by Helen Young January 3rd, 2012
Preparations for the start of the biggest civil engineering project in Europe are well under way as the first of eight enormous digging machines makes its way to London. The Tunnel Boring Machines will be used to excavate 21kms of tunnel beneath the capital for the Crossrail scheme. The digging part of the process is expected to last for two years, after which engineers will lay 118kms of railway track.
Each TBM is the equivalent of a football pitch in length and weighs around 1,000 tonnes. They are being made by Herrenknecht in Schwanau in Germany and the testing part of the process is now over. Each has to be taken apart for shipping and the first will be put back together in London’s Royal Oak which is the site of the tunnel entrance.
Each £10 million giant is able to dig its was through around 100m of clay each week. The earth will then be taken to Essex where it will be used to build a new nature park. The Crossrail project will cost £14.8 billion to complete and will employ 10,000 workers.
The operation of each TBM will be the responsibility of gangs of 20 people who will work in shifts as the machines are expected to operate around the clock. A new academy has been established especially to train those who will be working in the subterranean environment.
A factory has also been established which will be used to create the 3.5 tonne concrete structures used to line the tunnel.