from prefabricated beams at the factory, which eliminates manual processing of logs and tying corners. Particular attention should be paid to caulking the seams between the crowns (horizontal rows of logs or beams). During the first 1.5-2.0 years, a log house with a floor height gives a height settlement of 15–20 cm, which should be taken into account when constructing it.

Rice. 13.15.

A - log house; b – pairing logs and beams with a secret frying pan; V – pairing of logs and beams with a through pan; G - cutting the corner with the remainder “into the bowl”; d – cutting corners without leaving a trace; e – processing of logs for felling without residue; 1 – log crowns; 2 – caulk; 3 – insert tenon; 4 –protective board; 5 – secret spike; 6 – groove for a hidden tenon; 7 – low tide; 8 – plinth

Rice. 13.16. :

A – sections of cobblestone walls; b–d – pairing the beams in the corner and with the inner wall; 1 – timber; 2 – caulk; 3 – dowel; 4 – thorn; 5 – root spike

The stability of log and cobblestone walls is ensured by their connection in the corners and at intersections with transverse walls located at distances of no more than 6–8 m from each other. At large distances, walls can bulge. To prevent bulging, they are strengthened with compression from vertical paired beams, installed on both sides of the wall and fastened together in height with bolts of 1.0-1.5 m.

Frame-cladding wooden walls(Fig. 13.17) are much simpler to manufacture and require less wood than log or cobblestones. They can be arranged directly on site. The racks, placed at a certain pitch, taking into account the location of windows and doors, are fastened from below and above with horizontal strapping beams and have connecting struts at the corners of the building. The frame is sheathed with inside. Then a rolled vapor barrier is laid from a special vapor-proof material or from polyethylene film. After this, insulation boards (mineral wool, fiberglass or expanded polystyrene) are installed. The outside walls are sheathed with 2.5 cm thick boards or siding, i.e. artificial facing elements in the form of boards made of metal or synthetic material. Frame-sheathing parts provide any degree of thermal protection. The disadvantages are the busy nature and the possibility of insulation settling during operation. In Fig. 13.18 shows the designs wooden walls sandwich type, allowing you to preserve the appearance of a log or cobblestone wall, but ensuring compliance with modern requirements for thermal protection.

Rice. 13.17. :

A – general form frame; b – supporting the beams on the outer wall in the corner; V - supporting beams on interior wall; 1 – bottom trim 2 (50 × 100 mm); 2 – frame stand 50 × 100 mm; 3 – top trim 2 (50 × 100 mm); 4 – floor beams 50 × 200 mm; 5 – spacer 500 × 200 mm; 6 – beam-lintel; 7 – shortened stand; 8 – rigidity braces; 9 – additional racks in the corners 50 × 100 mm; 10 – additional opening post; 11 - base; 12 – blind area; 13 – insulation between the racks; 14 – insulation on the outside; 15 – plaster; 16 – foundation beam; 17 - anchor bolts

Rice. 13.18.

1 – wooden beam; 2 – insulation; 3 – internal cladding board; 4, 6 – semi-brsvno; 5 – rounded timber; 7 – decorative croaker

Panel walls are assembled from enlarged factory-made elements - insulated wall panels. At the same time, houses can be frame or frameless. In the second case, the vertical racks of the shields act as frame racks. The shields are installed on the lower frame and fastened on top with the top frame.

Post-and-beam design used in frame buildings, as well as in buildings with an incomplete frame (external load-bearing walls, inside - pillars and cisterns). In buildings with an incomplete frame, pillars are installed instead of internal load-bearing walls where it becomes necessary to open up the internal space. Frame structures are the most common in public and industrial buildings (Fig. 13.19, 13.20). The racks (columns) of the frame work in central and eccentric compression. Under load they can become longitudinally bent.

Rice. 13.19.

1 – column with a cross section of 400 × 400 mm; 2 – floor spacer; 3 – T-section crossbar; 4 – flooring; 5 – joint of columns

Rice. 13.20. :

A – general view of the unit; b – design and design diagram of the unit; 1 – Column; 2 – crossbar; 3 – flooring spacer; 4 – embedded parts; 5 – top cover; 6 – “hidden console” of the column; 7 – welds

The horizontal element of a post-beam system is a beam (crossbar) - a rod that acts in transverse bending under the action of a vertical load (Fig. 13.21). It has a continuous cross-section for spans up to 12 m. For larger spans, it is advisable to use beam structures with a through section in the form of trusses (Fig. 13.22). The walls of buildings with a reinforced concrete frame can be self-supporting, infill walls (installed on reinforced concrete floors, transferring the load to the floors and working under the load from their own weight within one floor) and curtain walls, fixed to the columns and crossbars of the frame.

