The Chinese are gradually conquering the world market with their own brands: Chinese cars, Chinese household appliances - all this can be used without fear for your life and money. But a new direction has emerged - Chinese houses. 30 floors in 15 days… isn't it a bit fast to build?

000:00:00 The tamping of the earth and the erection of the foundation are not included in the construction timing. The foundation has the code F-D3000-1 and is nominally not part of the T30, the time for its construction is taken into account separately - this is such a "trick"

Tim Skorenko

The achievement of Chinese civil engineers from the company Broad Sustainable Building back in 2012 swept across the World Wide Web like a steamroller. Sensational footage and an equally amazing video of the construction of the 30-story T30 hotel in 360 hours - the timer was ticking in the bottom corner of the video - aroused much more doubt and criticism than admiration. Nevertheless, the buildings built by BSB look solid - both inside and out. When advertising its products, the company emphasizes the highest seismic resistance, which is much higher than that of other similar structures. Will the T30 withstand a magnitude nine earthquake? God forbid that he did not have to experience such stress at all. But for some reason I believe that it will survive.

So the speed

No matter how you look at it, there are a lot of advantages in BSB developments. Moreover, most of them (the aforementioned seismic resistance, energy efficiency, service life built into the design, etc.) remain in the shadows. On the surface - insane speed. From the moment the first slab was placed on the prepared construction site to the making of the last bed in the suite on the top floor of the T30 hotel, it took only 360 hours, that is, 15 days. What makes it possible to maintain such a pace?

The Chinese "fast-build" T30 meets all the technical requirements for five-star hotels. There will also be a swimming pool: it will be built a little later.

First: prefabricated structure. Of course, BSB does not build houses in the sense that we are accustomed to invest in the concept of "construction". The company rather assembles them from prefabricated standard parts. For the most part, these are steel plates and columns with diagonal struts, on which the ceilings are installed. Plates have different shape and are made up of standard square segments; the width of each slab is 3.9 m, there are three standards along the length - 15.6; 11.7 and 7.8 m. For one trip, a truck from the factory can bring two or three plates and all related fastening materials, 36 segments go to one floor. The lower part of the slab is the ceiling ready for finishing, the upper one, respectively, is the floor. On average, seven to eight deliveries provide a complete supply of all materials for the assembly of one floor. Side panels with pre-installed thermal insulation and cable ducts are installed in the same way. All parts are standard, and their assembly is greatly simplified thanks to the pins and grooves: workers do not need to align or measure anything: in fact, they “blindly” assemble the building, working literally with wrenches. The error is only ±2 mm, according to the developers. After installing the floor slabs on the floor, the workers simply screw on all the details of the “body kit” and immediately stretch out the elements of the electrical network, air ducts and other communications.

000:00:00. The tamping of the earth and the erection of the foundation are not included in the construction timing. The foundation has the code F-D3000−1 and is nominally not part of the T30, the time for its construction is taken into account separately - this is such a "trick".

005:45:22. For the first few hours, the construction goes a little slower than usual, because the work is not typical - fixing the initial panels and supports on the foundation. In the future, the assembly is significantly standardized and accelerated.

056:28:10. The central “tower” with an area of four segments (7.8 x 7.8 m) overtakes the surrounding part of T30 in terms of construction pace, serves as an analogue of scaffolding and supports the tower crane, which “grows” along with the building.

Second: parallel work. An ordinary building is built in stages: first, a frame is erected, then the next type of work is performed, the next, and so on. BSB works differently. When the upper floors are not yet in sight, the lower ones are already glazed and the interior decoration is being installed; Electricity was installed there and furniture was even partially delivered. Finishing, as already mentioned, is also prefabricated: fastenings are provided on the supporting columns for heaters, and for heating structures, and so on and so forth. A large and complex constructor means that it can be assembled in almost any order - except perhaps from the roof.

