Machine Type: Slurry
For the extension of the Thalys high speed rail link, via Antwerp, Rotterdam and Amsterdam, the Netherlands railway chose a route which crosses the “green heartland” of the Randstad. Environmental concerns in this rural region, north of Rotterdam, require the boring of a special tunnel nearly 15 meters in diameter, which would allow two trains travelling at more than 300 km/h to pass each other. This project set a world record for tunnel construction using a tunnelling machine. NFM Technologies, which was a Framatome subsidiary, built this tunnelling machine at its Le Creusot (Burgundy) plant.
Structure of the Project
The project has been carried out over a 65-month period and has a target date of operation of May 2005. It consists of a single tube tunnel 8,000 m in length, of which 7,160 m were bored by the tunnelling machine. Boring was carried out in sands and silts beneath a deep water-bearing stratum, under very high pressure compared with the surface aquifer (polder). Due to potential compression and subsidence risks, safety has been given the highest priority in the management of this project.