On behalf of Deutsche Bahn, the consortium PORR GmbH & Co. KGaA, FELDHAUS Bergbau GmbH & Co. KG, Heinz Schnorpfeil Bau GmbH is carrying out the tunnel renovation. Between the start of construction in January and late autumn 2023, all the preparatory work was completed, such as creating the construction site facilities, dismantling the tunnel portals, installing the slope stabilisation, constructing the stop walls as well as installing the tunnel widening systems.
This was followed by a few well-earned moments of pause. The construction site at the western portal of the Fachinger Tunnel kicked off in October 2023 with the tunnel naming ceremony and the symbolic tapping of the tunnel. The tunnel will be driven from here in the direction of Diez. The ARGE companies and the Deutsche Bahn project management team introduced the tunnel patron to her honorary position. A statue of St Barbara, who has been the patron saint of miners since the Middle Ages, was then blessed by the church. The extent to which the neighbouring communities are involved in the tunnel renovation was also demonstrated during the Barbara celebration on 4 December, during which the miners prayed for the protection of their patron saint. During the prayer service, the local male choral society sang and presented the miners' song in honour of the miners present. The local association treated the tunnellers to delicious home-baked bread.
Widening the tunnel tubes using cyclical tunnelling
The demolition and widening work is being carried out using the tunnel-in-tunnel method while the railway is in operation. For this purpose, 46-metre-long, rail-bound tunnel expansion systems (TAS) weighing around 270 tonnes were lifted into place. Rail traffic continues to run safely on a newly laid track in the centre of the existing tube under the protection of an enclosure during the entire construction work. Powerful equipment such as chisels, drills and shotcrete manipulators are mounted on the outside of the TAS. Nora and Tilly also have space for the required materials. A tunnelling cycle begins with the demolition of the existing shell, consisting of masonry and back packing. The face is then opened and the rock material is broken off. Chisels are predominantly used for this, with controlled blasting in isolated cases. Once the face has been sealed and the tunnel reveal has been secured for the first time, the outer reinforcement mesh is installed and injected together with a steel support arch. If necessary, anchors are drilled to secure the rock in the tunnel. Finally, an inner reinforcement layer is installed and the shotcrete layer is completed to the required thickness. After filling the side track with excavated material, the cycle starts again from the beginning.