Gotthard base tunnel, Switzerland-sinking the Sedrum II shaft for the world's longest tunnel

摘要

The biggest challenge facing the engineers in the Sedrun tunnel section, which comprised two 6.2-km-long tunnel pipes, was having to work through very difficult geology and at the same time supply the drivages via the access drifts and two connecting shafts. The special plan to use a rodless shaft boring system for sinking Sedrun II shaft ultimately proved to be the correct one, given the steeply dipping schistosity of the Alpine strata that crossed the line of the shaft at an acute angle, and as a result the 800-m-deep shaft was sunk and lined within 12 months. By fitting out Sedrun II shaft to create a ventilation and winding shaft TRANSCO-Sedrun was able to obtain logistical advantages and contribute significantly towards tunnel safety, both during the construction stage as well as for the operating life of the permanent transport tunnel. The new winding installation, which was designed and installed by Thyssen Schachtbau GmbH, was commissioned in early February 2004 (Figure 11). Sedrun II shaft is an excellent example of how innovative mining technology is playing its part in modern tunnel construction.