Following final breakthrough in late July 2018 of the western tube of Germany’s 9.5km long Filder Tunnel, crews from the ARGE ATCOST 21 JV are now disassembling and turning its 10.8m diameter Herrenknecht Multi-Mode TBM in a specially built underground cavern ready for a Fall 2018 launch on the remaining 3.4km of the eastern tube.
“Such an about-turn underground with a TBM of this size is absolutely exceptional,” says Dr.-Ing. E. H. Martin Herrenknecht. “This shows what extraordinary technical feats are being achieved during the construction work on the Filder Tunnel. Hats off to the site crew!”
The joint venture, consisting of Porr Bau GmbH Tunnelbau, G. Hinteregger & Söhne Baugesellschaft m.b.H., Östu-Stettin Hoch- und Tiefbau GmbH, and Swietelsky Baugesellschaft m.b.H. is constructing the tunnel through heterogeneous rock strata on a slope of up to 2.5 percent.
Due to the complex project requirements, initially no mechanised tunnelling was planned for the Filder Tunnel. However, the client, Deutsche Bahn was impressed enough by the flexible nature of the Multi-Mode machine to stipulate TBM tunnelling over a significant length of the tunnel.
In the upper section of the Filder Tunnel’’ western tube the convertible Multi-mode TBM worked in EPB mode with a screw conveyor for muck removal, whilst in the lower parts of the western tube it performed in open single-shield mode with belt conveyor discharge. The only area the machine was not used was in the geological transition zone, where miners removed the rock using diggers and blasting.
This final eastern tube drive, soon to begin, will see completion when the TBM once again reached this central transition zone.
The Filder Tunnel is the longest on the new line between Stuttgart and Ulm, which will link the new central railway station with the Filder Plain. As a result of the railway project, when operational in 2022, travel times between Stuttgart and Ulm will be almost halved. Around ten million passengers per year will benefit from the scheme.