Tunnel System No. 5 on Adler - "Alpika-Service" Mountain Resort Route

Tunnel System Number Five is located between the 39.9th and 42.7th

kilometer marks of the Olympic route, next to Esto-Sadok Station.

Construction began in the 2nd quarter of 2009 with completion in the 3rd quarter of 2012.

The system consists of three tunnels: a motorway tunnel (1,372 m), a railway tunnel (2,910 m), and a service gallery (2,867 m).

The motorway tunnel was driven using mining machines. The tunneling operations were started in October 2009. To expedite the work, the tunnel cap was driven from four faces simultaneously (from the northern and southern tunnel entries and also from auxiliary faces that were initiated through the service gallery). The upper (cap) parts of the motorway tunnel were connected in May 2011. The driving of the bottom (stross) part of the tunnel section is scheduled for completion by the end of 2011.

The motorway tunnel was driven under challenging conditions, and the work was done in weak rocks (black carbonaceous shales, green porphyrites, and quaternary deposits) that made it harder to advance the mining equipment. Specialists had to use customized methods such Jet Grouting, Symmetrix, and the like for shoring up the unstable soils in order to ensure work safety and also to rule out rock inrush and failure. The Jet Grouting technology uses a custom-built drilling rig to drill horizontal boreholes that are 12 to 15-meters long over the entire face cross-section. Cement mortar, which is injected under high pressure into the boreholes, hardens to make the rock more stable, and, as a result, the mining machine can work under normal conditions in the stabilized rock.

Lovat RME 167 SE Tunnel Boring Machine (3.9-m diameter) was used for gallery tunneling. The work started in July 2009 from the southern tunnel entry and was completed in June 2010.

The railway tunnel of Tunnel System Number Five was driven using Herrenknecht-10690 Tunnel Boring Machine (10.6-m diameter). The work on this tunnel was started in April 2010 and was completed in February 2011.

Please visit the web site www.skmost2014.com for updated information on
Adler "Alpika-Service" Mountain Resort route.