Dual mode TBM wraps up mountain drive 12 Mar 2013
Herrenknecht News Release
- Excavation is complete for the Vosges mountain crossing section of the latest extension to the French TGV high speed rail link system.
Celebrating final breakthrough in France
- An innovative dual mode Herrenknecht 10.01m diameter machine, operating on behalf of the French construction consortium Spie Batignolles TPCI/ Dodin Campenon Bernard, has achieved final breakthrough on the 3.85km-long Tunnel de Saverne south tube following a drive that began in late September last year (2012).
- During the tunnelling of the second tube, the site teams achieved a record performance of 1,014m in 30 days and a best daily performance of up to 46m. Overall, for both drives, the TBM completed a distance of nearly 8km in hard and unconsolidated rock.
- The Herrenknecht TBM, featuring a convertible EPB shield, was specially adapted to handle two different soil types. It worked through the first 200m of unconsolidated rock on the south tube in the closed EPB mode before adjustments made at the cutterhead enabled excavation through the prevailing hard rock red sandstone that followed in open mode.
10.01m dual mode TBM equipped for two soil types
- The conveyor belt and screw conveyor were able to remain in place on the machine in both modes, making this the first time a Herrenknecht TBM with a convertible EPB shield has been able to handle open hard rock mode with the same belt conveyor.
- Final breakthrough on the south tube occurred on February 25 (2013), in two months less time than the parallel north drive and well ahead of schedule.
- The twin-tube rail tunnel is part of the section on the TGV Paris-Strasbourg line currently being expanded for speeds of up to 320km/hr. The French TGV currently takes two hours and 20 minutes from Paris to Strasbourg. Further expansion eastwards over 106km through Alsace to Strasbourg is running at full speed in order to shorten the journey time for passengers by 30 minutes from 2016.
Innovative TBM powers through mountains - TunnelTalk, September 2012
Add your comment
- Thank you for taking the time to share your thoughts and comments. You share in the wider tunnelling community, so please keep your comments smart and civil. Don't attack other readers personally, and keep your language professional.