Rice. 13.21.

a, g – single-pitched and flat I-section; b – the same for multi-slope coverings; V – lattice for multi-slope coverings; d – unit for supporting the beam on the column; 1 - anchor bolt; 2 - washer; 3 – base plate

Rice. 13.22.

A – segmental; b – arched, unbraced; V - with parallel belts; G – trapezoidal

Floors They are horizontal load-bearing structures resting on load-bearing walls or pillars and columns and absorbing the loads acting on them. The floors form horizontal diaphragms that divide the building into floors and serve as horizontal stiffening elements for the building. Depending on the position in the building, ceilings are divided into interfloor, attic - between the upper floor and the attic, basement - between the first floor and the basement, lower - between the first floor and the underground.

In accordance with the impacts, the ceiling structures are subject to different requirements:

• static – ensuring strength and rigidity. Strength is the ability to withstand loads without breaking. Rigidity is characterized by the value of the relative deflection of the structure (the ratio of deflection to span). For residential buildings it should be no more than 1/200;
• soundproofing – for residential buildings; ceilings must ensure sound insulation of separated rooms from airborne and impact noise (see Section IV);
• thermotechnical – applied to floors separating rooms with different temperature conditions. These requirements are established for attic floors, floors over basements and driveways;
• fire protection - are installed in accordance with the class of the building and dictate the choice of material and structures;
• special – water and gas impermeability, bio- and chemical resistance, for example in sanitary facilities, chemical laboratories.

According to the design solution, floors can be divided into beam and non-beam, according to material - into reinforced concrete slabs (prefabricated and monolithic) and into floors with steel, reinforced concrete or wooden beams, according to the installation method - into prefabricated, monolithic and precast-monolithic.

Beamless (slab) floors are made of reinforced concrete slabs (panels) having different structural support patterns (Fig. 13.23–13.25). When supported on four or three sides, the slabs act like plates and have deflections in two directions. Therefore, the load-bearing reinforcement is located in two mutually perpendicular directions. These slabs have a solid cross-section. The slabs, supported on two sides, have working reinforcement located along the span. To make them easier, they are most often made multi-hollow (Fig. 13.26). In the case of supporting slabs at corners and other atypical support patterns, the slabs are reinforced in a certain way with increased reinforcement at the points of support.

Rice. 13.23.

a – c longitudinal lines of supports; b – with transverse support lines; V - supported on three or four sides (along the contour); 1 – floor panels resting on load-bearing walls; 2 – internal longitudinal or transverse load-bearing wall; 3 – external load-bearing wall; 4 – floor panel resting on the purlin; 5 – runs; 6 – columns; 7 – floor panel the size of a room, supported by four (three) load-bearing walls

Rice. 13.24. Flooring slabs for spans 9 (i), 12(b) and 15 (in) m:

1 – mounting loops; 2 – longitudinal ribs; 3 – transverse ribs

Rice. 13.25.

A - general form; b – diagram of supporting the slab on the column; 1 – plate; 2 – capital; 3 - Column

Rice. 13.26.

Beam floors are assembled from load-bearing beams and the filling between them - roll-up. Beams can be made of wood, reinforced concrete or metal. Floors according to wooden beams suit only one and two-story houses. In more tall buildings The use of ceilings on wooden beams is prohibited by fire regulations. The arrangement of wooden floors is shown in Fig. 13.27. To ensure sound insulation, a soundproofing layer is placed on the runway, making the structure heavier to protect against airborne noise. This can be sand, broken bricks or effective porous materials with increased sound absorption. Plank floors in wooden floors are made using joists laid on beams with elastic soundproofing pads. To ventilate the underground space, install in the corners of the room ventilation holes, closed with bars. The ceilings are plastered or lined with sheets of dry plaster. Sometimes knurling boards are sanded and coated with colorless varnish, preserving the texture of the wood.

Rice. 13.27.

1 – cranial bars; 2 – beam; 3 – parquet; 4 – black floor; 5 – lag; 6 – plaster; 7 – roll up; 8 – clay lubrication; 9 – backfill

Floors on reinforced concrete beams consist of T-section beams installed in increments of 600, 800 or 1000 mm, and inter-beam filling made of concrete roll slabs, hollow lightweight concrete blocks or hollow ceramic liners (Fig. 13.28). The bottom of the ceiling is plastered. A leveling cement-sand screed is placed on top, on which the floor structure is laid on a soundproofing pad.

