New technologies in the construction of multi-storey buildings. Geological and topographic expertise. House printed from bioplastic, Amsterdam, Holland

Despite the global economic crisis, low-rise housing construction is still one of the most dynamically developing areas. housing construction... The variety of technologies for the construction of low-rise housing makes it difficult to choose the one that is most beneficial in each specific case. Moreover, the same construction methods often appear under different names.

The height of the buildings was made from elements timber frame... The combination of German professionals with high quality materials once again demonstrates how unfavorable our local barriers are for multi-storey timber buildings. And the professionals and materials are the same as in neighboring Germany, but there is no courage and willingness to change the currently existing harsh laws. Of course, the construction of wooden multi-storey buildings also subject to many restrictions in Germany. First of all, due to concerns about the uncontrolled spread of fire in empty places and at the same time that Basic structure can be destroyed by latent fire.

The volume of one publication does not allow us to consider the full cycle of building a house from the foundation to the ridge of the roof, therefore, in this article we will limit ourselves to analyzing the options for erecting a "box" of a building. As practice shows, for a comfortable permanent residence a family of 3-4 people is quite enough at home with an area of 200 - 300 m 2. We will focus on private residential buildings of this standard size. Country palaces, like country houses designed for summer residence were not considered, although many of the technologies below are successfully applied in these so different areas of construction.

All of these problems have been analyzed as part of a comprehensive research and development study, the results of which have shown that a wooden substructure can be protected from ignition by proper coating. Thus, it could be confirmed that a high level of fire protection in Germany would also be provided for multi-storey timber frame structures. Of course, provided that a comprehensive fire prevention concept is adopted, appropriate structural remedies are provided.

Private residential buildings must meet a number of requirements, the most important of which are the strength and reliability of the structure, comfortable living conditions, high thermal insulation characteristics of the enclosing structures, and, of course, the attractive appearance of the building. Contrary to popular belief, durability is not one of the objective factors that determine the construct of the "family nest". In a rapidly changing world, the tastes, interests and simply attitude to life (and, therefore, to housing) of our children and grandchildren are strikingly different from the "concepts" of their "ancestors" construction - seems to be a rather dubious undertaking.

There are many concrete examples of the successful completion of multi-storey timber-framed buildings in Germany. last years... Modern town houses with wheelchair access. All apartments are equipped with active air exchange systems, heated floors and barrier-free access to their interior. Each building has seven residential units, one on each floor. Only in building no. 26 the spatial organization of the lower floors is different. Individual, small living quarters were created for the guests.

Except for the façade, both buildings are the same. The load carrying capacity or integrity of building components in the event of a fire must be guaranteed for at least 90 minutes. Therefore, a significant part of heat-resistant building elements must be made of non-combustible building material. For this reason, timber structures with a load-bearing function are excluded in this class, although the building law of Berlin includes multi-storey buildings made of wood, but only up to class 4 inclusive.

However, there are as many opinions as there are developers. No one dares to argue that ceramic bricks are a bad building material, and with the availability of financial resources, time and desire, they are of good quality. brick house may very well be the best way to make your dreams come true. But what if finances are limited, life circumstances force the construction to be completed as soon as possible, but, of course, not at the expense of quality? Then you should turn to frame construction technologies.

The concept includes, in addition to the technical situation, which provides free access to the building for fire brigades, the possible provision of fire water, an evacuation plan and a rescue plan, as well as technical protection of the system. The building is equipped with a reinforced concrete staircase that functions as the first escape route. Escape routes up to 14 m are much shorter than the required length as defined in the regulations. Fire-rated doors by 30 minutes far exceed the requirements of the Berlin Building Act, which only requires sealed and self-closing doors.

Unity and diversity of FRAME TECHNOLOGIES

Frame house building is a progressive construction technology, the experience of which is more than a hundred years old. It is most widely used in North America (USA and Canada). According to some estimates, in these countries, up to 80% of private low-rise housing is in houses. frame structure... Perhaps that is why in our country this technology is called "Canadian".

All utility rooms have a second escape route - at least one window to which a ladder can be placed. Fire protection of a wooden structure guarantees its covering with non-combustible materials. In conditions of hermetically sealed combustible elements of this type, according to expert estimates, there is no higher risk than in the case of massive buildings. The coating provides fire resistance was carried out using gypsum fiberboards. Fire resistance. At the same time, due to their homogeneous structure, they provide high mechanical resistance to stress.

Frame houses are being built not only overseas. They are very popular in Germany (about 30% of low-rise buildings) and other countries of Western Europe. Hence another name: "German technology". Frame house building is in great demand in Finland, whose climate is close to that of Russia, Sweden ("Finnish" and "Swedish" technologies) and Norway, which once again confirms the suitability of buildings of this type for use in various climatic zones.

