Repair of Pressure Tunnel B

Pressure Tunnel B, which was built in the 1920s, is to be repaired in two phases. Due to space constraints a linear construction site is necessary. Construction work will last approx. 2.5 years.

Area requiring total repair (l=1,250 m):

  • The existing lining will be largely removed and replaced with shotcrete.

Selective repair (l= 6,250 m):

  • Damage in the remaining tunnel area will be selectively repaired using concrete patches and polyurethane injections.

Main Data

  • Reprofiling mortar (selective repair): 280 t
  • Shotcrete (total repair): 3,200 m3
  • Polyurethane injections (selective repair): 80,000 l


KW Amsteg AG


IUB Engineering AG

Construction period


Construction costs

Approx. CHF 10 million

Scope of services

  • Planning and general management
  • Design for construction
  • Design for regulatory approval
  • Tendering
  • Implementation project
  • Execution