First, West Mont Sion Tunnel Breaks Through in FranceAfter eight months of tunnelling under the Mont Sion, Herrenknecht’s TBM dubbed ‘Adelaide’ has emerged to light on 12th June, 2007 at the south portal in Jussy, in the municipality of Andilly. The biggest TBM being used on the French territory, with its 12 metres of diameter, 180 metres of length and 2,200 tonnes of weight, tunnelled 3,100 metres of tunnel beneath the Mont Sion at an average speed of 30 metres a day, not taking into account the initial period of progressive work rate prior to cruise speed and the period for getting perfected the innovate Swiss method of placement of the precast segments. It also excavated some 340,000 cubic metres of rock and installed more than 9,000 concrete segments, weighing 16 tonnes each, which shape the inner lining of the tunnel.The wear and consumption of the cutting tools was limited because the ground was not abrasive. Herrenknecht is also the supplier of the cutting tools. During tunnelling of the first tunnel, crews successfully met the challenge of crossing 12 faults, with production of blocks and convergence of the ground on the machine. The foreseen date for the start of the second bore is September 2007 after disassembly, transport and reassembly of the TBM. Click here and fr/56. Visit www.adelac-a41.com and www.herrenknecht.com 25/07.