In addition, their properties are very similar to wood, making them a great addition to wood structures. The individual elements of the timber structure are covered with fire-resistant panels, which cover the sealed structure for at least 60 minutes and thus protect it from fire. Safe sealing of the cover also minimizes the risk of additional ignition and fires inside the structure. In addition, the formation of decomposition products of pyrolytic wood is thus prevented.

In our country, cottages built using frame technology are usually called frame-panel or frame-panel houses, less often - frame-wooden. Despite the variety of terms, the differences between these technologies are not fundamental, but are mainly associated with production characteristics.

With some degree of convention, we can say that under the Canadian and Finnish technology usually (but not always) element-by-element construction is understood directly at the construction site, and houses built according to this scheme are called frame-panel houses. The relatively low mass of the elements from which the house is assembled, in many cases, allows you to abandon the use of heavy equipment.

Empty construction sites completely isolated mineral wool... Alternatively, the façade is made of a neighboring house under the outer layers, in this case a gypsum fiberboard having a thickness of 15 mm and an insulating stone wool board, which is also a backing plate for the external plaster.

The fire brigade can easily enter the property from the street, and the fire hydrant is in the immediate vicinity, right in front of the neighboring house. Each apartment is equipped with an automatic fire alarm and sound signaling devices directly connected to the fire department and the security company. Fire departments or other services can access the stairs by opening the door with the fire key located in the storage compartment. The basement walls, including the underground garage, were made of reinforced concrete.

German technology involves not only the manufacture of components, but also the assembly of large wall panels (with window and doorways) and roofing in an industrial enterprise. A high level of factory readiness, reaching 80-90%, and the highest possible precision in the manufacture of panels ensure the speed and quality of assembly of the house, which in this case has every reason to be called frame-panel. The significant dimensions and weight of the panels will most likely require the use of a crane.

Also, external fire walls from the side of neighboring buildings, an internal staircase, an elevator shaft and two transport panels are made of reinforced concrete. The wooden structure of the walls prevents the spread of fire. The building was constructed in a skeleton structure. While two steel supports are placed between the two outer walls of concrete as supporting elements, each of which is in one third of the outer wall... Thanks to the high degree of pre-assembly on site, a fast and trouble-free assembly process was ensured.

Looking ahead, let us say that the panels are made in accordance with an individual project, therefore, analogies with panel "Khrushchebs" in this case are completely incompetent.

Structural scheme

The basis of the wall structure, which is actually a "layer cake", is a rigid and durable frame made of specially dried (moisture not more than 18%) coniferous wood. As a rule, the frame elements are treated with special antiseptic (fungicidal) preparations, which provide them with long-term protection from rot and mold, as well as fire retardants (fireproofing) that increase the fire resistance of wood. Some manufacturers instead of traditional wooden beams use more modern materials for example, beams and I-beams made of LVL (Laminated Veneer Lumber) - a high-strength building material, which is actually a multi-layer glued veneer.

Strengthening the structure of the building is provided by a reinforced concrete staircase and two building cores. Thus, it was possible to offer residents the opportunity individual design apartments on separate floors prepared on request. Conclusion: Timber structures also make sense in the case of urban homes.

The architects have proven that their construction project in Berlin has proven that timber structure can also be used for multi-storey buildings, while providing fire protection to the same extent as massive reinforced concrete or masonry structures, provided they are planned and used appropriately. preventive measures. The wooden structure additionally served as a seal, covering the space built in this part of the city. Project: Architects Kaden Klingbeil, Berlin.

From the outside, the wall frame is sheathed OSB boards(Oriented Strand Board) - a durable moisture-resistant material made of pressed oriented strand, non-combustible cement-bonded particle boards (CSP) or boards "Aquapanel Outside" (Knauf). The slabs are covered with a vapor-permeable windproof membrane on top of which an external finish is arranged.

Focus: energy saving, acoustic comfort and impressive facades. External walls are one of the most important parts of the house - they carry loads from the roof and floors to the foundations, insulate the interior of the house from cold, atmospheric factors and external noise. In the case of stratified walls, the end result consists of a warming layer. It is important that the insulating material has as little heat transfer coefficient λ as possible. Complete insulation systems. Insulation material must be selected for the heating method.

Today, manufacturers offer complete thermal insulation systems, consisting of insulation materials, plaster and the necessary construction chemicals. The choice of the entire system is a guarantee that adequate wall insulation is maintained and that the facade is protected at all times. An ecological approach. Maintaining an energy efficient home is also environmentally friendly - the less energy we use to heat the building, the less fuel we use. However, energy efficiency is not the only parameter of the green approach.