Rice. 13.28.

a, b – monolithic; c, d – prefabricated on reinforced concrete beams with gypsum slabs; d, f – the same, with lightweight concrete liners ( b – junction of a monolithic section with a prefabricated floor on reinforced concrete beams; d – example of a linoleum floor); 1 – monolithic reinforced concrete; 2 – elastic gasket; 3 – plank floor but lagam; 4 – sand no less 20 mm; 5 – prefabricated floor is conventionally shown; 6 – roofing felt; 7 – reinforced concrete T-beam; 8 – gypsum or lightweight concrete slab; 9 – insulation (mineral wool, etc.); 10 – vapor barrier; 11 – wooden frame; 12 – double-hollow lightweight concrete liner; 13 – linoleum on a layer of cold mastic from waterproof binders; 14 – lightweight concrete screed 20 mm

Floors on steel beams are currently used more often in reconstruction than in new construction. Load-bearing I-section beams are installed in increments of 1.0-1.5 m. The ends of the beams are placed on the walls with concrete distribution pads installed in the support areas. Design options are shown in Fig. 13.29. In public buildings, as well as in hotels, floors are often used with metal beams on which corrugated sheets (profiled galvanized steel sheets) are laid; then a monolithic concrete slab 60–100 mm thick is laid over it over the ridges of the corrugated sheet. The depressions of the corrugated sheet serve simultaneously as the formwork of the ribbed concrete slab and its stretched reinforcement. Sometimes additional reinforcement cages are installed in the ribs, and reinforcement mesh. A suspended ceiling is installed along the lower chords of steel beams. In the space between the ribbed plate and suspended ceiling Usually various communications, ventilation ducts, electrical wiring, etc. are located. The arrangement of such an overlap is shown in Fig. 13.30.

Rice. 13.29.

A – resting the ends of the beams on the walls; b – anchor fastening detail; V – flooring filled with reinforced concrete monolithic slab; G - the same, brick vaults; 1 – steel beam; 2 – concrete pad; 3 – steel anchor; 4 – sealing with concrete; 5 – bolt; 6 – reinforced concrete monolithic slab; 7 – lightweight concrete; 8 – ceramic tiles over a layer of cement mortar; 9 – steel mesh; 10 – plank floor along the joists; 11 – two layers of roofing felt; 12 – soundproofing layer; 13 – plastering with cement mortar; 14 - brick vault

Rice. 13.30.

Monolithic floors are erected on the construction site using different types of formwork. They can be ribbed, consisting of main and secondary monolithic beams and a monolithic slab, coffered with mutually intersecting beams of the same height, and in the form of a continuous monolithic slab supported by vertical load-bearing structures (Fig. 13.31). To lighten the structure, prefabricated monolithic floors are used with the installation of panel formwork and the installation of rows of ceramic or lightweight concrete liners on it. Triangular reinforcement cages are installed between the rows of liners. Reinforcing mesh is laid on top of the liners. Then the ceiling is poured with concrete. After the concrete hardens, the formwork is removed.

Rice. 13.31.

Foundations, walls, frame elements and ceilings are the main load-bearing elements of a building. They form the load-bearing skeleton of the building - a spatial system of vertical and horizontal load-bearing elements. The load-bearing frame carries all the loads on the building. In order for it to be stable under the influence of horizontal loads (wind, seismicity, crane equipment in industrial buildings), it must have the necessary rigidity. This is achieved by constructing longitudinal and transverse walls - rigidity diaphragms, rigidly connected to the frame columns or to load-bearing longitudinal or transverse walls. Rigidity is also ensured special connections and horizontal floor discs.

The supporting frame determines design diagram building.

Roof protects premises and structures from precipitation, as well as from heating by direct rays of the sun ( solar radiation). It consists of a load-bearing part (rafters and sheathing in buildings made of traditional structures) and reinforced concrete roofing slabs in industrial buildings, as well as an outer shell - roofs, directly exposed to atmospheric influences. The roof consists of a waterproof so-called waterproofing carpet and a base (lathing, flooring). The material of the waterproofing carpet gives the name to the roof (tile, metal, ondulin, etc.), since such qualities of the roof as waterproofness, non-flammability and weight depend on its properties. Roofs are sloped to drain rain and melt water. The steepness of the slopes depends on the roofing material, its smoothness, and the number of joints through which water can penetrate. The smoother the material, the fewer joints and the denser they are, the flatter the roof slopes can be. During thaws, the snow lying on the slopes is saturated in its lower layers with melt water, which flows through leaks roofing material inside the building. Therefore, in tile and metal roofs, the slopes must be significant. However, as the roof slope increases, the roof area and attic volume increase.

