Baustellenexkursion Verlängerung der Stadtbahnlinie U5 in Frankfurt a. M.

Thanks to the kind invitation of Dipl.-Ing. Gerrit Hofmeister (PORR GmbH & Co. KGaA), the Institute of Geotechnics was able to visit the „Extension of the U5 Europaviertel light rail line“ project in Frankfurt with sixteen Master's students on 22 February 2024. They were able to see one of the deepest excavation pits in Frankfurt (length around 180 m, width up to 35 m, depth up to 24 m), the tunnel and the ramp structure.

During the site excursion, Dipl.-Ing. Thomas Beckmann, Head of Technology (PORR GmbH & Co. KGaA), introduced the students to the demanding construction processes in this deep excavation pit and the complexity of the planning and the accompanying geotechnical measurements.

When descending into the excavation pit, the massive reinforced concrete stiffeners in three stiffening layers, which can bear loads of up to 25 MN, could be seen. The tunnel lining showed the successful installation of the tubes along the entire length of the project. Particularly noteworthy were the 1.2 m thick diaphragm walls, which safely bear the enormous load of the deep excavation pit. Along the diaphragm walls, the influence of limestone beds in the Frankfurt clay can also be clearly recognised in the form of striking bulges.

The Institute of Geotechnics would like to thank PORR GmbH & Co. KGaA for the invitation, to Mr. Thomas Beckmann for the very informative guided tour and to our employee, Mr. Alexander Kochnev, for organising this exciting excursion.