From the inside, the frame is sewn up with gypsum plasterboard (gypsum plasterboard) or OSB boards, on which they arrange interior decoration (wallpaper, painting, tiles, decorative plasters etc. etc.). Materials such as lining or blockhouse successfully combine the functions of interior cladding and decoration; in this case, there is no need to use GCR. The space between the outer and inner skin of the frame is filled with effective thermal insulation material which is most often used as fire-resistant plates made of mineral (basalt or glass) fiber. An integral element of frame technology is a vapor barrier, which is located between the insulation and the inner lining. A sealed vapor barrier layer prevents moisture from the insulation and the wooden frame, therefore, the effectiveness of thermal insulation and the service life of the elements of the frame system depend on the quality of its implementation.

It also takes into account whether the material for the building walls is made from natural raw materials that are energy intensive during production and what is their subsequent disposal. The choice of wall material is the result of all criteria. Energy saving is not just brick. With a new generation of insulating materials, indoor buildings built today enable the efficiency of energy efficient or even passive buildings to be achieved. Energy efficient prefabricated houses are also being built - prefabricated ceiling walls are covered with thermal insulation and gypsum panels are added externally as a prefabricated element outside the construction site.

On the initial stage frame house building was the prerogative of the carpentry crews who erected “ canadian houses", As they say," in place. " The situation has changed in recent decades. "Sabbat" brigades, staffed by specialists from the near abroad, still do not suffer from lack of work, but a significant part frame houses now produced on industrial enterprises equipped with sufficiently modern equipment, which allows you to get a completely different level of quality.

Difficult trade-offs. The choice of the type of external walls entails not only economic, but also beneficial consequences, therefore it should be thought out in terms of energy efficiency, as well as taking into account the needs and capabilities of the investor. Fashionable facades. The outer layer of the walls builds the image of the house.

It is possible that our chosen facade material imposes a kind of wall, for example, a facade brick is associated with the need to build a three-layer wall. Brick walls... This type of exterior wall is very popular in our country. Masonry walls can be installed from various materials- aerated concrete, ceramics, silicates or clay concrete. They are characterized by high strength and thermal inertia - they store heat and slowly return it to the environment. Adequate thermal insulation of masonry walls can be achieved easily, mainly by applying an appropriate insulation thickness.

In the field of industrial production of timber frame structures, the most advanced is the MiTek technology developed by MITek Inc. USA. This technology is a comprehensive solution for computer-aided design and production of wooden building structures for various purposes.

Freemasonry technology has been used for many years, so materials for the construction of such walls are widely available, and it is also easy to find professionals who will strengthen warm walls Houses. Building brick house can be expanded over time - this is an important advantage if the house is built economically. However, the construction of masonry walls requires a lot of time and laboriousness, and the need for wet work requires technological breaks and the suspension of construction in the winter.

Skeletal walls. The most important advantage of skeletal walls is the speed of their construction - a skeletal house can live up to 3 months after its start. Although skeletal walls are not yet popular with us like bricks, it is becoming increasingly difficult to find a reliable, dedicated executive team. Due to the material of the skeletal walls - properly prepared timber - such houses are considered ecological. Wooden walls... They are usually made from logs, wooden balls, insulated with insulating material or laminated planks.

MiTek software allows you to perform as a complete calculation in the shortest possible time frame house and calculations of individual structures ( roof structures, floor beams, wall panels, formwork structures, etc.). In addition to static analysis and design of wooden trusses, the software package issues working documentation in the form of drawings of wooden elements, assembly drawings, connections, etc.

Wooden walls grow quickly and do not require technological breaks. They provide a favorable microclimate at home, are environmentally friendly, quickly warm up and accumulate heat. Building log walls requires finding a specialized, proven executive team and properly prepared timber. Since this technology is not very common in our country, it is relatively difficult to verify the correct design of wooden structures. It is also an expensive type of wall - properly dried and soaked balls are not cheap.

As well as software MiTek supplies the market with technological lines for the production of frame houses, as well as equipment for the production of individual items. The compatibility of robotic modules with the MiTek software package allows you to transfer information about the geometry of wooden structures directly from the program, which completely eliminates the likelihood of errors caused by the notorious human factor, and ensures extremely high manufacturing accuracy.

Advantages

Currently, timber frame technologies are the most preferable option for housing construction intended for permanent residence of self-sufficient and quite reasonable citizens who consider themselves to be the middle class, but at the same time are not burdened with status prejudices such as “the frame is Nif-Nif’s housing, but a real businessman must live in a brick house. "

Let us remind once again that a great many American millionaires (including Hollywood stars) live in frame-panel houses and do not have any complexities about this at all.

