The challenges of contract SBT1.1 "Tunnel Gloggnitz" / Die Herausforderungen des Bauloses SBT1.1 Tunnel Gloggnitz

The second of the three tunnelling contract sections of the Semmering Base Tunnel is of comparable complexity to the first contract section SBT2.1. The geotechnical and hydrological conditions for sequential tunnelling are demanding and require extensive grouting and investigation measures in advance of the drives. The enormous extent of the construction works and the need to access parts of the running tunnels through an intermediate construction access are a logistical challenge. The construction time is also very ambitious. These circumstances had to be considered in the production of the tender documents.