External walls are not only structural elements, their outer side is an element of the building facade. Therefore, the walls (their configuration, vertical and horizontal divisions, proportions) individual elements, plinths, cornices, decoration, etc.) determine the nature of the architecture and tectonics of the building. At the same time, the facade does not exist independently of the purpose of the building, its planning structure, materials and structures of external walls, but is a reflection of them.
Impacts on walls. Both external and interior walls buildings are exposed to a number of factors closely related to processes occurring inside and outside the building.
Force influences include:
Load from floors and coverings (roofs);
Load from uneven soil deformation (precipitation, heaving);
Seismic impacts.
Non-force influences are:
Precipitation;
Water vapor contained in indoor air;
Soil moisture;
Solar radiation;
Outside air temperature, its changes;
Aggressive substances contained in the air;
Airborne noise from outside and inside the building.
Walls must satisfy the following requirements:
Be strong and stable;
Have durability corresponding to the class of the building;
Comply with the fire resistance level of the building;
Be an energy-saving element of the building;
Meet air and sound insulation requirements;
To be industrialized in order to increase labor productivity;
Possess, if possible, minimal weight and material consumption;
Meet modern architectural and artistic quality;
Be economical during construction and operation.
Accounting for all modern requirements necessitated dividing the outer walls into layers separate for their purpose. The walls have become multi-layered, consisting of functionally separated elements: load-bearing capacity is provided by a more durable structural layer, protection from cooling or overheating is provided by a fragile but highly effective thermal insulation layer, and, finally, giving good looking– finishing layers.
Internal walls are designed based on strength and sound insulation. These two requirements in their own way physical properties coincide, the denser the material of the inner wall, the more durable and less sound conductive it is.
However, here too, layered structures with alternating dense and loose layers are more effective in sound insulation, which in each individual case must be determined by calculation.
The architect’s task is to develop a solution in which the wall materials and their design would, if possible, satisfy all the requirements for them and contribute to obtaining the most optimal solution. In the design process, it is necessary to take into account the following basic principles as initial ones: preconditions:
Climatic factors of the construction area (outside air temperature in winter and summer, precipitation, wind speed, insolation);
Range of available building materials;
Technical capabilities of construction and installation enterprises;
Special construction conditions (seismic, soil, etc.);
Classification of walls. Depending on the load perception, the walls of buildings can be load-bearing, self-supporting or non-load-bearing.
By position in the building walls are divided into internal And external(along the perimeter of the building).
By type of base material bearing and self-supporting walls can be wooden, stone, concrete, combined. The following basic materials and products are used for walls:
Wood (logs, beams, boards, panels);
Burnt clay (brick, stones);
Silicate mass (brick);
Natural stone;
Stabilized soil (blocks);
Lightweight concrete (stones, blocks, panels, monolith);
Cellular concrete (stones, blocks, monolith);
Heavy concrete (panels, monolith).
Depending on the type and size wall products used are:
- from small-sized wall products– bricks, stones, small blocks;
- large-element– from wall elements with a height of 1/4 to the full height of the floor or more; Large-element walls are divided into large-block and large-panel.
By construction method differentiate masonry walls(assemblies) of small-piece products, prefabricated, monolithic, precast-monolithic.
By design features there are walls single-layer(usually internal) and layered, continuous And hollow.
By the presence and location of thermal insulation external walls are divided into:
- walls without special device thermal insulation– from structural and thermal insulation materials (wood, wood concrete, cellular concrete, polystyrene concrete);
- walls with thermal insulation layers, located inside the wall, on the outside of the structural layer of the wall, on the outside and inner sides together.
By the presence of a special air gap(layers) walls are divided into:
- ventilated– with air gaps located either inside the structural layer (between the structural layers) or between the insulation and the protective cladding;
- unventilated– without an air gap.
Wall structural system buildings can be designed in a wide variety of layout options (schemes) load-bearing walls– transverse and longitudinal, internal and external, rectilinear and curvilinear, parallel, radial, concentric, etc. The determination (purpose) of the location of load-bearing walls is directly dependent on the solution of the floors (coverings, roofs) of the building - the supports or junctions of their elements on the walls.
During the design process, the quality should be taken into account original the following main preconditions:
Climatic factors of the construction area (summer and winter outside air temperature, precipitation, wind speed, insolation);
Special construction conditions (part-time work, seismic, soil, etc.);
Characteristics of the building (purpose, number of floors, degree of fire resistance, temperature and humidity conditions, etc.);
Technical capabilities of construction organizations;
Financial capabilities of the customer.