From the point of view of construction economics, the advantages of the "frame" are more than obvious:

very high speed of erection of the "box" of the building;
the cost of a set of materials and installation is noticeably (approximately 1.5 times) lower,
than similar indicators of a brick, log house or log house;
smooth and even internal and external surfaces eliminate the need for plastering and other wet processes, which significantly reduces the cost and accelerates the finishing of the building;
frame house many times lighter than brick or chopped, which allows the use of more economical shallow foundations *;
the useful area of the house is higher than that of analogues made of traditional materials due to the thinner walls;
a great variety of ready-made proven projects allows you to minimize the cost of the services of an architect and designer.

Some manufacturers indicate the cost of the house and the construction time without taking into account the work on the foundation. This is a completely normal marketing ploy, you just need to understand that building a house for, say, one to two weeks requires a ready-made foundation. For obvious reasons, the option with the installation of a house worth more than 1 million rubles. we do not consider cement-sand blocks.

For example, the actual timeline may look like this. First of all, you need to choose a ready-made or order an individual project that best suits your preferences. The choice of a ready-made project is not a long matter, but the creation individual project will take much more time. After that, in the workshops of the enterprise, in accordance with the approved project, the production of structural elements of the frame house begins. At the same time, zero-cycle works are carried out on the building site, after the completion of which the manufactured structural elements are delivered to the object and their installation begins on the finished foundation.

The duration of the full construction cycle depends on the complexity of the project, the chosen finishing options and many other factors, but in most cases the duration of the work ranges from two to three months to six months. It should be noted that the absence of wet processes allows the construction of the box and finishing at negative temperatures (it is advisable to complete the foundation arrangement before the onset of cold weather).

Aesthetics frame house building

From the standpoint of architecture, design and the natural desire of every developer to build a house that no one else has, frame technologies open up an unlimited field of activity. Almost any exterior finish is possible for wood, brick, wild stone, as well as plaster, siding, etc., so even houses built according to the same project can look so different that an outside observer will never think of the close relationship of these structures. Finished project- the option is very profitable, but completely optional.

Modern technologies for the design and production of frame-panel houses make it possible to realize the most daring ideas of architects. However, even in quite distant times, frame housing construction allowed creating true masterpieces of architecture. A clear confirmation of this statement can be the surviving Victorian-style American mansions, a significant part of which was built using frame-panel technology.

There are no restrictions on the choice interior decoration: wallpaper, painting, lining, ceramic tiles and different kinds panels - this is not a complete list finishing materials used in frame housing construction. At the same time, frame-panel structures are not subject to shrinkage, therefore, finishing work can be started immediately after the installation of the "box" is completed. Another advantage is that all utilities (heating, plumbing, sewerage, electrical wiring, etc.) are usually arranged inside the walls.

Exploitation

From an operational point of view, a huge advantage of modern frame houses is their high energy efficiency. A properly designed and built frame house works like a giant thermos: it perfectly retains heat, it cools extremely slowly (only a few degrees per day) even in the most severe frosts, and even in the summer heat, a comfortable temperature remains inside such a house for a long time, which provides a huge savings on air conditioning.

With proper care, a frame-panel house (again: correctly designed and correctly built from high-quality materials) will last at least half a century, and most likely much longer.

LSTK

There is another type of frame housing construction, known under the abbreviation LSTK (light steel thin-walled structures). The structure of structures erected using this technology is very reminiscent of the frame-panel houses already familiar to us, but it has one important difference: the supporting frame of the building and the rafter system are made not of wood, but of thin-walled metal profiles and thermal profiles.

These elements are usually formed from cold-rolled galvanized steel sheet with a thickness of no more than 2-3 mm. The thermal profile differs from the usual profile by the presence of perforations in the form of narrow longitudinal cuts arranged in a checkerboard pattern. The slots provide a decrease in the thermal conductivity of the profile in the transverse direction, which entails an improvement in the thermal insulation properties of the structure as a whole and excludes the formation of cold bridges.

The elements of the frame, manufactured at an industrial enterprise in accordance with the project, are delivered to the construction site, where the final assembly of the metal structures is carried out. The assembled frame is sheathed with a suitable sheet material (CBPB, CBPB, GVL, GKL, etc.), and the inner space of the wall panels is filled with an effective insulation (usually, the same mineral fiber slabs are used for this purpose).

LSTK has all the advantages of frame-panel technologies. In addition, the use of only non-combustible materials is the key to the highest possible fire safety of structures of this type.

