27 March в 07:02

Sergei Sobyanin: Moscow metro engineers develop new method for assembling tunnel boring machines

Photo by: Press Service of the Moscow Mayor and Moscow Government

They reduced the total length of the tunnel boring machine “Olga” that workers use in the left running tunnel from 106 to 70 meters. The machine itself was divided into sections, which were lowered into the excavation pit in stages as work progressed.

Moscow metro engineers have developed a unique method for assembling tunnel boring machines, Sergei Sobyanin shared on his MAX channel.

“Metro construction is always a labor-intensive process. Still, our engineers were challenged with the issue as they tackled the section between the Novomoskovskaya and Sosenki stations on the Troitskaya line,” Sergei Sobyanin said.

The tunnels had to be dug under highly constrained conditions. An excavation pit needs to be at least 100 meters wide to facilitate the assembly of a tunnel boring machine. This pit, however, was extremely small: just 30 by 25 meters.

Engineers reduced the total length of the tunnel boring machine “Olga” that workers use in the left running tunnel from 106 to 70 meters. The machine itself was divided into sections, which were lowered into the excavation pit in stages as work progressed. The machine moved on site along the walls, rather than in a straight line, snaking its way forward.

“Tatiana” (another tunnel boring machine) will be dealing with a more complex challenge. This machine will be used to create the right running tunnel. It will have an even narrower space to operate in as some of “Olga”’s systems are already in place there.

Engineers devised a solution to this extremely difficult situation: an unconventional method of assembling the machine using a conveyor system that collects excavated material into a compact storage unit. The soil will be lifted to the surface using a grab crane.

This solution leaves enough room in the excavation pit for workers to move about safely. This one-of-a-kind approach is complex to implement; it requires a high degree of precision and experience working as a team.

Sosenki will be built at the intersection of the Kaluga Highway and Projected Passage No. 7032, near the village bearing the same name. Construction is scheduled to be completed in 2029.