And thirdly, a number of works are not mentioned in the construction dates. The countdown starts from the moment the first support is placed on the foundation. The time of tamping the soil and pouring the foundation itself is not taken into account. The Chinese do it pretty quickly - but still a few days are added, whatever one may say. The timer stops with the completion of the last floor, but the final work by this moment “crawls” to about 2/3 of the building: the rest of the interior is being finished after the fact. Here are some small advertising tricks. Also, the man-hours spent on the manufacture of parts are not taken into account. Naturally, their conveyor, factory production greatly speeds up the process, but it also takes more than 0 minutes 0 hours.

Nevertheless, the technical documentation has a clever explanation for all this. BSB buildings are nominally divided into three elements. In particular, the hotel, built in 360 hours, according to the documentation, consists of three independent structures - T30 (the hotel itself), F-JT240 (lobby) and F-D3000-1 (foundation with parking). Such a presentation allows us to say without deceit that the T30 was built in 15 days - without taking into account the rest of the structures.

However, BSB also announces the full term for the hotel to be put into operation - from the appearance of the first bulldozer on the site to the cutting of the red ribbon. It was 48 days. Not bad for a high-level hotel (classification - five stars) with 358 rooms! The hotel is located, by the way, in a very romantic place - on the shores of Dongting Lake in Hunan Province.

Technological advantages

But there are things more important than speed. The developers highlight a range of know-how that makes BSB buildings far superior to the competition. These are increased seismic resistance, excellent energy efficiency, a high degree of indoor air purification, durability, savings and the use of environmentally friendly building materials.

The company took up the development of earthquake-resistant structures after the tragic Sichuan earthquake of 2008 - this is where the story of Broad Sustainable Building began. After hundreds of hours of research and testing, the current structure was developed: ultra-light steel structures combining vertical and diagonal supports. The China Academy of Structural Research conducted two serious tests of BSB buildings: replicas of a 7-story building (1:4 scale) and a 30-story hotel (1:10 scale) were built, after which they were “shaken” to simulate earthquakes of various magnitudes . This extremely expensive study showed that BSB buildings are at least three times more sustainable than their traditional competitors (and in some indicators - 10 - 12).

Another "chip" is energy efficiency. About 30 different energy-saving technologies are used in BSB buildings. Some are quite simple - a competent system of thermal insulation of walls and roofs (the thickness of heat panels is 15 - 35 cm versus 3 - 5 in ordinary buildings) and original double-glazed windows that turn the building into an analogue of a large sleeping bag, LED lamps. There are also more elegant ideas: elevators allow you to generate energy when going down; savings are also achieved through the technology of water treatment and its reuse in the sewerage system. The original BSB technology saves energy thanks to the system of heat exchange between the external and internal environment.

In general, air purification is the main activity of the parent company BSB - Broad Group. BSB installs air pollution control membranes in every room in every building. Depending on the purpose of the room, monitoring is carried out according to the PM0.3, PM2.5 or PM10 method (where the number indicates the diameter - in micrometers - of air pollutants that the detector's filter does not pass through). For cleaning, a three-stage “super filtration” method is used. The first stage is a coarse filter, the second is the company's know-how, an electrostatic filter that traps up to 98% of harmful impurities, the third is a classic HEPA filter. This whole system works like a big modern vacuum cleaner.

A significant advantage of the technique is its low price: standard factory elements, the minimum cost of transporting materials and construction. At the same time, the construction site is surprisingly clean, construction debris is practically absent. By the way, such a quick construction of the T30 had another goal besides advertising: the terms of reference included the need to be in time before the start of the rainy season.

Comparison of the parameters of a BSB hotel and an ordinary five-star hotel. BSB leads many different comparison tables showing the benefits of their technology. As a “competitor” of T30, an “average” 5-star hotel is accepted (regardless of the climate zone).

What does the future offer

Of course, the technologies demonstrated by BSB are the future. It has not yet arrived, and not a year or two will pass before its arrival, but the Chinese have great confidence in their abilities. To date (in two years), they have built only four buildings - each with something different from the previous one - mainly to test the methodology.

