Toulouse metro's breakthroughs

The Bessac CSM TBM being used to construct Lot 3 of the Toulouse Metro's 15km long, US$1bn Line B is scheduled to start boring next month. The 5.4m diameter backhoe will construct the 1,054m of tunnels in 5 short drives around Jean Jaures (including the station of the same name).

A JV, comprising Carillion, Urbaine de Travaux, Soletanche Bachy, Seso and Malet, is scheduled to complete the US$51M project over 45 months.

Tunnelling on Lots 2 (4.7km long), 4 (3.7km long) and 5 (3.2km long) started between August and October 2002 and is proceeding smoothly. Last month saw an FCB TBM breakthrough on Lot 4 into Empalot station (pictured). Lot 4 is being constructed by the Bouygues/Dalla Vera/Soletanche Bachy/Razel/ Demathieu & Bard/ Malet/Seso JV. This was preceded two weeks earlier by a Herrenknecht TBM breakthrough on Lot 2 into La Vache station by Campenon Bernard/Sogea Sud-Ouest JV.

The Vinci/Spie Batignolles JV is constructing Lot 5. A layer of water-bearing sand in the clay temporarily slowed Lots 2 and 5. Both sections are being constructed with EPBMs, and contractors had to inject polymers to help consolidate the face. The slurry machine on Lot 4, which also encountered the difficult ground, was able to maintain pressure at the face more easily.

Proving only a minor setback, Jean-Claude Jaubert, project manager with Systra, part of the project lead civil engineering consultant JV, told T&TI that the project is on target. The construction of the ventilation and pumping shafts are progressing smoothly, and the 2.5km of cut and cover at the north and south of the line (Lots 1 and 6) should be finished by the end of the year.

Lot 1 is being constructed by DV Construction/Sogea Sud-Ouest/Dodin/Botte Sade Foundation/Intrafor JV, while Lot 6 is being constructed by Chagnaud/ Condotte d'Acqua/Rabot Dutilleul/ DG Construction/Sopreca JV.

Line B is scheduled for operation in the summer of 2007.