Andre tunnel med TBM

The San Gottardo Second Tunnel North project (Lot 241) includes the construction of a second tunnel tube, a fault zone drive north, the second stage of a precut, a TBM launch section, cross connections, ventilation control centers, and exhibition bays. The primary tunneling will be performed using a tunnel boring machine (TBM) with single shield and segment lining up to the north fault zone, followed by machine-assisted full excavation from an access tunnel within the fault zone.

Hovedarbeider og TBM-utgraving

The main works involve excavating a precut with a volume of 24,000m³, a main tunnel section with a length of 86 m and area of 180m², underground concrete center construction, and various blasting operations for logistics structures and the fault zone. The TBM excavation will cover a length of 6930 m with a diameter of 12.26 m. Additionally, the project includes constructing underground concrete centers, ventilation stations, cross connections, and other subsurface facilities.

Utfordringer med forkastningssone

One of the project's major challenges involves special heading through a fault zone, which requires flexible supports and multiple blasting operations for logistics and main tunnel display bays. Advanced geology management is crucial as the tunnel will traverse diverse rock formations ranging from granite and gneiss to calcareous and clay schists. The project sustains its efforts with a comprehensive use of excavated materials for construction and environmental restoration, including renaturation of Lake Uri and terrain modeling in Airolo.

Prosjektledelse og tidslinje

The project, led by the Swiss Federal Roads Office (ASTRA) and managed by IG Nouvo Gottardo, is set to significantly enhance the infrastructure linking northern and southern Switzerland. The construction phase commenced in October 2022, with a projected completion by October 2029. The significant investment in infrastructure underscores the project's importance, with a contract sum of 433.434 million CHF.