Dzhubga – Lazarevskoe - Sochi

The works were carried out in the constrained conditions of mountainous district, on minimally possible building sites, at big level difference, in super-tough rocky soil. Special difficulties were caused by fracturing of rocky formations, local ruptures, intercalation of rocky and inconsistent soils.

Cementation of boreholes for successful drilling and difficult selection of drilling tools for the borehole stabilization were applied.

Construction was conducted in unusual for the HDD method manner that means “from itself’, by means of pipe thruster. On the sections where the topography of the district didn't allow to hang out a pipeline lash a pipe thrusting was carried out section by section with the welding of bottom pipe on the racks directly ahead of the pushing device.

Drilling tool produced by the Australian company TRANSCO MFG AUSTRALIA PTY.LTD was applied for the overcoming of rocky formations.

Innovative combination of two methods (HDD and pipe thrusting), the most difficult technology of tamping (individual for each site), the HDD technology improvement, invention and introduction of drilling tools and technical devices directly on site – has put the work within this project in a special row. Successful completion of the works has shown that the method of horizontal directional drilling which always had serious geological restrictions thanks to modern approaches became applicable in the conditions of super-sophisticated soils.