The Broad name really shot on March 6, 2010 at EXPO 2010 in Shanghai, where CPO16's six-story pavilion was erected in just six hours in front of an astonished audience. In July, the 15-story New Ark Hotel in Changsha (Hunan Province) was erected in 160 hours, and in November, the Broad Group pavilion in Cancun (Mexico) was erected at the UN climate change conference in eight days. T30, built in December 2011, has become the largest and most successful BSB project. The hotel was built by a little over 200 workers (not counting the employees of the factory producing structural elements) and a single tower crane. With the expansion of conveyor production and the company itself, BSB promises to build 50 buildings per month by 2014.

Sky City skyscraper. When designing Sky City, the "national Chinese idea" was taken into account: the destruction of class inequality. Apartments and workplaces in a giant skyscraper are designed for people of various incomes. In terms of overall height, Sky City will be slightly lower than the famous Burj Khalifa in Dubai - "only" 666 meters. At the base, it will be a square with a side of 140.4 meters. It is assumed that the production of parts of the skyscraper will take 6 months, another two months - its erection on the spot. It is better not to compare the pace of the construction of the Moscow City business center with the pace declared by the Chinese ...

BSB engineers are constantly improving the design. The versatility of their power circuit allows you to build almost any building and structure from BSB panels and supports. And so the Chinese are not going to stop there. At the end of 2010, they announced their intention to implement the mega-ambitious Sky City project, a 200-story earthquake-resistant skyscraper that could simultaneously live and work for more than 100,000 people. Sketches and technical documentation of Sky City most of all resemble shots from a futuristic movie like The Fifth Element. One of the social goals of Sky City (and typical mega-skyscrapers like it), if successful, is to allow people to live and work in the same building, thus solving the problems of traffic and overcrowding. The dimensions of the skyscraper will make it possible to spread the living space and workplaces at the proper distance from each other.

Considering the working capacity of the Chinese and the speed of their technical development over the past 15 years, you can believe in hundreds of houses built according to the T30 principle, and in the titanic Sky City. Although ... It is much more pleasant to live in a city that pleases with its architectural individuality, and not with standard boxes. Even if it is energy efficient and earthquake resistant.

An apartment building differs from an individual one in that it has several separate exits to a land or apartment plot. Also, houses are recognized as multi-apartment houses, the height of which exceeds 3 floors, including underground, basement, attic, etc.

Classification of the number of storeys of buildings

There is the following classification of residential buildings, which differ in the number of floors:

Low-rise (1 - 3). Most often, they include individual residential buildings. The height of the building, as a rule, does not exceed 12 meters;
Mid-rise (3-5). The floor height of 15 meters is a standard five-story building;
Elevated number of storeys (6-10). The building is 30 meters high;
Multi-storey (10 - 25):

High-rise. From (25 - 30).

The number of storeys of a building is considered solely by the number of floors above ground. When calculating the number of storeys, not only the value from floor to ceiling is taken into account, but also the value of inter-storey ceilings.

Apartment buildings. Number of floors and height of buildings

In modern projects, the "golden mean" is the height of one floor of 2.8-3.3 m.

Only highly qualified specialists are engaged in the construction of multi-storey buildings, since this business requires not only high costs, but also has many nuances.

There are the following types of multi-storey buildings:

Panel. Belongs to a series of budget. It has a high construction speed, but poor heat and sound insulation. The maximum number of storeys is about 25, depending on the design. In a residential area, the height from floor to ceiling is 2.5 - 2.8 m, depending on the size of the panels.
Brick. The construction speed is quite low, because the construction is costly. Thermal and sound insulation indicators are much higher than panel ones. The optimal possible number of floors is 10. The average height of each is 2.8 - 3 m.
Monolithic. These buildings are quite diverse, because everything rests on the bearing capacity of concrete. They have high seismic resistance. To improve heat and sound insulation during construction, brickwork can be used. Allows you to build about 160 floors. Height from floor to ceiling 3 - 3.3 m.

How to get a permit for an IHS? What does a builder need to know?

