Extension of Line 14: the first section now completed
1594m of tunnel have been excavated between Pont-Cardinet and Saint-Lazare in the space of 6 months. SYSTRA’s teams are now getting ready for the return of the tunnel-boring machine (TBM) to its starting point, and its redeployment, in the summer, to reach Saint-Ouen.
Launched in November 2015 from the shaft of the future Pont-Cardinet Station, the Magaly TBM has achieved the excavation of the first section of the Line 14 extension. The TBM has just reached the end of the tunnel of the current Line, underneath the Gare Saint-Lazare railway station, in only 6 months. To date, there have been no problems to deal with, and settlements and deformations have, in fact, been lower than the values projected in studies by SYSTRA, while context is delicate (sensible Parisian basement, crossing under the metro Line 2 and 13….). 1594 metres of the tunnel have been excavated, at an average speed of 15.5 metres per day, and a depth of almost 20 metres. Close to 6,200 concrete lining-segments have been laid in the tunnel, which has an external diameter of nine metres.
Some 96 metres long and weighing 1,400 tonnes, the Magaly TBM is now being dismantled inside the tunnel it has just excavated. Its work is not yet complete: it will be reassembled again at Pont-Cardinet, this time to bore northwards, passing through the Porte de Clichy metro station, and on, to the future Clichy-Saint-Ouen station, in 2017. However, to meet the project timescales, a new shield has already been assembled, and is ready and waiting for the following train. Once in position, the new TBM will be re-launched. This project, being delivered under a mission of joint project ownership of RATP and STIF by the Eiffage TP/ Razel/ Bec consortium and SYSTRA’s teams, operating from their base-site at Pont-Cardinet, will be moving forward apace, to meet the extension’s opening date, scheduled for mid-2019.
Picture: entrance of the tunnel in Pont-Cardinet.