Technical specifications

Project description

• 95 m preliminary cut, preliminary cut approx. 35,000 m³
•  30 m north portal structure

462m tunnel constructed by the mining method:

• Top heading and bench/invert heading in Tertiary hilly terrain
• Spile canopy support system approx. 300 m
• “Dry” tunnelling due to a substantial lowering of the groundwater table
• Tunnel route runs partly through built-up areas

12 m shaft construction:

• 2 tunnel blocks in open cut construction
• Bored pile excavation (pile lengths up zo approx. 30 m)
• Bracing at 4 levels and 2 excavation levels (tunnel / service building)
• 179 m top-down method using bored piles

Deviations in geology identified subsequently:

• Impacts: Bored pile design / bracing / foundation of stream crossings /
• subsoil improvement in the Moosach area / additional time required / crossing of Moosach stream and construction of a diversion channel
• 192 m open cut construction method with south portal structure and trough structure (ramp): Unstable soil (peat), consolidation fill requiring
• a waiting time over 6 months
• Underwater excavation partly in peat
• Underwater concrete base anchored with Gewi piles
• Inner diameter: approx. 10.4 m
• Max. cover: approx. 10 m

Excavation cross-section: approx. 100 m²

• Length = 328 m, A = 13.5 – 18.3 m²

Construction method
Conventional excavation after substantial lowering of the groundwater table, civil engineering structure constructed by the top-down method using boring piles, open-cut method and trough in bored pile excavations

Geology
Tunnelling using mining techniques in Tertiary hilly terrain north of Munich, top-down method and open cut construction in the transition area mainly in Quartenary soils, foundation lying on Tertiary soil