Reconstruction of the Second Dzhebsky Tunnel in the Dzheb – Shchetinkino stage of the Abakan – Taishet section of the Krasnoyarsk Railway.
Beginning of reconstruction - 2014; completion - 2015.
The tunnel is 660.86 meters long.
Scope of Operations:
Installation of a continuous welded track in the tunnel;
Installation of variable stiffness sections on the approaches using LVT half-sleepers in rubber sleeves, with shock-absorbing pads.
Installation of communications, automatic control and remote control networks, a contact network, ventilation and smoke removal systems in the tunnel escape routes (two connections to the existing tunnel);
Building new tunnel entries;
Installation of new seamless tunnel lining with anti-seismic joints and waterproofing;
Reconstruction of the existing drainage systems and outside drainage structures;
Reconstruction of paramilitary guard facilities.
The tunnel reworking is done by drilling and blasting. The Liebherr R944 Litronik demolition is used as the head machine for the mechanized removal of the existing tunnel lining. The Axera T11-215 Self-Propelled Drilling Rig having two boom-mounted high-performance Atlas Сорсо COP Hydraulic Rock Drills and a suspended telescopic platform for safe work at an altitude is used for the drilling and blasting work.
The tunnel reconstruction is carried out after the jet grouting was used to consolidate the space behind the lining. Cement mortar injection ensures stability of loose soil and rules out rock collapse.
The reconstructed Second Dzhebsky Tunnel will pass up to 65 pairs of trains thus significantly increasing the throughput capacity of the railway line.