The price of delay in rationing high-rise buildings

Professionals say that it will be more expensive to build a 50-storey house than two 25-storey ones. More materials, financial and time costs are required to erect a conditional "running meter" of a building. We found out why this happens using the example of the Olympic residential complex. This is a residential complex consisting of three 37-storey high-rises (130 m), which is being built in Yekaterinburg by Atomstroykompleks company.

Valery Garanin, the chief architect of the project, shared his experience in coordinating special technical conditions, and Dmitry Khvatov, the head of the construction site, spoke about the engineering features of the project.

- Valery, how was the approval of the STU for the Olympic residential complex?

- Our company has experience in the construction of high-rise buildings with 30-40 floors, however, project approvals took place differently when MGSM was used as a regulatory act in our region, where all the norms are clearly spelled out. While working on the Olympic residential complex project, we encountered the unpredictability of the STU approval process. There is an opinion that an architect is a creative profession that implies a subjective approach, whereas designers work with precise norms and algorithms. In fact, the expert designer's approach turned out to be no less subjective.

We submitted two projects of high–rise buildings for examination at the same time, and if all the approvals went through quickly enough with the first one, then with the second one, the Olympic residential complex, they took a little longer.It was necessary to develop a STU not only for fire, but also for the architectural and construction part, in which, firstly, we were charged with including seismic measures, which led to a 30-35% increase in the cost of the project. And secondly, for the first time we were faced with the need to coordinate the project not only in red, but also in yellow lines.

- But now you have gained experience that will help you build other high-rise buildings!

- You can't enter the same river twice. The trouble is that the process of obtaining a STU for each facility is individual, and due to the fact that we do not have uniform norms and rules for high-rise construction, we go through it every time as in the first one. It is especially unpleasant that if, after passing the examination, you decide to make changes to the project, then you have to go all the way from the very beginning. If you get to a new expert, it's not a fact that he won't make additional requirements for the project.

- Dmitry, the fire department did not raise any questions during the examination. Tell us, what kind of engineering solutions did they mean?

- Roughly speaking, the implemented scheme is comparable to what it would be like if we put two 22-storey buildings on top of each other. The entire building is divided into two compartments: from the first to the 20th floor and from the 21st to the last. Technical solutions are duplicated in both compartments and work independently. Depending on the location of the fire, the system of the corresponding compartment is activated.

- What is the difference between the construction process of a high-rise facility compared to a typical one?

- The differences in construction are noticeable already at the stage of laying the foundation. The height of the foundation plate in the Olympic residential complex was 2 meters. The volume of poured concrete does not differ from what we pour at typical facilities, but its class is twice as high. The density of wall reinforcement is also twice as high: in a standard house it averages 60 kg per cubic meter of concrete, in a high–rise facility it is 110-120 kg per cubic meter. The thickness of the plates in a typical facility is 200 mm, and here it is 250 mm. Columns with a cross-section 1.5-2 times larger are also used – 700x700 and 800x800 compared to 400x400, typical for typical construction. In addition to the difference in materials, high–rise construction involves additional measures, such as laying a safety net.

These features affect the pace of construction: we are building the Olympic residential complex at a rate of three floors per month, whereas we are building five or six floors at a typical facility. Thus, it takes about twice as much time and materials to build a high-rise facility as it does to build a typical building.

- What measures do you take in order to reduce time costs during construction?

- We use special equipment and technologies that facilitate the work of builders and thereby increase efficiency. These are, for example, a stationary concrete pump, a wind protection kit, and special electric cars that roll out the formwork tables. We also plan to use an unusual solution for the city – to install construction lifts not outside, but inside the building, in the elevator shaft. This will make it possible not to reduce the speed of facade work and free up crane time, as well as delay the installation of elevators so as not to operate elevator equipment until the house is put into operation.

- What would you recommend to developers who are just preparing to build 100+ buildings?

- You need to assess your strengths and capabilities very soberly. Due to the lack of clearly regulated requirements and standards for the design and construction of buildings over 75 meters, there is a need to develop and coordinate STU. If you are doing this for the first time, it is unlikely that you will be able to accurately calculate the cost and timing of construction. In this case, I recommend that you study the recommendations of the professional community as much as possible, which can be obtained, among other things, on the portal and on the 100+Forum Russia.