Breakthrough was achieved last month on the 1.6km long second bore of the Pannerdensch Canal Railway Tunnel in Holland. The 9.8m diameter Herrenknecht Hydroshield TBM made good progress, placing up to nine rings a day in the clay, and up to 16 rings a day in the sand, at depths of up to 25m. Maximum advance rates of 36m/day were achieved.
The contractor, Comol Tunnelbouw (comprising Vinci/CFE/TBI), initially started the bore in August 2002, but stopped after about 40m to assemble gantries 3 and 4 as the launch chamber was not large enough to put together the entire machine. Boring then began in earnest in the last week of September 2002.
The US$200M tunnel was built with a pre-cast concrete segmental lining – seven and a key – leaving an i.d. of 8.6m.
The Herrenknecht was launched on the first bore in September 2001, and broke through on 3 June 2002. The machine was then dismantled and transported back across the canal by ship.
Cut and cover will make up the rest of the 2.7km long tunnel, which is one of six on the US$5bn Betuweroute east-west high speed freight rail line currently under construction in Holland. A bridge was ruled out in this instance, for fear of damaging this area of natural beauty.
The Pannerdensch Canal is in eastern Holland, halfway between Arnhem and Nijmegen.
Projectorganistatie Betuweroute is the client, with Arcadis and Maidl & Maidl acting as consultants. Dutch recruitment consultancy, IPS Personnel, provided a 70-strong workforce.