According to some estimates, the service life of frame houses based on light metal structures can reach 50 years or more. The estimated cost of the house kit is 12-15 thousand rubles. per 1 m 2, and the cost of finished housing is up to 20 thousand rubles. for 1 m 2.

LSTK are widely used for the construction of industrial, warehouse and utility rooms, exhibition and shopping and entertainment centers, sports facilities, etc. In the private sector, the share of structures of this type is still small, but the demand for LSTK for the construction of low-rise (up to three floors) housing is growing every year. Due to their low weight and fire safety, structures based on LSTK are successfully used for superstructures of attic floors on existing buildings.

SIP-PANELS

Another technology for the rapid construction of low-rise housing is based on the use of SIP panels (from Structural Insulated Panel) as the main elements of wall and roof structures, which are sandwich panels with a polystyrene core with a thickness of 100 to 200 mm, sheathed on both sides with OSB-3 plates. A calibrated wooden bar, which, when assembling the house, enters the groove of the adjacent panel, it ensures the strength of the connection and excludes the formation of cold bridges. All SIP layers are glued together with polyurethane glue under high pressure on special equipment and are distinguished by high strength, as well as heat and sound insulation characteristics.

Houses made of SIP panels are often referred to as “ Canadian houses", And the construction technology itself is" Canadian ", but, unlike frame-panel" Canadian "houses, SIP-technology is frameless. All loads are absorbed by the paneling and connecting wooden beams, which play the role of a load-bearing frame. Expanded polystyrene also contributes to its share of "strength", which resists compressive stress very well. The panels are manufactured under industrial conditions, which ensures high quality and accuracy of geometric dimensions.

AdvantagesSIP-technologies are obvious:

the cost of a house kit is 30-40% lower than that of a brick house;
the use of an inexpensive shallow foundation;
high rates of construction;
heating costs are several times lower than those of similar brick or concrete houses;
no shrinkage;
smooth walls simplify and speed up finishing work;
high strength and seismic resistance of the structure;
a huge selection of modern finishing materials for both interior and exterior decoration;
design service life up to 80 years (some manufacturers even claim 100 years).

Potential developers are usually worried about two questions: "Are SIP panels fire hazardous, and how are they doing with environmental friendliness?" From point of view fire safety a house made of SIP panels is not too different from a log or squared counterpart. In the production of OSB-3 boards, special additives are used that impede combustion.

The environmental aspect also does not cause any particular concerns, but only if high-quality materials with certificates of conformity are used for the manufacture of panels. An indirect confirmation of the safety of this technology can be the fact that in the USA multi-apartment residential buildings (up to 9 floors), hospitals, schools etc.

CELLULAR CONCRETE

An artificial material based on mineral binders and silica aggregate containing a large amount (up to 85%) of air pores (cells) 1-1.5 mm in size is called aerated concrete. In fact, this is a whole group of materials with similar properties, but slightly different production technology. Without going into details, let's say that there are two types of aerated concrete: aerated concrete and aerated concrete (also known as aerated concrete, autoclaved aerated concrete).

The composition of foam concrete includes cement, finely ground quartz sand, water and foaming agents, which give this material a cellular structure. The prepared mixture enters the molds, where the material hardens. Foam concrete sets under normal conditions, which allows it to be produced directly at the construction site.

The technology for the production of autoclaved aerated concrete is much more complicated. A thoroughly mixed mortar, prepared from Portland cement, quicklime, sand, water and aluminum powder, is poured into molds, in which the aerated concrete sets initially for several hours. The pores are formed by bubbles of hydrogen, which is released by a chemical reaction between lime and aluminum. After standing, the blocks are cut with strings into a commercial size and fed into an autoclave, where they are kept for several hours at a temperature of 180-200 ° C and a pressure of 10-12 kg / cm 2. Autoclaving allows you to get porous building material with very specific characteristics. It should be noted that the need to use complex and bulky equipment completely excludes the possibility of handicraft production of aerated concrete blocks, so they arrive at the construction site only in finished form.

Due to the presence of numerous pores, cellular concrete has excellent thermal insulation characteristics and high vapor permeability. It does not contain chemical additives and does not emit any harmful compounds. The density of this material can range from 300 to 1200 kg / m 3.

With an increase in density, the strength of aerated concrete increases, but the thermal insulation characteristics decrease. For this reason, blocks of the D300 brand (the number indicates the density) are used almost exclusively as thermal insulation and are unsuitable for construction load-bearing walls, and for the construction of low-rise (up to three floors) housing are most often used aerated concrete blocks D400-D500, which have an optimal balance of strength and thermal insulation properties.