Permitting authorities follow the order of development and agree on documents for individual housing construction according to RSN 70-88. Thanks to them, not only the accuracy of building up the site is determined, but also the layout of the dwelling and auxiliary buildings. This project needs to be well thought out, because what is not displayed in the plan will be recognized as an unauthorized structure and must be demolished or re-approved.

Without permission, that is, before the approval of the plan and receipt of documents, work should not begin, otherwise serious problems may arise. In order to find out exactly what documents are required to start building, you should read the "Code of rules for the design and construction of SP 11-III-99".

In 2010, SNiPs were recognized as binding rules. They regulate activities in the field of urban planning, as well as engineering, design and construction.

In order to obtain permission, you need to contact the BTI or the architectural department of the city to provide:

application for a building permit;
documents establishing the right to use the site;
certificate of field determination of boundaries, placement of buildings, etc.;
cadastral plan of the site;
House project.

Once issued, the permit is valid for 10 years.

Individual housing construction

The number of storeys of an individual residential building is calculated based on the number of residents and personal preferences. The minimum height of a room according to SNiP is 2.5 m. If the height does not meet these parameters and turns out to be lower, then this room will be considered unsuitable for habitation.

How many floors can be built on the site? On an individual plot, it is permissible to build a three-story house with a height of about 9 meters. In this case, both underground and above-ground premises are taken into account.

What can be erected in the garden?

Many are interested in the question of what can be built and how many floors can be built independently on garden plot? In addition to outbuildings, it is possible to build a dwelling on the garden plot that is not suitable for registration. When erecting buildings on a garden plot, SNiP should be followed.

Collapse of a 15-storey building of the LG-600 series in Leningrad (St. Petersburg)

On February 27, 1979, a 15-story large-panel residential building of the LG-600 series completely collapsed in Leningrad.

The structural scheme of the building consists of transverse load-bearing walls with a "narrow" pitch of 3.2 m. The building has a plan size of 18x18 m and a height of 44 m. The internal load-bearing walls are 14 cm thick and made of heavy concrete class B15. Exterior walls are hinged aerated concrete class B5, based on the floor consoles.

The ceilings are solid, 14 cm thick, made of heavy concrete class B15, supported on three sides. Initially, reinforced concrete piles were driven for the entire house, however, when tying it on the ground, it had to be deployed, so a gravel-sand mixture was backfilled between the piles and then a reinforced concrete slab 800 mm thick was concreted.

During the formation, metal fixing pins were laid in the internal load-bearing walls, which makes it possible to carry out the forced installation of floor slabs, which were laid on three sides in a fixed position. These pins were used during the installation of the first houses of the LG-600 series, but then they were rarely used.

The LG-600 series was developed for 5- and 9-storey large-panel buildings, and for 16-storey houses of this series, the bearing capacity of internal load-bearing walls 14 cm thick turned out to be insufficient, so it was decided to build houses with a height of 15 floors (Fig. 25).

Rice. 25. Large-panel 15-storey building of LG-600 series

External aerated concrete walls of horizontal cutting were hung on the floor consoles. Three-meter aerated concrete inserts-piers were installed along the A axis, which rested through the solution on the aerated concrete waist panel, and at the top were separated from it with USM-50 mastic, gernite gaskets and antiseptic tow and sealed with mortar only at the edges. But at the construction site, mortar was laid instead of gernite gaskets. Thus, the aerated concrete panels turned from hinged into load-bearing ones, the load from them was transferred to the ground floor console.

Before the accident, 23 large-panel houses of the LG-600 series were assembled (Fig. 26). The installation of the 21st house was stopped when the sixth floor was being built, due to the poor quality of the installation. In the 22nd house, props were installed, since the structural scheme of the house was violated in it - the outer walls made of curtain walls became load-bearing, i.e. the same thing happened as in the collapsed 23rd house.

Rice. 26. Large-panel residential buildings N 21 (6 floors installed) and house N 22, standing on props

When examining the 22nd house, supported by logs, starting from the foundation, attention was drawn to the exit from the plane of the compressed aerated concrete panels, the destruction of the floor cantilever on the short side and a number of other structural damages, which caused the deformation and collapse of the 23rd large-panel house ( Fig. 27).

