Contractor JV, Comol Tunnelbouw was scheduled to start boring the second 1.6km long tube of Holland’s US$200M Pannerdensche Canal Railway Tunnel as T&TI went to press. Construction of the first tunnel was completed successfully following the TBM breakthrough in June this year.
The JV, comprising Vinci/CFE/TBI, is using a 9.8m diameter Herrenknecht Hydroshield, to bore the tunnels through the mainly sandy geology at depths of up to 25m. The slurry shield machine is erecting a pre-cast concrete lining consisting of seven segments and a key bringing the i.d. down to 8.6m.
The first bore started from the 50m long, 30m wide and 20m deep launch chamber in September 2001. Rates of 10m per day were achieved on the machine’s way to the reception chamber 1.6km away. The reception area forms a special feature of the project as it is a refilled former sandpit. The 200m x 200m x 20m area was refilled with 500,000m3 of vibroflotation compacted sand to support the lining and prevent blowout as the machine entered it.
Upon reaching the chamber the machine was dismantled and transported back across the canal by ship, reassembled at the start chamber ready for the imminent launch on the second tube.
Construction of the twin tunnel is due to be complete by the middle of next year. The Pannerdensche Canal Tunnel is one of six tunnels on Holland’s US$5bn Betuweroute high speed rail link. The 160km long double track line will form a dedicated freight railway linking the port of Rotterdam to the European hinterland.
The client for the project is Projectorganisatie Betuweroute with Arcadis and Maidl & Maidl acting as consultants. The complete line is scheduled to open in 2006.
