OREANDA-NEWS. The driving operations have been completed in the Mansky Railway Tunnel in Krasnoyarsk Region. It took the builders about one-and-one-half years to drive a tunnel of about 2.5 kilometers long in the rocky foothills of the Sayan Mountains. The main work tunneling operations were carried out using the Lovat-375 Tunnel Boring Machine. More than one hundred people - tunnel builders, railway builders, representatives of the regional government - witnessed the connection procedure.

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 2464.8-meters-long tunnel began in October 2011. The tunneling 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 tunnel boring machine was driving about ten meters a day and about two hundred meters a month on average. Despite the challenging tunneling conditions, connection was done with high precision and no deviations from the design route were recorded.

The builders are prepared to have the new tunnel commissioned in June 2014. A non-ballasted track, utility lines, and contact network are yet to be put in place. The builders will also have to complete the railway approaches to the tunnel and install the permanent lining in the connections of the tunnel to the gallery. A continuous passageway for maintenance personnel will be provided in the tunnel instead of safety niches.

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.