Skip navigation

Dietershantunnel

The 7,345 m long Dietershan Tunnel is located at the northern periphery of the city of Fulda. In the north it passes through the variegated sandstone formations of the Gerzberg between Fulda and Haunetal at depths ranging from 15 to 85 m and in the process, twice undercuts the A 7 federal motorway. The tunnel was built with two shells using the NATM with blasting from both tunnel portals. Supporting was mainly accomplished with wet shotcrete 10-25 cm thick and 1-2 layers of structural steel meshing and SN anchors. The reinforced inner shell was created with 40 cm thick, watertight WU concrete. The tunnel was only provided with a sealing membrane at points where highly aggressive underground water was present. The placing time of the shotcrete could be reduced from around 150 to 40 min, through the selected wet-spraying method given a block length of 2 m. Work on the Dietershan Tunnel commenced in May 1983. The crown drive was completed following 28 months of tunnelling in December 1985. The carcass work was over in April1987. Driving was staggered divided up into crown and bench as well as excavation and installation of the base. The crown drive with an excavated cross-section of some 60 m² was some 100 to 150 m in advance of the bench drive and governed the rate of advance. Up until a driven length of 1,800 m, ventilation came from the portals. At that point, the so-called "radio bores" were encountered, which created a link-up to the ground surface for the radio equipment for subsequent train services. These "radio bores" were made with a greater diameter and as a result, they could be used for ventilation purposes and later as compressed air relief ports when trains started passing through the tunnel. The formwork car that was used was extensible which meant that all the vaults could be built with the various effective cross-sections.

 

  • Country: Germany
  • Region: Hessen
  • Tunnel utilization: Traffic
  • Type of utilization: Main-line rail
  • Client: Deutsche Bahn AG
  • Main construction method: Trenchless
  • Type of excavation: Drill-and-blast
  • Lining: Concrete formwork (WP concrete)
  • No. of tubes: 1
  • Tunnel total length: 7345 m
  • Cross-section: 120-150 m²
  • Contract Volume: 165 mill. DM
  • Construction start/end: 1983-1987 (48 months)
  • Opening: 1987