Crossrail’s first giant tunnel boring machine (TBM), Phyllis, has broken ground at Royal Oak to construct the first section of tunnel between Royal Oak and Farringdon.
Keith Sibley, Crossrail Area Director West said:
“Tunnelling for Crossrail has now commenced. Phyllis is now beginning to slowly disappear below ground and will steadily ramp up to the planned average tunnelling rate of around 100 metres a week.”
Following the official unveiling of 1,000 tonne Phyllis, Crossrail’s first tunnel boring machine (TBM) travelled 400 metres to Royal Oak Portal including under Hampden Street footbridge which was jacked up to allow the 7.1 metre diameter machine underneath.
The arrival of the TBM at the portal in mid-March allowed for remaining major works to get underway to support tunnelling.
A major piece of work has been the construction of the launch structure which allows the TBM to propel itself forward.
The total force required for the TBM to move forward is equivalent to the force needed to lift over 2,900 London taxis.
A steel seal has been fitted around the portal entrance to support the ground during the early stages of tunnelling.
Work has also been underway to install the major conveyor system behind the TBM to remove more than one million tonnes of excavated material from the cutter head to the portal entrance.
A total of 24 kilometres of conveyer belt will be used to construct the western tunnels, Crossrail said.
“The total force required for the TBM to move forward is equivalent to the force needed to lift over 2,900 London taxis.”
I was unaware that London taxis are used as a unit of force. I have heard about tennis courts or football fields as units of area and double decker buses as units of length.Â
This is a professional site so is there any chance of professional units that I may understand?
PS How long is Phyllis in DD Bus units?
Kit
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I am appalled at the mixture of units in your posting.  You must stick to one system of units, either using the MASS system (Measurement of Areas using Sports Similes) or the VIOLA system (Vehicles Instead Of Length and Area). It is not good to mix the two.
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And Phyllis is just under one and a half Lacrosse pitches long – I hope that clarifies matters.
Nigel