ONE OF THE MOST COMPLICATED TUNNEL EXCAVATIONS ON THE BIG CIRCLE METRO LINE IS COMPLETED

A double-track tunnel is driven between the Pechatniki and Nagatinsky Zaton stations

The work related to construction of a double-track tunnel in the east of the Big Circle Line (BCL) of the metro was performed underneath the rivers crossing the capital city, and in close proximity to the existing subway station. That was announced by Andrey Bochkarev, Deputy Mayor of Moscow on Urban Planning and Construction.

Mosinzhproekt Engineering Holding is the managing company to construct new lines and stations of the Moscow Metro.

“The ‘Victoria’ tunnel-boring machine of 10 meters in diameter, facing quite constraint conditions, drove a double-track tunnel of about 1690 meters long between the to-be-constructed Pechatniki and Nagatinsky Zaton stations at the eastern section of the BCL under construction”, said Andrey Bochkarev.

According to the Head of Moscow Complex of Urban Planning Policy and Construction, the adjacent structures, soils and the ground surface were monitored around the clock throughout the line route.

“At the outset of its route, ‘Victoria’ had to manage the technical zone of the existing metro in close proximity to the Pechatniki station on the Lyublinsko-Dmitrovskaya Line, and pass through underneath the collector embracing the subterranean river Nishchenka”, said Andrey Bochkarev.

Yuri Kravtsov, General Director of Mosinzhproekt JSC, added that the tunnel-driving was complicated by unstable soils deposited along the tunnel route underneath the Nagatinsky Backwater and the Moskva River watercourse, and ranging from the water-saturated sands to the high-plastic loams and clays with the layers of sandy pebble soils.

“The work was performed at the depth of up to 30 meters, and owing to the complicated hydro-geology, approximately in the middle of the route, the cutting tool of the TBM was replaced at a purposefully equipped site”, specified Yuri Kravtsov.

According to the Holding head, after that, the tunnel-boring machine worked at the depth of 11 to 16 meters underneath the watercourse of Nagatinsky Backwater, and further passed about half a kilometer.

Prior to this tunnel boring, the ‘Victoria’ TBM was used in the construction of double-track tunnels on the Nekrasovskaya metro line from the Okskaya to Nizhegorodskaya stations and on the Big Circle Line from the Tekstilshchiki to Pechatniki stations, passing in total more than 6 km of the underground Moscow routes. The machine was also employed in development of the tunnels in Sochi.

It is noteworthy, that on December 7, Vladimir Putin, President of Russia, and Sergei Sobyanin, Mayor of Moscow, launched an underground train operation at the new section comprising ten stations of the Big Circle Line.

“Lately, we have launched an underground train operation at a large section of the BCL: from the Mnyovniki to the Kakhovskaya stations. The most challenging stage of the Circle Metro Line construction, namely driving 70 tunnels, has already been completed by 99%. By the end of the year, we will complete driving of two other tunnels in the east of the line”, wrote Sergei Sobyanin in his social media account.

The construction of the Big Circle Line of the Moscow Metro is the main project of the Moscow Metro construction. Its length will exceed 70 km, and it will accommodate 31 stations, 22 of which are already servicing the passengers.