The construction of tunnels using conventional construction methods has always been a challenge to every engineer. Here, the engineer’s most important task is the evaluation of the geology and the selection of the right means of securing the excavation face until final completion of the inner lining. Wayss & Freytag already rose to this challenge in 1905 when building a railway tunnel using the conventional tunnelling method in Wasserburg/Inn in gompholite (Nagelfluh) and gravel.
The range of conventional tunnelling reaches from soft rock tunnelling (e. g. a metro tunnel in Munich gravel) and tunnelling in compressed air (e. g. Ostbahnhof metro station in Munich in Tertiary formations below groundwater) to classic drill and blast drives (e. g. Rennsteig Tunnel on the A 71 motorway, which, with a length of 8 km, is the longest motorway tunnel in Germany).
1 two-lane road tunnel and 1 bridge, total tunnel length 100 m, length of the total section to be built by us under the contract: approx. 520 m
The new hydroelectric power plant supplies sustainably produced electricity for approx.100,000 households without emitting pollutants in Tyrol and Engadin. Power house and power descent were built by Wayss & Freytag Ingenieurbau.
Due to an advantageous layout of tunnel portal and tunnel excavator is was possible to do without shunting bays and laborious shunting during the construction of the single-track railway tunnel.
The Henndorf bypass lead to a noticeable relief of traffic congestion. Centrepiece of the bypass is the double lane 2,150 meters long road tunnel, which is now used by approx. 20,000 vehicles per day.