Enlargement of the Fachinger Tunnel Successfully Completed
Between Diez and Fachingen, Porr is upgrading the 426 m long, double-track Fachingen Tunnel, which dates back to the 19th century. On behalf of Deutsche Bahn, Porr is working in a consortium with Feldhaus Bergbau GmbH & Co. KG and Heinz Schnorpfeil Bau GmbH. The tunnel cross-section has to be widened in order to guarantee the prescribed clearance gauge. In addition, the track spacing will be increased to 4 m. The enlargement is being carried out using the tunnel-in-tunnel method. On November 21, 2024, the tunnel enlargement system (TES) “Nora” breached the breakthrough wall of the Fachinger Tunnel. This milestone marked the end of the 380-metre-long conventional widening of the 160-year-old tunnel during ongoing rail operations.
The prevailing rock properties presented the tunnelling team with particular challenges. In order to cope with the changing geology of clay shale and keratophyre throughout the entire excavated cross-section, occasional blasting to loosen the rock was necessary during the excavation work. The excavated material fell next to the TES and was then removed by conveyor equipment. During the entire construction work, rail traffic continued to run safely under the protection of an enclosure on a newly laid track in the middle of the tunnel.