Tunnelling was carried out in difficult hydrogeological conditions

The length of tunnelling on the Big Circle Line (BCL) sections to be launched this year is 23.9 km. This was informed by Andrey Bochkarev, Deputy Mayor of Moscow on Urban Planning and Construction. Mosinzhproekt Engineering Holding is the operator of the Moscow Metro Development Program.

“In total, 23.9 km of tunnels were tunnelled in the section from Mnyovniki to Kakhovskaya under reconstruction, with double-track tunnelling in the western section carried out by giant tunnel boring machines, and the south-western and southern stations were linked by single-track tunnels,” noted Andrey Bochkarev.

According to him, 9 tunnel boring machines (TBMs) were used for tunneling work on all three sections.

For his part, Yuri Kravtsov, General Director of Mosinzhproekt JSC, specified that 10 meter diameter TBMs, Liliya and Nadezhda, were used for driving in the west of the BCL, 6 meter diameter TBMs, Rosa and Natalia, were working in the south section, and Maria, Polina, Galina, Evgeniya, and Daria were used for constructing single-track tunnels in the south-west of the Big Circle Line.

“Tunnelling was carried out in difficult hydrogeological conditions in these sections, the TBMs passed under residential development and key road routes in several areas of the capital, as well as railway tracks quite uneventful,” explained Yuri Kravtsov. However, according to him, the builders coped with the task in a decent manner thanks to round-the-clock monitoring of the state of facilities on the surface and the safety of the existing underground facilities in the construction zone.

Recall that the technical launch of the southern section of the Big Circle Line from the Prospekt Vernadskogo station to the Kakhovskaya station has taken place today with the participation of Mayor of Moscow Sergei Sobyanin.

The construction of the BCL is the main megaproject of modern Russian underground railway system construction. It will be the longest underground circle in the world, with a length of 70 km, hosting 31 stations, exceeding 57-km Circle Line of the Beijing Metro.