Steinbühl and Bossler Tunnels

Project Description

The 8.8 km long Bossler Tunnel and the 4.8 km long Steinbühl Tunnel are part of the new railway line between Wendlingen and Ulm, consisting of two single-track tubes with cross passages. The Bossler Tunnel was originally planned with a 2 × 2.6 km TBM drive, while the remaining section was to be constructed using shotcrete construction. The construction sequence enabled early geotechnical insights through cyclic excavation as well as an investigation shaft and gallery before the TBM drive commenced, confirming its feasibility in the core section. Due to high rock pressure and karst potential, the TBM drive was extended following the principles of the observational method, accompanied by a comprehensive
investigation and monitoring programme. The Steinbühl Tunnel is entirely constructed using the shotcrete construction method. Pressurised rock conditions and karst potential made it necessary to extend the TVM drive using the observation method with a comprehensive exploration and measurement programme.

Project data

• Bossler tunnel: l = 8,806 m
• Steinbühl tunnel: l = 4,847m
• Two single-track tubes each with connecting structures
• Tunnel diameter: approximately 10 m, TBM diameter: 11 m

Services

iC was responsible for the preliminary design of the TBM-driven tunnel for the consortium ATA and the final design of both the tunnels.