For lighting and ventilation of attics they are made dormer windows, which should be located closer to the roof ridge and serve to exhaust air from the attic. To ensure the flow of ventilation air into the attic space, it is necessary to arrange stuck – openings or cracks in the roof eaves.

For the same purpose, hatches for exiting the attic onto the roof, located closer to the edge of the roof (Fig. 13.32), can serve.

Rice. 13.32.

1 – zastrakha (inflow); 2 – dormer window (hood); 3 – exhaust hole in the pediment; 4 - louvre grille

Such attics are called cold. The temperature inside them should be close to the outside temperature. In this case, the roof will not have leaks. Engineering equipment and pipelines with water cannot be located in such attics, as it may freeze. In buildings over 12 floors, built in the central and northern regions, warm attics or technical floors are used (Fig. 13.33). The roof of such attics is insulated. In warm attics, positive temperatures are maintained in winter by ventilation air entering the attic from ventilation ducts ending in the attic. Exhaust ventilation air is removed from the attic space through large cross-section pipes or ducts (one per section). Warm attics house various engineering equipment. Warm attics also protect rooms from roof leaks.

Rice. 13.33.

a, b – with a cold attic with roll (A) and rollless ( 6 ) roof; c, d – with a warm attic with a roll (V) and roll-free (d) roofing; d, f – with open attic with roll-up (d) and rollless (f) roofing; 1 – support element; 2 – plate attic floor; 3 – insulation; 4 – non-insulated roofing slab; 5 – rolled carpet; 6 – drainage tray; 7 – support frame; 8 – protective layer; 9 – vapor barrier layer; 10 – strip of roofing material; 11 – support element of the fascia panel; 12 – rollless roofing slab; 13 – waterproofing layer of mastic or painting compositions; 14 – U-shaped cover plate; 15 – drainage funnel; 16 – ventilation unit (shaft); 17 – head of the ventilation unit; 18 – lightweight concrete single-layer roofing slab; 19 – elevator machine room; 20 – lightweight concrete tray slab; 21 – two-layer roofing slab; 22 – non-insulated fascia panel; 23 – insulated fascia panel

A roof combined with an attic floor (without a technical floor) is called unventilated combined roof or coating. If there is an air gap between the roof and the attic floor that connects with the outside air, then such a roof is called ventilated combined roof (Fig. 13.34).

Rice. 13.34.

A – separate structure with roll roofing; b – separate structure with roll-free roofing; V – combined panel single-layer structure; G – the same, three-layer; d – the same, construction production; 1 – attic floor panel; 2 – insulation; 3 – frieze panel; 4 – rollless roof roof panel; 5 – supporting element; 6 – single-layer lightweight concrete roofing panel; 7 – rolled carpet; 8 – three-layer roofing panel; 9 - cement strainer; 10 – a layer of expanded clay on a slope; 11 – a layer of cushioning roofing felt on mastic

Well-made flat combined roofs can be used as recreation areas and for other purposes.

The pitched rafter roof is traditional. Depending on the shape of the building in plan, the shape of the roofs can be different (Fig. 13.35). The supporting structures of a traditional pitched roof are called rafters. Rafters can be inclined or hanging. For large spans, combined rafter structures are used, where the rafter legs rest on the walls and a post in the middle of the span, which in turn rests on the lower belt of the rafters, which is the beam of the suspended attic floor (Fig. 13.36). The hanging rafter trusses are placed in increments of 3.0-3.6 m and are united by longitudinal horizontal beams, on which the racks of lighter intermediate layered rafters are supported in increments of 1.0-1.2 m.

Rice. 13.35.

A – single slope; b – gable; V - roof with attic; G - tent; d, f – general view and plan of the roof of the house; and - example of constructing a roof slope; h,i – half-hip ends gable roof; 1 – eaves; 2 – dormer window; 3 – pediment tympanum; 4 – gable; 5 – ridge; 6 – stingray; 7 – forceps; 8 – valley (the lowest line of coverage for organizing drainage); 9 – bevel rib; 10 – hip (the slope of a hip roof, triangular in shape and located on the end side of the building); 11 – half hip

Rice. 13.36.

