Challenges

• Very limited space in the tunnel
  (cross-section 1.85 m)
• Narrow tunnel width combined with high material requirements
• Difficult conditions for transporting material to the processing site
• 3,000 m of track-bound tunnel from the construction site access area to the work site
• Limited infrastructure due to the remote location of the construction site in the Gruyère Nature Park

Approach

• Space-saving custom design of multiple pressure vessels with minimal footprint. This custom design enabled the building material to be transported in the pressure vessels on rails through the tunnel to the processing site.
• Large quantities of building material were flexibly available via our storage silos, ensuring uninterrupted construction progress despite limited access routes.
• Use of steel fiber-reinforced (reinforced) dry shotcrete

Products Supplied

• Sulfate-resistant dry shotcrete C 35/45 with steel fibers, sulfate-resistant, accelerated J2, grain size 0–8 mm

Techniques supplied

• Four pressure vessels, each 3,2 m³, custom-made
• Two storage silos, each 29 m³
• One storage silo, 22 m³