Major project – “Gotthard”
St. Gotthard railway tunnel, Switzerland

New construction of the St. Gotthard railway tunnel: 57 kilometers in length, the longest railway tunnel in the world.

Around 130.000 m² dimpled sheet type ISO-DRAIN eco 20 in use!

ISO-DRAIN dimpled sheet as a soil layer

ISO-DRAIN eco 20 is ideally suited for tunnel construction, cause there is a high burden in case of cleft- and groundwater. As a partition between shotcrete and tunnel ISO-DRAIN eco 20 offers positive characteristics.

Overview of advantages:
  • high drainage efficiency
  • safe diversion of the water into the existing drainages and seepage layer
  • extremely resistant
  • usable as „lost formwork“