Our expert, Michael Proprenter talks about "17 miles of SEM and TBM tunneling under challenging conditions in Austria".
"The Semmering Base Tunnel is a major infrastructure project in Austria, Europe. This consists of two 17 miles of single-track railway tunnels, numerous cross passages and a complex underground emergency station including caverns, passages, tunnels and two 1,315 ft. deep ventilation shafts. Intermediate access for construction is provided by a 1.1 mile long, temporary tunnel with two 820 ft. deep subsurface shafts at its end and two additional temporary shafts from the surface with large underground caverns at the shaft bases. The maximum overburden is around 2,850 ft. in difficult, frequently changing geological conditions with large fault zones and extensive water inflow of up to 300 l/s requiring special grouting and support measures. The underground construction works using SEM as well as TBM methods commenced in 2014 and will be completed in 2026."