Tunnel Boring Reaches Key Milestone at Toulouse’s Matabiau Metro Station
Toulouse, France – A tunnel boring machine (TBM) has successfully pierced the Matabiau metro station wall, marking โa notable advance in the construction of Toulouse’s Line C extension. โTheโค operation, completedโ using โa specialized “bell drill” technique, avoids disruption toโข nearby โinfrastructure including Line A,โ the Marengo station, and SNCF rail works.
The Matabiau station construction employs a unique method to minimize impact on surrounding structures. Unlike previous stations where drilling wasโค visible, here the TBM entered the station within a 10-meter diameter, 15-meter long metallicโ airlock – a “bell” – to excavate and install the tunnel’s final structure while maintaining the station’s waterproofingโ andโ stability. Prior toโข the TBM’s arrival, the bell was filled wiht soil to maintain pressureโ until the โคfinal tunnel ring was laid, connecting the tunnel to the station โwalls.
According to Tissรฉo, the techniqueโฃ is dictated by local geological conditions, including soil characteristics and groundwater โpresence. It has previously been used atโค the Colomiers Gare and Bonnefoy stations.
The TBM, named Marie-Thรฉrรจse deโค Villeneuve Arifat, has now โtraveled 1.2 km, completing 30% of its 4 km route. 42%โ of โคthe Line C extension’s layout has been excavated. The next โphase will take the TBM towards theโ Franรงois-Schovie station, another โsensitive area where it will intersect with Lineโข B.