Technical specifications

Scope of work:

  • Start shaft diameter: Ø 15 m, depth: 22 m
  • 600 m single-track cross-section excavated area = 36 m²
  • 200 m double-track cross-section excavated area = 70 m²
  • 70 m enlargement section excavated area = 36 m² - 60 m²
  • 30 m branch-off section, three-bay excavated area = 185 m²
  • 100 m station tubes excavated area = 62 m²
  • 80 m station section, three-bay excavated area = 138 m²

Construction method:

  • Sprayed concrete lining (SCL) method with tunnel excavator, partly with pipe umbrella support system
  • cut and cover method:
    western and eastern railhead of the stations with accesses
    100 m closed ramp as a double-track rectangular cross-section
    120 m open ramp as a retained cut


  • Marl stone
  • weathering zone of sandy, gravelly and silty clays

General data

Dortmund Ostentor Light Railway Line III
Contract Section S10.1, 2nd Stage

Stadt Dortmund, Stadtbahnbauamt
[City of Dortmund, Light Rail Construction Authority]

Wayss & Freytag Ingenieurbau AG
as technical leader of a joint venture

Construction period
March 2002 to December 2005

Construction costs
€ 40 million

Metro tunnel
1,230 m
Construction Method
SCL method with tunnel excavator, cut and cover method
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