By purpose walls are external and internal, and by load perception - load-bearing and non-load-bearing.
Depending on the materials used share the following types of walls:
wooden from logs, beams, wooden frames;
brick made of solid and hollow clay, ceramic and sand-lime bricks and blocks;
stone made from cobblestone, limestone, sandstone, shell rock, tuff, etc.;
lightweight concrete made of gas silicate, expanded clay concrete, polystyrene, slag concrete, wood concrete, sawdust concrete;
soil concrete made of adobe, compacted pear.
By constructive decision walls are:
chopped from logs and assembled from wooden beams;
small block made of bricks and small blocks weighing more than 50 kg;
panel or panel made of ready-made elements walls one floor high;
framed from racks and frames covered with sheet or molded materials;
monolithic from concrete and soil;
composite or multilayer using various materials and designs.
Materials for the construction of walls and their design solutions are selected taking into account local climatic conditions, economics, the specified strength and durability of the building, internal comfort and architectural expressiveness of the facades.
Natural stones and solid bricks have the greatest strength and durability. At the same time, in terms of their heat-protective qualities, they are significantly inferior to lightweight concrete, efficient brick and wood. Their use in “ pure form“Without combination with other, less thermally conductive materials, it is justified only in the southern regions of the country.
When building brick walls, you should strive for lightweight masonry, using efficient bricks and creating voids using warm mortar. Solid brick walls made of solid brick a thickness of more than 38 cm is considered impractical.
Reliable in operation and 1.5 - 2 times cheaper than brick ones concrete walls based on slag, expanded clay or sawdust using cement. If you use pre-fabricated lightweight concrete blocks, you can significantly reduce the seasonal construction time.
The traditional material for the walls of low-rise buildings is wood. According to sanitary and hygienic requirements, chopped and cobblestone walls are the most comfortable. Their disadvantages include low fire resistance and sedimentary deformations in the first 1.5 - 2 years.
If lumber and effective insulation are available, frame walls are quite justified. They, like chopped ones, do not require massive foundations, but unlike them they do not have post-construction deformations. When facing frame walls bricks significantly increase their fire resistance and capital strength.
In southern regions with sharp changes in day and night outside air temperatures, walls made of soil concrete (adobe) “behave well”. Due to their great thermal inertia (they heat up and cool down slowly), they create an optimal thermal regime in such a climate.
You watched: Types of walls
Constructions of external walls of civil and industrial buildings
The structures of external walls of civil and industrial buildings are classified according to the following criteria:
1) by static function:
a) load-bearing;
b) self-supporting;
c) non-load-bearing (mounted).
In Fig. 3.19 shown general form these types of external walls.
Load-bearing external walls perceive and transfer to the foundations their own weight and loads from adjacent building structures: floors, partitions, roofs, etc. (at the same time they perform load-bearing and enclosing functions).
Self-supporting external walls perceive vertical load only from their own weight (including the load from balconies, bay windows, parapets and other wall elements) and transfer them to the foundations through intermediate load-bearing structures - foundation beams, grillages or plinth panels (at the same time they perform load-bearing and enclosing functions).
Non-load-bearing (curtain) external walls floor by floor (or through several floors) they rest on adjacent supporting structures of the building - floors, frames or walls. Thus, curtain walls perform only an enclosing function.
Rice. 3.19. Types of external walls according to static function:
a – load-bearing; b – self-supporting; c – non-load-bearing (suspended): 1 – building floor; 2 – frame column; 3 – foundation
Load-bearing and non-load-bearing external walls are used in buildings of any number of floors. Self-supporting walls rest on own foundation, therefore their height is limited due to the possibility of mutual deformations of the external walls and internal structures of the building. The taller the building, the greater the difference in vertical deformations, so, for example, in panel houses It is allowed to use self-supporting walls with a building height of no more than 5 floors.
The stability of self-supporting external walls is ensured by flexible connections with the internal structures of the building.
2) According to the material:
A) stone walls They are built from brick (clay or silicate) or stones (concrete or natural) and are used in buildings of any number of storeys. Stone blocks are made from natural stone (limestone, tuff, etc.) or artificial (concrete, lightweight concrete).
b) Concrete walls made of heavy concrete class B15 and higher with a density of 1600 ÷ 2000 kg/m 3 (load-bearing parts of the walls) or lightweight concrete classes B5 ÷ B15 with a density of 1200 ÷ 1600 kg/m 3 (for heat-insulating parts of walls).
