At the Big Circle Line station under construction, construction of the middle tunnel has begun. A tubing machine has been operating in the area of the future central hall since May 25. Alexey Kreis, deputy head of the first section of SMU-8, told how many days and cast iron rings are left until the work is completed.
The shaft of mine No. 946 goes 65 meters underground. From here a trapezoidal approach adit stretches for almost a kilometer. The underground path arcs around the distillation tunnels between Maryina Roshcha and Butyrskaya - they are only a meter deeper. You can hear the trains going by below.
The tunneling crews of section No. 1 are working around the clock. The middle tunnel of the future station is being built 25 meters below the adit level. There is a TU-4GP tube layer working there. When the correspondent visited the mine, 16 cast iron lining rings had already been installed.
The launch of the machine was preceded by large-scale preparations. First, a branch was made from the adit - a near-trunk yard with a diameter of 7.5 meters. Then, for another three months, using jackhammers, we passed through a blind vertical shaft.
“We walked through strong limestone with layers of dolomite, marl with layers of clay, and crossed a couple of aquifers,” recalls Alexey Kreis. – Having reached the level of the future Sheremetyevskaya, we built a chamber for the installation of a tubing layer.
The middle hall of the three-bay pylon station will accommodate 199 full rings. It is planned to be built in just over a year. By this time, shields with a diameter of six meters will transit the right and left pilot tunnels. Subsequently, they will be expanded to eight and a half meters.
Meanwhile, at the adit level, they continue to build an interchange from the Bolshaya Koltsevaya to the Lyublinsko-Dmitrovskaya line. Here, between the two stations, a spacious approach corridor has already been built - made of 56 cast-iron rings with a diameter of 9.5 meters.
Three human walkways will be built from it, behind which there will be stairs to the center of the Maryina Roshcha hall. One of them has already passed 24 meters. Now it is being “dressed” in metal for subsequent concreting. The second one has just begun, the first frames are being installed. The start of work on the third is still ahead.
– From the same corridor in the future we will make another one with a diameter of 11.5 meters, where a machine room will be located for four escalator belts of small inclined speed, sums up the deputy head of the site.