A – inclined rafters for pitched roofs; b - the same for gable slopes; V - the same, hanging; G – the same, combined; 1 – Mauerlat (beam lying on the wall and serving to support rafter legs or tighten hanging rafters); 2 – internal pilaster; 3 – crossbar; 4 – fight; 5 – rafter leg; 6 – puff; 7 – suspension; 8 – suspended attic beam

All supporting units of rafter structures are located 400–500 mm above the upper level of the attic floor. The structure of organized external drainage is shown in Fig. 13.37, 13.38. A comparison of steel gutters on the roof and eaves and hanging gutters shows that hanging gutters have the best performance, with a much lower risk of leaks. To avoid frost destruction of the external drainage system and the formation of ice and icicles on gutters and eaves and in drainpipes, winter time arrange a heating system for curtain rod units.

Rice. 13.37.

A – section along the roof; b – rebate (connection of metal flat roofing sheets) lying single; V – the same, double; G - standing single; d – the same, double; 1 – T-shaped steel crutch through 700 mm; 2 – funnels drainpipe; 3 – picture of the roof overhang; 4 – wall gutter; 5 – picture of the wall gutter; 6 – recumbent fold; 7 – roofing steel; 8 – standing seam; 9 – ridge board; 10 – bars and sheathing boards; 11 – clasps; 12 – twisted wire; 13 – crutch

Rice. 13.38.

A - roof section: b – skate device option: V - valley device; 1 – hook for hanging gutter: 2 – roofing steel; 3 – corrugated asbestos-cement sheet of ordinary profile; 4 – continuous sections of sheathing at the eaves and in the valleys; 5 – sheathing bars; 6 – ridge bars; 7 – shaped ridge part; 8 – nail or screw; 9 – elastic gasket; 10 – twist

The basis of the roof of pitched roofs is sheathing for all types sheet materials and shingles nailed to the rafters and fillets. The lathing can be sparse (for sheet steel and tiles), and also continuous - for modern roofing materials such as “Icopal” or “Ondulin”. At lower junctions of slopes (troughs, valleys), as well as along the eaves, in addition to continuous sheathing, before laying the main roofing material, a covering of steel sheets is installed in order to protect against leaks.

Stairs serve for communication between floors. The rooms in which stairs are located are called staircases. The walls of staircases in buildings above two floors must have high fire resistance, since staircases are ways of evacuating people in case of fire. In buildings with a height of 12 floors and above, staircases must be smoke-free (Fig. 13.39). The dimensions of the steps should be determined based on the normal human step: 2 a + b = 600: 630 mm (where A - height, b – step depth). Based on this condition, the riser height (a) is set to 150–180 mm. In multi-storey buildings, stairs between floors have steps of 150 × 300 mm. In wooden stairs inside apartments, the riser height can reach 180 mm or more. Staircase structures mainly consist of marches And sites (Fig. 13.40, 13.41) and are protected by railings. In houses of traditional construction, stairs made of small-sized elements are used along stringers (obliquely laid beams of staircases) and under-strut beams (Fig. 13.42). Design wooden stairs shown in Fig. 13.43.

Rice. 13.39.

Rice. 13.40.

1 – landings; 2 – flights of stairs; 3 – fragment of the fence

Rice. 13.41.

1 – upper frieze step; 2 – fencing stand; 3 – landing

Windows (light openings) arranged for lighting and ventilation (natural ventilation or aeration) of premises.

Rice. 13.42.

Rice. 13.43.

They consist of window openings, frames or boxes and filling openings, called window sashes. Windows are designed depending on the requirements of the standards for natural lighting. They connect the external space with the internal environment and must transmit a sufficient amount of natural light and provide insolation, i.e. penetration sun rays into the room, create a visual connection between the external and internal space. At the same time, windows must protect the room from low temperatures in winter, from overheating in summer, from street noise, from rain and wind. Designing light openings is a complex task. Its solution is studied in the course “Physics of the Environment and Enclosing Structures” and in the master’s program. In multi-story buildings, window openings are located in the walls one above the other. In this case, the load transmitted to the external walls is absorbed by the walls. In frame buildings, windows can be located on the facade as desired. In Fig. 13.44 and 13.45 show the design of traditional windows with paired and separate sashes, respectively.

Rice. 13.44.

1 – tarred tow (for work in winter) or tow soaked in gypsum solution (for work in summer); 2 – cement mortar; 3 – mastic; 4 – platband; 5 – drain side 20 mm high; 6 – drain made of galvanized steel; 7 – window sill; 8 – metal strip 20 × 40 mm (3 pieces per opening)

Rice. 13.45.

