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Upgraded/new Karlsruhe-Basle Line, Katzenberg Tunnel New Schlüchtern Tunnel, in PFA 8.1

Between Karlsruhe and Basle the Rheintalbahn (Rhine Valley Line) is being expanded from a two-track to a continuous four-track system. The Katzenberg Tunnel with a new route alignment compared with the original one is the largest single construction scheme on this line and Germany's longest tunnelling machine (TBM) project concerning 2 single-t rack tubes with a monocoque lining. The 60 cm thick reinforced concrete segments, altogether 63,000 of them, were produced on a field factory within the site area. In 2003 the Katzenberg Tunnel JV was awarded the contract after protracted negotiations following bids which were received from throughout the EU. The tunnel passes through various geological formations. ln addition to quaternary covering layers in the marginal zones investigation of the subsoil revealed the presence of mainly tertiary sedimentary rocks such as claystone, silt stone and occasionally sandstone with different stages of weathering. Starting from the south the drives penetrated quaternary, coloured marl and Eocene formations. In addition Jura mass limestone was encountered in a rough\y 800 m long section in the south. In the peripheral areas of limestone as well as in areas with very shallow tertiary overburden above the tunnel occasional water incursions were mastered. Furthermore continuous water influxes during the drive in areas containing fish shales and Meletta layers resulted in considerable outlay in terms of removing the material from the machine and the tunnel, with regard to preparing the material in the intermediate storage site BE Süd and in the final storage site, the Kapf quarry, connected by conveyor belt some 2.5 km away. The 2.45 mill. m³ of tunnel muck was dumped in an up to 60 m high earthen structure. After commencing the excavation in June 2005 with two TBMs with EPB shield from the south portal at Efringen-Kirchen the breakthrough at the north portal near Bad Bellingen took place at the start of October 2007 after 28 months and 8,986 m of driving given overburdens between 20 and 110 m as well as a dimensioning water pressure of 9 bar for the segmental lining. The 18 cross-passages set between the tunnel tubes at 500 m gaps were produced by excavator and shotcrete supporting, plastic membrane sealing and in situ concrete inner shell. After removal of the two TBMs the portals were produced in reinforced concrete with so-called sonic boom structures in temporary excavation pits: since spring 2007 in the north (286 m long single cell and twin cell frame structures) and since autumn 2008 in the south (a 115 m long triple cell frame structure). ln addition since April 2008 within the scope of the contract the in situ concrete cable ductwork has been produced on the left and right sides next to the ballast-free superstructure (slab track system), which is to be built in at a later stage as a separate contract section.


  • Country: Germany
  • Region: Baden-Württemberg
  • Tunnel utilization: Traffic
  • Type of utilization: Railway Tunnel with ICE Traffic
  • Client: Deutsche Bahn AG/DB Netz AG represented by DB Projektbau GmbH, NL Südwest Karlsruhe
  • Tunneiling Technical Consultant: Prof. Dr.-Ing. Dieter Kirschke
  • Consulting Engineer: Lahmeyer/PSP (design), PG Ed. Züblin AG/Wayss & Freytag Ing.-Bau AG (execution)
  • Test engineer: WBI, Aachen/Krebs und Kiefer, Karlsruhe
  • Construction monitoring: Bung AG/gdm/der
  • Contractor: Ed. Züblin AG, Wayss & Freytag Ingenieurbau AG, Marti Tunnelbau AG, Jäger Bau GmbH
  • Main construction method: Trenchless
  • Type of excavation: Shield machine(SM)
  • Lining: Reinforced concrete segments
  • No. of tubes: 2
  • Tunnel total length: 2 x 9,385 m including 2 x 8,984 m (TBM drive by mining means), 115 and 286 m (cut-and-cover)
  • Cross-section: 98 m²
  • Bored diameter: 11.16 m
  • Contract Volume: approx. 290 mill. Euro
  • Construction start/end: September 2003 till approx. December 2010
  • Opening: December 2012 (scheduled)