Le tunnel du Raimeux Conception et execution - Passage de la molasse

摘要

The Mont Raimeux tunnel is 3,200 metres long, and comprises a twin-track two-way tube with a parallel safety gallery over its entire length. It includes a cavern exhaust ventilation unit, and a foul air removal shaft 250 metres high and 5 metres in diameter. The subsequent construction of a second tube is allowed for by the project. Excavation is performed partly by explosive or by mechanised facilities in rocky ground formed of multiple alternations of the karstified limestones and swelling marls of the Middle and Upper Jurassic. The article deals in special detail with the passage through the Alsatian molasse of very mediocre quality, which required detailed scheduling and very close control of excavation work.