For the production of lightweight concrete, artificial porous aggregates (expanded clay, perlite, shungizite, agloporite, etc.) or natural lightweight aggregates (crushed stone from pumice, slag, tuff) are used.
When constructing non-load-bearing external walls it is also used cellular concrete(foam concrete, aerated concrete, etc.) classes B2 ÷ B5 with a density of 600 ÷ 1600 kg/m 3. Concrete walls are used in buildings of any number of floors.
V) Wooden walls used in low-rise buildings. For their construction, pine logs with a diameter of 180 ÷ 240 mm or beams with a section of 150x150 mm or 180x180 mm are used, as well as board or glue-plywood panels and panels with a thickness of 150 ÷ 200 mm.
G) walls made of non concrete materials mainly used in the construction of industrial buildings or low-rise civil buildings. Structurally, they consist of outer and inner cladding made of sheet material (steel, aluminum alloys, plastic, asbestos cement, etc.) and insulation (sandwich panels). Walls of this type are designed as load-bearing only for one-story buildings, and for larger numbers of floors - only as non-load-bearing.
3) according to a constructive solution:
a) single-layer;
b) two-layer;
c) three-layer.
The number of layers of the building’s external walls is determined based on the results of thermal engineering calculations. To comply with modern standards for heat transfer resistance in most regions of Russia, it is necessary to design three-layer external wall structures with effective insulation.
4) according to construction technology:
a) by traditional technology Hand-laid stone walls are being erected. In this case, bricks or stones are laid in rows in layers cement-sand mortar. Strength stone walls is ensured by the strength of the stone and mortar, as well as the mutual bandaging of the vertical seams. For an extra boost bearing capacity masonry (for example, for narrow walls), horizontal reinforcement is used welded mesh after 2 ÷ 5 rows.
The required thickness of stone walls is determined by thermal engineering calculation and linked with standard sizes bricks or stones. Brick walls with a thickness of 1; 1.5; 2; 2.5 and 3 bricks (250, 380, 510, 640 and 770 mm, respectively). Walls made of concrete or natural stones when laying 1 and 1.5 stones, the thickness is 390 and 490 mm, respectively.
In Fig. Figure 3.20 shows several types of solid masonry made of brick and stone blocks. In Fig. 3.21 shows the design of a three-layer brick wall 510 mm thick (for the climatic region of the Nizhny Novgorod region).
Rice. 3.20. Types of solid masonry: a – six-row brickwork; b – two-row brickwork; c – masonry from ceramic stones; d and e – masonry made of concrete or natural stones; e – masonry of cellular concrete stones with external cladding brick
The inner layer of the three-layer stone wall supports the floors and load-bearing structures of the roof. Outer and inner layers brickwork connect with each other reinforcing mesh with a vertical pitch of no more than 600 mm. The thickness of the inner layer is assumed to be 250 mm for buildings with a height of 1 ÷ 4 floors, 380 mm for buildings with a height of 5 ÷ 14 floors and 510 mm for buildings with a height of more than 14 floors.
Rice. 3.21. Three-layer stone wall:
1 – internal load-bearing layer;
2 – thermal insulation layer;
3 – air gap;
4 – outer self-supporting (cladding) layer
b) fully assembled technology used in the construction of large-panel and volumetric block buildings. In this case, the installation of individual building elements is carried out by cranes.
The external walls of large-panel buildings are made of concrete or brick panels. Panel thickness – 300, 350, 400 mm. In Fig. Figure 3.22 shows the main types of concrete panels used in civil engineering.
Rice. 3.22. Concrete panels of external walls: a – single-layer; b – two-layer; c – three-layer:
1 – structural and thermal insulation layer;
2 – protective and finishing layer;
3 – load-bearing layer;
4 – thermal insulation layer
Volume-block buildings are buildings of increased factory readiness, which are assembled from separate prefabricated block-rooms. The outer walls of such volumetric blocks can be one-, two-, or three-layer.
V) monolithic and prefabricated-monolithic construction technologies allow the construction of one-, two- and three-layer monolithic concrete walls.
Rice. 3.23. Prefabricated monolithic external walls (in plan):
a – two-layer with an outer layer of thermal insulation;
b – the same, c inner layer thermal insulation;
c – three-layer with an outer layer of thermal insulation
When using this technology, the formwork (mold) is first installed into which the concrete mixture. Single-layer walls are made of lightweight concrete with a thickness of 300 ÷ 500 mm.
Multilayer walls are made prefabricated monolithic using an outer or inner layer of stone blocks made of cellular concrete. (see Fig. 3.23).
