Gap Closing of Underground U5: Completion of Track Construction in Central Berlin

SSF puts Berlin Undergound with track design between Brandenburger Tor and Rotes Rathaus into motion

The new underground U5 in Berlin is taking shape: the completion of track constructions between the existing stations Brandenburger Tor and Museumsinsel as well as between Museumsinsel and Berliner Rathaus present another milestone for the planned gap closing of U5 in central Berlin.


At station Museumsinsel the excavation by mining technique is completed; tracks in this section will only be installed after structural works in the course of this year. Works at underground stations Unter den Linden and Rotes Rathaus have already further progressed: construction of both stations designed by SSF will be completed at the middle or end of this year.


Track construction design starting at station Brandenburger Tor comprises the construction of track troughs on individual bearings as heavy mass-spring systems with vibration dampers of 8 Hertz. The superstructure is ballasted. To increase the life cycle of the ballast, a sub ballast mat is installed on the track trough. Starting at the track switching system including station Berliner Rathaus, the vibration reduction (dampening measure 15 Hertz) is achieved by a ballasted track system on sub ballast mat.


SSF, as part of an engineering joint venture, designs the three stations (Berliner Rathaus, Museumsinsel, Unter den Linden), a track switching system, a storage yard as well as the track construction. The newly built section has a length of 2.2 kilometres and closes the gap between the existing tunnels at Berliner Rathaus and station Brandenburger Tor (currently U55). The new underground line U5 directly connects Berlin’s city centre to the Central Station and the resident areas in the east part of the city. The new U5 is planned to start operation in 2021.


Photo Credits: Antonio Reetz-Graudenz