Autoclaved aerated concrete is somewhat more expensive, but with the same density, its strength characteristics are about two times higher than that of foam concrete. In addition, aerated concrete blocks usually benefit from geometric parameters. Suffice it to say that the leading manufacturers of gas silicate blocks maintain the dimensions of their products with an accuracy of tenths of a millimeter. Such blocks can be laid on special glue with a seam thickness of only 1-2 mm. The fact is that the thermal conductivity of the masonry mortar is many times higher than the thermal conductivity of aerated concrete, therefore, the thinner the seam, the lower the level of heat loss.

The advantages of aerated concrete:

high thermal insulation characteristics, allowing for a reasonable wall thickness to do without additional insulation;

high vapor permeability: a gas silicate house "breathes";

non-combustible and fire-resistant material that does not emit toxic chemical compounds when heated;

an extensive range of standard sizes, the presence of arcuate blocks, lintels, beams, floor elements, etc.;

environmentally friendly material made from natural ingredients;

a variety of finished projects;

Features of construction from aerated concrete

Aerated concrete, like the vast majority of traditional building materials, needs protection from the destructive effects of atmospheric factors. The most economical and fast way finishing smooth masonry from aerated concrete blocks is the use of light thin-layer plaster. The plaster must have hydrophobic properties, and its vapor permeability must not be lower than that of aerated concrete. During construction country cottages is very popular facing masonry facing brick... In this case, a ventilation gap must be arranged between the aerated concrete base and the brick cladding, which ensures the removal of water vapor, which diffuses from the room through the wall throughout the entire heating period.

All materials in this group are characterized by low bending strength. To minimize deformation loads and prevent cracking necessary condition is the device monolithic foundation... The most reliable is the foundation in the form of a monolithic reinforced concrete slab, but options such as a monolithic strip foundation on a sand cushion or a columnar foundation tied with a monolithic reinforced concrete belt are also quite suitable. The final choice in favor of one or another design can be made only after conducting geological surveys on the building site.

PORCED CERAMICS

Large-format porous ceramic blocks are a relatively new product for our country, although this material has been used in Western Europe for almost half a century, and now a significant part of residential buildings in the EU are built from ceramic blocks.

The most important advantage of ceramic blocks is the low coefficient of thermal conductivity (0.14-0.26 W / m 2 0 С), which makes it possible to erect single-layer walls from this material without insulation, which fully meet the requirements of building heat engineering. Due to the low thermal conductivity, due to the presence of voids and numerous pores in the body of this material, it received its second name: "warm ceramics". In addition, porous ceramics, which, by the way, is the closest relative of classic ceramic bricks, is an environmentally friendly product and has a capillary structure that allows the wall to "breathe", which creates a favorable indoor climate and provides an optimal humidity regime. wall structures... Products of this group are manufactured in accordance with GOST 530-2007 “Ceramic bricks and stones. General technical conditions ".

The largest ceramic block with a size of 14.3 NF (510x250x219 mm) replaces 14 normal format bricks (NF), but due to its high voidness, it remains light in weight and easy to use in the masonry technique. This makes it possible to increase the rate of masonry several times, and the low weight of the wall structures built from such blocks reduces the load on the foundation, which makes it possible to simplify its structure, and, consequently, the cost.

Advantages of "warm" ceramics:

high rates of laying due to large (in comparison with ordinary brick) the size of the porous blocks;
saving mortar (groove-ridge connection of large-format blocks makes it possible to do without the use of mortar in vertical seams);
high strength grade (M100-150) makes it possible to use porous ceramic blocks for laying load-bearing walls of multi-storey residential buildings;
meeting the requirements of modern standards for heat conservation without additional insulation (single-layer wall construction);
a smooth masonry surface reduces the consumption of plaster, and also simplifies and speeds up the implementation finishing works;
long service life comparable to that of traditional ceramic bricks.

In fact, only autoclaved aerated concrete can compete with "warm" ceramics, since, as we have already said, only these two materials allow the construction of homogeneous walls that do not need additional thermal insulation. At the same time, the average density of porous ceramics products is higher, and the thermal insulation characteristics, respectively, are lower than that of gas silicate, therefore, a wall made of "warm" ceramics (all other things being equal) should be 20-30% thicker. This means that the width strip foundation heavy concrete should be slightly larger. In addition, porous ceramic blocks are about a third more expensive than aerated concrete blocks.

Does this mean that porous ceramics are worse than autoclaved aerated concrete? Not at all! It is just necessary to consider the full set of characteristics of the building material, paying special attention to those properties that play a dominant role in each specific case.

Everyone chooses for himself!