1 – box; 2 – tarred tow; 3 – nail; 4 – wooden cork; 5 - a loop; 6 – binding binding; 7 – glass; 8 – layout; 9 – glazing bead; 10 – window trim; 11 – window; 12 – sashes; 13 – low tide; 14 – croaker; 15 – solution; 16 – ebb made of galvanized steel; 17 – windowsill

Doors There are external entrances, entrances to the apartment, intra-apartment and balcony. In this regard, they are subject to various requirements for protection from unwanted penetration, fire resistance, thermal insulation, and noise protection.

The considered structural elements are typical for both civil and industrial buildings. However industrial building have some differences in their structure. Industrial buildings are one-, two- and multi-story. Single-story buildings (Fig. 13.46) are used for various industries with heavy equipment or where products of significant weight are produced. To work with such equipment, overhead and overhead cranes are used. The floor is laid on the ground. Single-story industrial buildings usually do not have basements or attics. The structures of industrial buildings, with the exception of historical ones, are mainly framed, consisting of columns arranged in rows on which rafter structures, mainly trusses, are laid. The distance between two parallel rows of columns is called in flight, its size ranges from 12 to 36 m. However, in buildings where large-sized products are produced (airplanes, ships, nuclear reactors), the span size can be significantly larger (60, 72, 84 m or more). If a building has several spans, it is called multi-span. For natural light mid-span light openings are installed in the roof of the building - lanterns Some mud lanterns can also be used or specifically for aeration.

Rice. 13.46.

Multi-storey industrial buildings (Fig. 13.47) usually have a frame as a load-bearing frame, consisting of columns and crossbars, on which the floor structures are laid. Technological equipment it is installed on floors, so spans do not exceed 12 m. For the same reasons, multi-storey industrial buildings are intended for industries with relatively light equipment (electrical, light, textile, food industry, etc.). In multi-storey industrial buildings, technical floors and basements are usually arranged. When using natural lighting, the width of such buildings does not exceed 36 m.

Rice. 13.47.

A - facade; b – plan; V - cross section

Two-story industrial buildings have small spans (6–9 m) in the lower floor. On the second floor, the spans can be the same as in conventional one-story industrial buildings. The lower floor houses auxiliary production and administrative premises, as well as warehouses, etc. The top floor houses the main production facilities, located in large spans. This arrangement of industrial buildings allows saving expensive building space.

Fundamentals of building design solutions

By purpose building structures are divided into load-bearing, enclosing and combined.

Load-bearing structures– building structures that absorb loads and impacts and ensure the reliability, rigidity and stability of buildings. Load-bearing structures that form the skeleton of a building (structural system) are classified as basic: foundations, walls, individual supports, floors, coverings, etc. the rest of the supporting structures are considered secondary, for example, lintels over openings, stairs, blocks of elevator shafts.

Fencing structures– building structures designed to isolate internal volumes in buildings from the external environment or from each other, taking into account regulatory requirements for strength, thermal insulation, waterproofing, vapor barrier, air tightness, sound insulation, light transmission, etc. The main enclosing structures are curtain walls, partitions, windows, stained glass windows, lanterns, doors, gates.

Combined structures– building structures of buildings and structures for various purposes, performing load-bearing and enclosing functions (walls, floors, coverings).

According to spatial location, carriers building structures are divided into vertical and horizontal.

Horizontal load-bearing structures- coverings and ceilings - absorb all the vertical loads falling on them and transfer them floor-by-floor to vertical load-bearing structures (walls, columns, etc.), which, in turn, transfer the loads to the base of the building. Horizontal load-bearing structures, as a rule, also play the role of hard drives in buildings - horizontal diaphragms of rigidity; they perceive and redistribute horizontal loads and impacts (wind, seismic) between vertical load-bearing structures.

The transfer of horizontal loads from floors to vertical structures is carried out according to two main options: with distribution to all vertical load-bearing elements or only to individual vertical stiffening elements (diaphragm walls, lattice wind braces or stiffening trunks). At the same time, all other supports work only for vertical loads. An intermediate solution is also used: the distribution of horizontal loads and impacts in various proportions between stiffeners and structures that work primarily to absorb vertical loads.

Diaphragm floors ensure compatibility and equality of horizontal movements of vertical load-bearing structures under wind and seismic influences. Such compatibility and alignment are achieved by rigidly pairing horizontal load-bearing structures with vertical ones.

Horizontal load-bearing structures of permanent civil buildings with a height of more than two floors are of the same type and are usually a reinforced concrete disk - prefabricated, precast-monolithic or monolithic.