The extension of the Metro B in Lyon achieves keys milestones
The Coline tunnel boring machine went into the ground once again on 3 April after 28 days of crossing the Oullins Centre station and is expected to emerge before the end of the second quarter of 2021 at the Orsel shaft. The departure of the station, as well as its arrival on 6 March, are decisive events for this major construction project carried out by the Implenia / Demathieu Bard consortium.
An emotional step for the team and the client
Since leaving the launch shaft in November 2019, Coline has covered two kilometers, laid 1100 precast segments and excavated more than 500,000 tons of material, 50,000 tons of which is recycled directly on site, saving more than 2,000 truck journeys (seven trucks full time). There are still 400 meters to go before it reaches its final destination, the "Orsel" shaft, the current terminus of the line.
Major construction work was necessary to enable this genuine factory train (120 meters long, 9.75 meters diameter of excavation, 1700 tons) to pass through the station.
This impressive underground factory employs around twenty operators organised into five teams who take turns working 24 hours a day, seven days a week. At the height of its activity, Coline digs at a rate of more than ten meters per day.
The diverse and complex geology of the region is one of the many challenges of this project. The multi-density tunnel boring machine was designed to cut through a wide range of different layers, using an engineered slurry developed specifically for this project.
Caption: A steel bell was installed against the cast wall to maintain the containment pressure of the TBM.
The metro station « Oullins Centre »
In the future "Oullins Centre" station, the different levels of the building are now completed and reveal impressive dimensions. The side panels of the central mezzanine have been completed, and the 13 meters high columns have been finished. The columns will remain in raw concrete and are already visible in their final form.
We congratulate the teams of the consortium for the quality of the intense work carried out.
