Autostrada rebuilt this important facility for the capital in 9 months - including design. A new monolithic tunnel was built at the accident site, the tunnel frame of the existing tunnel was strengthened, new rails were laid, and engineering networks were restored.

The tunnel restoration project was developed by 3 groups of engineers from the Avtostrada project institute. To realize this object, our team had to try many different technologies. In particular, in solving the problem of flooding the distillation tunnel, which is actually in the river. Before starting the construction of a new tunnel and strengthening parts of the existing one, Autostrada specialists developed a water reduction system and performed chemical stabilization of the soil. Under pressure, a special chemical - a two-component polymer - was pumped into the ground through the frame of the tunnel. This made it possible to displace water and increase the shear strength of the soil. After the introduction of the polymer, the soil was fixed with microcement. Microdispersed cement reduced the amount of water in water-saturated soil and increased its bearing capacity. In order to avoid leakage of water-saturated soil from under the tray of the tunnel frame, Jet grouting was used - a method of fixing the rock of a new generation, which allows to significantly simplify the construction process on unstable and waterlogged soils. The essence of this technology consists in drilling a well into which a cementing solution is fed under high pressure, which helps to mix the soil and concrete to obtain a concrete column, in which reinforcing elements are added to increase strength.
In order to minimize the risks of flooding in the future, we used a special repairable waterproofing system made of PVC membrane during the construction of the new tunnel. In case of damage, such waterproofing can be easily restored even after the facility is put into operation.
The parts of the existing tunnel, which are adjacent to the restored one from the side of the "Lybidska" and "Demiivska" stations, were strengthened with a reinforced concrete "shirt" by the method of dry and wet shotcrete - spraying concrete on the surface of the tunnel frame.
In general, the construction of this tunnel included almost all methods of construction of the subway, except for the tunnel complex.
In Ukraine, this kind of object was implemented for the first time.
Before opening the restored section to full traffic for passenger trains, the tunnel underwent test run-in and commissioning works for a month. Specialists checked the serviceability of traffic safety systems, the condition of the new track, and also tested the new tunnel at different speeds of electric trains - from 25 to 80 km/h.
It is important that thanks to the optimization of project solutions and rational technologies, Autostrada saved Kyiv 62 million UAH, performing work 20% cheaper than the initial cost of the project - 445.49 million UAH.
The estimated cost of the entire complex of works amounted to UAH 383 million, of which UAH 20 million is the maintenance of the customer, and UAH 10 million is compensation for the MAFs that were located at the construction site. The actual cost of works by the Autostrada company is UAH 353 million.
It was important for us to complete this facility as soon as possible, because the subway is daily comfort and safety for thousands of passengers.