U-Bahn München, U 2-Ost Baulos 1, Josephsburg

The altogether 3,700 m long tunnel tubes are being driven by a shield tunnelling machine (diameter 7.35 m). The geology comprises alternating beds of water-bearing gravel, impermeable marl and water-bearing sand, as a result, the drive has to be undertaken under compressed air. A partition wall is situated at the end of the advance shield (length 7.28 m), which separates the excavation chamber under compressed air from the remainder of the tunnel. As a result, no crew members need to work in the compressed air area during standard operations. The cutting arm with a longitudinal cutting head, which has a nozzle attachment by means of which a membrane like sealing of the face can be accomplished without any loss of time, is housed in the chamber. In addition, it also has 11 injection channels for advance grouting through the shield jacket, a shotcrete manipulator for additional supporting of the face and a conveyor belt, which transfers the material into a time lock. The partition wall accommodates the time lock for the material and a man lock. The cutting arm is controlled from the man lock so that the geological and hydrological situation can constantly be controlled. The tunnel is being lined with 1.5 m wide reinforced concrete segments.

Country: Germany
Region: Bayern
Tunnel utilization: Traffic
Type of utilization: Underground, urban and rapid transit
Client: Landeshauptstadt München, U-Bahn-Referat
Main construction method: Trenchless
Type of excavation: Shield machine (SM)
Lining: Reinforced concrete segments
No. of tubes: 2
Tunnel total length: 2250 m, incl. Stations and branch-off-structure
Cross-section: 7.35 m
Contract Volume: 115 mill. DM
Opening: end of 1996