Herrengosserstedt
Finne Tunnel
Herrengosserstedt, Germany / 12.2006 - 12.2012
The Finne Tunnel forms part of the new Erfurt–Leipzig/Halle line within the VDE 8 project. The joint venture comprising PORR Tunnelbau GmbH and PORR GmbH & Co. KGaA carried out the tunnelling work for DB Netz AG. With a length of 6.83 km, the Finne Tunnel is one of the key tunnel structures on the line.
Facts & Figures
Company
PORR Tunnelbau GmbH and PORR GmbH & Co. KGaA in a consortium
Type
Tunneling
Runtime
12.2006 - 12.2012
Twin-tube railway tunnel for the new Erfurt–Leipzig/Halle line
Twin-tube tunnel for high-speed rail
The Finne Tunnel consists of two parallel, single-track tunnel tubes with a total length of 6,822 m. Construction work was carried out in stages between 2006 and 2012. Since the end of 2012, the tunnel has formed part of the new railway line and is designed for speeds of up to 300 km/h.
Shield tunnelling with reinforced concrete segments
Both tunnel tubes were constructed using shield tunnelling. In some sections, tunnelling was carried out using a fluid-supported working face. The tunnel structures were constructed using a single-shell lining of reinforced concrete segments. The segment rings have an external diameter of 10.82 m. In total, approximately 1,547 m of each tunnel tube was excavated using a fluid-supported working face under water pressure conditions of up to 6 bar.
Start and finish excavation pits
Extensive start and finish excavation pits were constructed for the tunnelling works. These were used for the installation and recovery of the tunnelling equipment, as well as for the connection to the subsequent tunnel structures.
Groundwater control over 4.45 km
Groundwater lowering was implemented to safeguard the construction works. A total of 178 boreholes were used for this purpose along a stretch of approximately 4.45 km. These measures were carried out concurrently with the construction of the tunnel tubes.
Cross-passages and ground freezing
Sixteen cross-passages were constructed between the two tunnel tubes. Two of these cross-passages were created using a ground freezing method. The cross-passages serve to connect the two tunnel tubes and form part of the tunnel infrastructure.
Tunnel portals and open-cut construction
The scope of works also included the tunnel portals, sections constructed using the open-cut method, as well as associated earthworks. In addition, terrain modelling and further infrastructural adjustments were carried out in the vicinity of the tunnel.
Part of the new Erfurt–Leipzig/Halle line
The construction of the Finne Tunnel marked the completion of a section of the new Erfurt–Leipzig/Halle line. The structure forms part of the railway infrastructure of German Unity Transport Project No. 8 and connects the line sections in the Herrengosserstedt area.