Almost from the beginning of time, man has been striving upward. Tower of Babel, Egyptian and South American pyramids, Cologne Cathedral, Empire State Building, Moscow City, Burj Dubai - all these are links in one endless chain linking millennia of development high-rise construction... And each new height seemed to contemporaries the ultimate - only the sky is higher.

Today it may also seem that the limit of "storming the heavens" has almost been reached: some of the skyscrapers have already come close to the kilometer mark. However, progress is unstoppable. What have we achieved, what is in store for us in the near future, and what miracles are we yet to see?

Yesterday and today

It is believed that modern high-rise construction began for a prosaic reason - due to the lack of land in rapidly growing cities. This is partly true - for example, the limitedness of Manhattan Island really made New York developers "pull" the buildings up. But this does not explain the real "race for heights" that unfolded since the end of the 20th century in completely free territories, like the Arabian Desert.

In fact, the answer is simple: people started building skyscrapers because they learned how to do it. High-quality steel, concrete and a safe elevator are the true creators of the high-rise boom. In particular, reinforced concrete and the development of technologies for working with it contributed to the growth of the number of storeys.

Despite the fact that concrete work itself began to be used in ancient times (for example, the Great Wall of China was largely created using technology monolithic construction), concrete showed its amazing abilities most fully when creating skyscrapers. The breakthrough was the invention metal frame- he made it possible to obtain structures of almost any height.

The “vertical race” was accelerated by the invention of the removable reusable formwork. It was invented in post-war Germany, destroyed by bombing. It was necessary to quickly and efficiently build almost the entire infrastructure "from scratch". Neither time, nor materials, nor manpower were sorely lacking. Therefore, according to legend, German businessman and engineer Georg Mayer-Keller decided to collect ready-made wooden boards metal fasteners to quickly move them from one object to another. The idea turned out to be so successful that now it is difficult to imagine monolithic construction of any number of storeys without such a collapsible formwork.

Over the past decades, modern formwork systems have gone very far from their ancestor. The panel formwork system adopted today everywhere in high-rise construction includes frame panels, retaining elements and fasteners. Frame panels are the basis of the system. They are assembled from a rigid metal frame (steel or aluminum) and a formwork board, usually plywood. Thanks to design features prefabricated formwork allows you to fill any surface - vertical, horizontal, curved, rounded and even inclined.

“In many ways, the properties of the formwork depend on the strength and quality of the shield material: it must withstand enormous loads - up to 8 tons of poured concrete per square meter - and be resistant to the aggressive thermal and chemical effects of hardening concrete. Film faced birch plywood surpasses even steel in terms of weight-strength ratio, and a special phenolic film coating provides reliable protection against harmful factors. Therefore, the formwork made from such panels successfully allows the implementation of almost any architectural ideas, ”says Andrey Kobets, Product Development Manager at SVEZA, the world leader in the production of birch plywood.

The higher the building, the stronger it is. But in other way, Construction Materials should be easier. Otherwise, the skyscraper may simply not be able to support its own enormous weight. Therefore, the "high-altitude race" required the combined efforts of chemists, metallurgists and architects. For example, the reinforcement of concrete with steel made it possible to avoid the main contradiction in the use of any analogs of stone - the lack of sufficient tensile strength in the latter. In low-rise buildings, this is not essential, but starting from 4–5 floors, for the stability of the structure, you have to thicken the walls. This is unacceptable in modern construction. Iron helped to get around the problem: it has a coefficient of thermal expansion approximately equal to concrete (in other words, it reacts equally to heat and cold). Thus, the elastic metal takes on the tensile force, allowing builders to move upward without fear.

The technology of prestressed reinforced concrete has even more "advanced" the construction site. The method consists in the fact that high-strength steel reinforcement is tensioned with a special device before placing the concrete mixture. When the concrete sets, the pretensioning force is transferred to the curing material, compressing it. Thus, partly or completely, tensile stresses from loading are eliminated.

“The prestressing allows you to significantly reduce the weight of the structure and increase its strength,” says Denis Portaev, head of the prestressing department of the industrial and construction holding GK PromStroyKontrakt. “Thanks to this technology, the distance between the bearing columns can be increased up to two times, the thickness of the slabs can be reduced by up to 20% and the concrete consumption can be reduced by 25%.”

It is interesting that one of the first developers of the method (along with European companies) was the Soviet scientist Viktor Mikhailov.

Above the sky

Today, over 2,600 skyscrapers have been built in the world, a third of which (862) were built in China (including Hong Kong and Macau). The rest are located in the USA - 665, Japan - 163, UAE - 146 and other states, and every year more and more countries join the "heavenly club". However, although high-rise construction has long ceased to be exotic, each skyscraper is a unique building. Therefore, the classification of high-rise buildings is rather arbitrary. Nevertheless, it is, since there are a number of "unified" design solutions that serve as a guide for professionals.

