Technical specifications

Scope of work

• 4 cooling water pipelines DN 3400
  with a length of 300 m each
• 1 fish return pipeline DN 1200
  with a length of 300 m
• start shaft: 30 m x 25 m x 15 m
  diaphragm walls with anchored underwater concrete slab
• target shaft: 45 m x 11 m x 15 m
  – steel girder shoring with underwater concrete slab and pre-installed lean concrete block
  – dyke crossing structure:
  5 circular cells of secant bored piles (internal diameter approx. 7 m)
  – a tunnel drive through each circular cell

Construction method 

• Pipe jacking using 2 slurry-supported tunnel boring machines
• external diameter: 4.1 m
• Jacking pipes: Composite pipes DN 3400
  consisting of a reinforced concrete pipe with an integrated HDPE pipe liner

Geology

• Silty sand with bands of clay