5) by location window openings:
In Fig. 3.24 shown various options location of window openings in the external walls of buildings. Options A, b, V, G used in the design of residential and public buildings, option d– when designing industrial and public buildings, option e– for public buildings.
From considering these options, it can be seen that functional purpose building (residential, public or industrial) determines the design of its external walls and appearance generally.
One of the main requirements for external walls is the necessary fire resistance. According to the requirements of fire safety standards, load-bearing external walls must be made of fireproof materials with a fire resistance limit of at least 2 hours (stone, concrete). The use of fire-resistant load-bearing walls (for example, wooden plastered walls) with a fire resistance limit of at least 0.5 hours is allowed only in one- and two-story houses.
Rice. 3.24. Location of window openings in the external walls of buildings:
a – wall without openings;
b – wall c a small amount openings;
c – panel wall with openings;
d – load-bearing wall with reinforced partitions;
d – wall with hanging panels;
e – fully glazed wall (stained glass)
High requirements for the fire resistance of load-bearing walls are caused by their main role in the safety of the building, since the destruction of load-bearing walls in a fire causes the collapse of all structures resting on them and the building as a whole.
Non-load-bearing external walls are designed to be fireproof or difficult to burn with lower fire resistance limits (from 0.25 to 0.5 hours), since the destruction of these structures in a fire can only cause local damage to the building.
[ external house walls, technology, classification, mason, design and laying of load-bearing walls]
Fast passage:
- Temperature-shrinkage and settlement seams
- Classification of external walls
- Single- and multi-layer wall structures
- Panel concrete walls and their elements
- Design of load-bearing and self-supporting single-layer wall panels
- Three-layer concrete panels
- Methods for solving the main problems of designing walls in concrete panel structures
- Vertical joints and connections between external wall panels and internal ones
- Heat and insulating ability of joints, types of joints
- Compositional and decorative features panel walls
The designs of external walls are extremely varied; they are determined construction system buildings, the material of the walls and their static function.
General requirements and classification of structures
Fig. 2. Expansion joints
Fig. 3. Details of expansion joints in brick and panel buildings
Temperature shrinkage seams arranged to avoid the formation of cracks and distortions caused by the concentration of forces from the effects of variable temperatures and shrinkage of the material (masonry, monolithic or prefabricated concrete structures and etc.). Temperature-shrinkage joints cut through the structures of only the ground part of the building. The distances between temperature-shrinkable seams are determined in accordance with climatic conditions and physical and mechanical properties wall materials. For external walls made of clay brick on mortar grade M50 and more, the distance between temperature-shrinkable joints of 40-100 m is accepted according to SNiP “Stone and reinforced stone structures”, for external walls made of concrete panels 75-150 m according to VSN32-77, Gosgrazhdanstroy “Instructions for the design of structures of panel residential buildings " Moreover, the shortest distances refer to the most severe climatic conditions.
In buildings with longitudinal load-bearing walls, seams are arranged in the area adjacent to transverse walls or partitions; in buildings with transverse load-bearing walls, seams are often arranged in the form of two paired walls. The smallest seam width is 20 mm. Seams must be protected from blowing, freezing and through leaks using metal expansion joints, sealing, and insulating liners. Examples of design solutions for temperature-shrinkage joints in brick and panel walls are given in Fig. 3.
Sedimentary seams should be provided in places where there are sharp changes in the number of storeys of the building (sedimentary joints of the first type), as well as in case of significant uneven deformations of the base along the length of the building, caused by the specific geological structure of the base (sedimentary joints of the second type). Settlement seams of the first type are prescribed to compensate for differences in vertical deformations of ground structures of the high and low parts of the building, and therefore they are arranged similarly to temperature-shrinkable ones only in ground structures. The design of the seam in frameless buildings provides for the installation of a sliding seam in the zone of support of the floor of the low-rise part of the building on the walls of the multi-storey one, in frame buildings - hinged support of the crossbars of the low-rise part on the columns of the high-rise part. Sedimentary joints of the second type cut the building to its entire height - from the ridge to the base of the foundation. Such joints in frameless buildings are constructed in the form of paired transverse walls, and in framed buildings - paired frames. The nominal width of settlement joints of the first and second types is 20 mm. Features of the design of earthquake-resistant buildings, as well as buildings built on subsidence, undermined and permafrost soils, are discussed in a separate section.
Fig. 4. External wall views
External wall structures classified according to the following characteristics:
- the static function of the wall, determined by its role in the structural system of the building;
- materials and construction technology shared by the building’s construction system;
- constructive solution - in the form of a single-layer or layered enclosing structure.