Such solutions are updated and approved at regular meetings of international independent communities of engineers and architects - IABCE (International Association for Bridge and Structural Engineering), ASCE (American Society of Civil Engineers) and CIB (International Council for Research and Innovation in Building and Construction). The last organization - CIB - in 1976 at its symposium adopted the classification of skyscrapers by their height in meters, which is now generally accepted. Buildings below 30 m were classified as structures increased number of storeys; up to 50, 75 and 100 meters - respectively to the I, II and III categories of high-rise buildings, and over 100 meters - to high-rise buildings.

The latter group, in turn, is also divided in height with a step of 100 meters. Today, there are about 10 buildings higher than 400 meters in the world, from 300 to 400 meters - a little more than 20, from 200 to 300 meters - about 100 meters. Most of the skyscrapers are in the range from 100 to 200 meters, and it is impossible to count them exactly - the pace of construction is too high.

Regardless of the architectural delights, all modern skyscrapers are united by a common structure: as a rule, this tower is more or less rounded. The unity is due to two main factors. First, a building of this height should not interfere with the natural light of its lower neighbors. Secondly, the higher the height, the stronger the wind loads (the upper floors of high-rise buildings swing quite noticeably for the inhabitants in strong winds). To reduce their impact, it is better to choose the optimal aerodynamic shape of the building - a pyramid, cylinder or prism. Moreover, the base of the high-rise should always be somewhat wider than the top.

With all the obvious advantages of high-altitude pyramids (stability and aerodynamic stability), they are not erected due to the complexity and consumption of materials. But there are plenty of cylinders and prisms all over the world - you can recall the famous Burj Dubai (UAE) or the capital's skyscrapers "Moscow City".

Another example of the use of cylinders in architecture is the "North Tower" of the "Moscow City" complex. The tower body was built using a monolithic technology, and then completed with a solid glass facade. “The choice of building technology depends on the architectural design of the building,” says Alexander Globa, engineer of the production and technical department. construction company"INRI". - And the main difficulty lies in the correct combination of methods. The North Tower was originally designed correctly, architecturally and technologically, which is why it is so interesting. "

What is the coming day for us?

The future, as you know, begins today. And the nearest line of high-rise construction - a kilometer - is about to be crossed. There is very little left to the cherished mark - the recently opened Burj Dubai has exceeded 800 meters. But height is not at all the main trend, and it does not determine the immediate prospects of skyscrapers.

There are two main trends that will prevail in the next 10–20 years - architectural uniqueness and environmental friendliness of projects.

The first trend, at first, does not seem special - after all, as already mentioned, any skyscraper is unique. However, if you look at the skyscrapers even 10 years ago, you can see that there are no special architectural delights in them. As a rule, these are just towers of glass and concrete, at best, with unusual spiers.

Only in recent years have there been buildings that really stand out for their original design. And it was they who set the tone for the next race - this time for beauty. For example, you can highlight the Kuwaiti skyscraper Al Hamra Firdous ("Al-Hamra Firdous"). Despite its rather ordinary, by today's standards, height - “only” 412 meters - it has become a world attraction, resembling, rather, a modern art installation. With its dynamic, complex shape, the skyscraper resembles a moving human figure in national Arab clothing. This effect was achieved thanks to the use of modern construction technologies.

“The complex silhouette of the building,” says Andrey Kobets (SVEZA), “was obtained using the monolithic construction method. In this case, the effective spiral shape of the outer wall was made possible by a removable formwork with birch plywood panels (during the construction, among other things, SVEZA plywood was used). This project has become unique today - for the first time in the world, a skyscraper was built exclusively using the monolithic method. Suffice it to say that the construction of Al Hamra Firdous took more than 500 thousand tons of cement - this is a real man-made rock! "

The second global trend - "green" - is also actively developing today. It arose not so much in the wake of the ecology fashion as as a response to the discomfort that a person experiences in a super-urbanized environment. A way out of the situation can be the organization of the habitat as close as possible to the natural one, inside the "steel caves" of megacities. Such a bioclimatic environment is the immediate goal of architects and designers.

“Higher and higher and higher…” - modern architecture has been following this slogan for more than a century. Thanks to the monolithic construction technology, the standard glass towers are being replaced by man-made mountains covered with forests, interiors and technology are changing, but one thing remains unchanged: the challenge to earth's gravity. Fortunately, the latest materials and technologies are constantly pushing the horizons of construction.