TUNNEL OF MOUTIER, SWITZERLAND: CHANGE FROM A TBM TO THE GERMAN EXCAVATION METHOD

摘要

Located in the Jura Mountains in Switzerland, the tunnel of Moutier is a 1.2 km twinrntube highway tunnel. The excavation started with a shielded 11.70 m diameter TBM,rnbut the TBM became stuck in a geologically disrupted zone after 190 m-resulting inrnextraordinary consequences to the project. In order to free it, the top heading of thernTBM tube had to be completely excavated with conventional excavation methods asrnwell as a roadheader; the worst 100 m were executed using the German excavationrnmethod: a Sequential Excavation Method (SEM), where the TBM was pushed throughrnat a later time. The other tube was excavated using conventional methods as wellrnas a roadheader. This paper shows the reasons that led from a TBM to a SequentialrnExcavation Method (SEM).