Mansky excavation completed

The work to cut through the rocky foothills of the Sayan Mountains was executed by a Lovat TBM.

An SK spokesman said, "Construction of the new Mansky tunnel began in 2005. The preparation phase lasted for the first two years. A service and drainage gallery was driven in 2007-2010. The driving of the new 2464.8m-long tunnel began in October 2011. The tunnelling was carried out under complex geological conditions, in the rocks with a strength ranging from f=16 to f=20 on the Protodyakonov scale."

The TBM was driving about 10m a day and about 200m a month on average. Despite the challenging conditions, the connection was made with high precision and no deviations from the design route were recorded.

The engineers are prepared to have the new tunnel commissioned in June 2014. A non-ballasted track, utility lines, and contact network were yet to be put in place as Tunnels went to press. Also still to be completed were the railway approaches to the tunnel, and installation of the permanent lining in the connections of the tunnel to the gallery.

The spokesman added, "The New Mansky Tunnel is of strategic importance for expanding railway traffic along the southern leg of the Krasnoyarsk Railway. Building a new tunnel next to the old one in the Mezhdurechensk - Tayshet section is an important part of the OJSC RZD program aimed at providing a double-truck route and increasing the throughput capacity of the southern leg of the railway line."