Rice. 27. View of the collapse of a 15-storey large-panel building in Leningrad

In table. 8 shows the installation time of the floors of the house and the outside temperature. The installation of the house began on January 19, 1979 and was completed on February 24 - in almost one month. During this period, the negative temperature of the outside air was constantly maintained, on February 26, 1979, the first day there was zero temperature, the mortar in the seams and joints began to thaw, and the concrete began to crack.

The next day, the thawing of the mortar in the seams and joints of the house continued, the cracking intensified: due to the redistribution of the load, the concrete cracked, the floor consoles burst. In the evening, the house collapsed, almost vertically.

On fig. 28 shows that the fragments of the collapsed building were evenly distributed in plan. Some displacement of the blockage to axis A confirms the opinion that the collapse began from this axis due to a change in the structural scheme of the house.

Rice. 28. Collapse of a large-panel building

Table 8. Temperature conditions during the installation of the building

On fig. 29 shows the concrete and reinforcement of structures after the collapse of the house: reinforcement and broken concrete - separately.

Products for this house were manufactured in December 1978 during the period severe frosts. The panels were taken out of the warm workshop immediately for installation. And, as you know, with a drop in the temperature of wetted concrete below -30 ° C, temperature deformations change abnormally, and the rate of destruction compared to standard freezing (up to -20 ° C) increases by about ten times.

Rice. 29. Concrete and reinforcement of structures after the collapse of the building

The anomaly lies in the sharp, spasmodic expansion of concrete, i.e. in decreasing its thermal coefficient of linear expansion. The consequence of this is the occurrence of stress concentrations: along the thickness of the structure - between concrete layers parallel to the cooling front; between concrete and reinforcement; between reinforced concrete floors and transverse walls during construction.

On fig. 30, 31 shows the quality of manufacturing and installation of large-panel structures. On fig. 32 - collapse of a large-panel 15-storey residential building. There were no victims during the collapse of the house, since the track and noises were heard in the house loudly enough and for a long time, thereby warning of possible collapses.

Rice. 30. Horizontal joint between floor panels and interior wall

Rice. 31. Panel support inner wall on the floor slab (metal linings are visible)

Rice. 32. Reinforced concrete foundation slab after clearing the rubble

Conclusion. The reasons for the collapse of the building were: thawing of thick horizontal seams on all floors of the house; the transformation of the outer panels from hinged to load-bearing and, as a result, the transfer of the load from all the outer walls of fifteen floors to the console of the floor slab, which burst, and the inner load-bearing wall panel resting on it turned, pulling the reinforced concrete panel located on the short side of the floor and pushed through the slab overlap. The inner wall panel of the first floor, continuing to turn after the collapsing ceiling, contributed to the deformation of the structures located along the A axis, followed by the loss of stability of the entire building.

After the collapse of the 23rd 15-storey large-panel residential building in Leningrad, the 22nd 15-storey large-panel residential building continued to stand, supported by wooden studs from the foundation to the 6th floor, which to some extent increased the stability of the building. There have been various proposals to strengthen the building, including the installation of metal columns around its perimeter. However, it was decided to dismantle the 22nd house - no one wanted to take risks.

Although, from our point of view, the house could have been saved by performing the following work: by removing the mortar from the horizontal seams of the outer wall panels, for which it was necessary to cut aerated concrete blocks and reinforce the crushed floor slabs. The strengthening of the slabs was due to the fact that the load on them from the concrete wall panels was transferred parallel to the working reinforcement, i.e. the cover didn't actually work. There was a lot of work to be done in an emergency large-panel building. The decision to dismantle the house required the installation of a second tower crane - one insured the installers, and the second crane dismantled the house structures.

Thus, two 15-story large-panel residential buildings were not built in Leningrad due to violations of the quality of manufacturing products, the quality and accuracy of the installation of the house, the quality of design solutions and regulatory documents.