According to the static function, they distinguish between load-bearing, self-supporting or non-load-bearing wall structures (Fig. 4).D
Bearers walls, in addition to the vertical load from their own mass, transfer to the foundations loads from adjacent structures: floors, partitions, roofs, etc.
Self-supporting walls take vertical load only from their own mass (including the load from balconies, bay windows, parapets and other wall elements) and transfer it to the foundations directly or through plinth panels, rand beams, grillage or other structures.
Table 1. Structures and external walls and their application1 - brick; 2 - small block; 3, 4 - insulation and air gap; 5 - lightweight concrete; 6 - autoclaved cellular concrete; 7 - structural heavy or light concrete; 8 - log; 9 - caulk; 10 - beam; eleven - wooden frame; 12 - vapor barrier; 13 - airtight layer; 14 - sheathing made of boards, waterproof plywood, chipboard or others; 15 - sheathing made of inorganic sheet materials; 16 - metal or asbestos-cement frame; 17 - ventilated air layer
External walls can be single-layer or layered designs. Single-layer walls built from panels, concrete or stone blocks, monolithic concrete, stone, brick, wooden logs or beams. In layered walls, various functions are assigned to various materials. Strength functions are provided by concrete, stone, wood; durability features - concrete, stone, wood or sheet material(aluminum alloys, enameled steel, asbestos cement, etc.); thermal insulation functions - effective insulation ( mineral wool slabs, fiberboard, expanded polystyrene, etc.); vapor barrier functions - rolled materials(pasting roofing felt, foil, etc.), dense concrete or mastics; decorative functions - various facing materials. An air gap may be included in the number of layers of such a building envelope. Closed - to increase its resistance to heat transfer, ventilated - to protect the room from radiation overheating or to reduce deformations of the outer facing wall.
Single- and multi-layer wall structures can be made fully assembled or using traditional technology.
The main types of external wall structures and their areas of application are given in table. 1.
Assigning a static function outer wall, the choice of materials and structures is carried out taking into account the requirements of SNiP " Fire regulations design of buildings and structures." According to these standards, load-bearing walls, as a rule, must be fireproof. The use of fire-resistant load-bearing walls (for example, wooden plastered walls) with a fire resistance limit of at least 0.5 hours is allowed only in one or two-story buildings. The fire resistance limit of fireproof wall structures must be at least 2 hours, and therefore they must be made of stone or concrete materials. High requirements for the fire resistance of load-bearing walls, as well as columns and pillars, are due to their role in the safety of a building or structure. Fire damage to vertical load-bearing structures can lead to the collapse of all structures resting on them and the building as a whole.
Non-load-bearing external walls are designed to be fireproof or fire-resistant with significantly lower fire resistance limits (0.25-0.5 hours), since the destruction of these structures from exposure to fire leads only to local damage to the building.
Fireproof non-load-bearing external walls should be used in residential buildings above 9 floors; with fewer floors, the use of fire-resistant structures is allowed.
The thickness of the external walls is selected according to the largest of the values obtained as a result of static and thermal calculations, and is assigned in accordance with the design and thermal characteristics of the enclosing structure.
In prefabricated concrete housing construction, the calculated thickness of the outer wall is linked to the nearest larger value from the unified range of outer wall thicknesses adopted in the centralized production of molding equipment: 250, 300, 350, 400 mm for panel buildings and 300, 400, 500 mm for large-block buildings.
The calculated thickness of stone walls is coordinated with the dimensions of the brick or stone and is taken equal to the nearest greater structural thickness obtained during masonry. With brick dimensions of 250X120X65 or 250X X 120x88 mm (modular brick), the thickness of the solid masonry walls is 1; 1 1/2; 2; 2 1/2 and 3 bricks (including 10 mm vertical joints between individual stones) are 250, 380, 510, 640 and 770 mm.
The structural thickness of a wall made of sawn stone or lightweight concrete small blocks, the standardized dimensions of which are 390X190X188 mm, when laid in one stone is 390 and in 1/2 g - 490 mm.
The thickness of walls made of non-concrete materials with effective insulation materials in some cases, more is accepted than that obtained from the thermal engineering calculation due to design requirements: an increase in the size of the wall section may be necessary to ensure reliable insulation of joints and interfaces with the filling of openings.
The design of walls is based on the comprehensive use of the properties of the materials used and solves the problem of creating the required level of strength, stability, durability, insulation and architectural and decorative qualities.
