Published: 12th September 2013
Europe’s largest construction project is approaching the half-way stage in tunnelling terms. The project, Crossrail, is the £16 billion railway scheme being built under London and in five years’ time will enable up to 24 trains an hour to run in each direction between Paddington and Liverpool Street.
The project will provide another 10% rail capacity and overcrowding should reduce considerably and commuting become somewhat easier. Through trains from Maidenhead and Heathrow will serve the City with Liverpool Street becoming a major interchange on the new route. For example, it will take about 33 minutes Liverpool Street and Heathrow Airport and just seven minutes to Canary Wharf.
But until the route opens, it has to be built, or rather bored through London without disturbing London’s surface structures and population. A major point has been reached with a Tunnel Boring Machine (TBM) named Mary breaking through into the Woolwich station box, which means that half way has been reached in the tunnelling works south of the river.
TBM Mary has been boring since May now joins TBM Sophia to continue boring under The Thames to North Woolwich. Once complete, the tunnel will create a rail route between Plumstead and North Woolwich making travel easier than now. TBM Mary has been busy this summer and has excavated 110,000 tonnes of material from beneath London.
Gus Scott, project manager for Crossrail’s Thames Tunnel, said: “It’s great to know that we’re half way through our tunnelling in southeast London. Mary and Sophia have done a fantastic job so far, between them constructing a mile and a half of brand new tunnels from Plumstead to Woolwich.”
TBM Mary is no slim lady weighing in at a thousand tons and with sister TBM has removed 200,000 tons of material. As well as TBM Mary’s boring work, she has also installed 811 concrete rings which form the tunnel wall lining.
The Crossrail project will provide a significant regeneration boost in the Woolwich and Abbey Wood areas by making travel easier and quicker as well as during in the construction phase supporting jobs and local businesses. When trains commence, the journey from Abbey Wood and Woolwich to Bond Street will save at least 15 minutes and Heathrow passengers will save 40 minutes travelling times.
“It’s great to know that we’re half way through our tunnelling in southeast London. Mary and Sophia have done a fantastic job so far, between them constructing a mile and a half of brand new tunnels from Plumstead to Woolwich.”
While TBM’s Sophia and Mary construct the Thames tunnel between Plumstead, Woolwich and beneath the Thames to North Woolwich, different TBMs used purely for tunnelling are also being used on the Crossrail project. These are known as ‘slurry’ machines and designed to deal with the chalk, flint and wet ground conditions found in southeast London.
The material excavated is pumped out as slurry to Plumstead where there is a special site which separates it into sand, gravel, water and chalk which emerges from the process as slabs of filtered chalk particles.
Named after Olympic athletes, TBMs Jessica has just set out to be followed by Ellie in a few months on a 1.7 mile marathon dig for Crossrail. The name for Crossrail’s seventh and final eighth TBMs was suggested by the Marion Richardson Primary School in Stepney.
Jessica’s boring task commenced at Stratford and will create a 1.7 mile Crossrail tunnel from Pudding Mill Lane, near the Olympic Park, to Stepney Green. Sister TBM, Ellie, named after Paralympic gold medallist Ellie Simmonds OBE, will build a second tunnel.
The other six TBMs burrowing away under London are virtually at the half way stage so far as boring out the 22 miles of tunnels is concerned. These tunnels will connect on an east- west basis London and 37 stations between Maidenhead and Heathrow in the west, to Shenfield and Abbey Wood in the east.
Transport Minister Stephen Hammond said: "The Government is investing record amounts in the country’s infrastructure because we recognise its importance in driving the economy forward and pushing the UK ahead in the global race. The launch of the last pair of tunnel boring machines in the shadow of the Olympic Stadium marks another significant milestone in the Crossrail project, as we approach the halfway stage in our tunnelling marathon."
"Crossrail is making good progress with more than 11 miles of tunnel now built. We're delighted that our final two tunnelling machines, which start their race at Stratford, have been named after two Olympic heroines and will deliver their own tunnelling marathon under London.
Crossrail say that naming TBMs after women continues a long-held tunnelling tradition. The first six Crossrail TBMs were each inspired by British heritage and history. Tunnelling machines Ada and Phyllis were named after early computer scientist Ada Lovelace and Phyllis Pearsall who created the London A-Z and they are creating the tunnel linking Royal Oak near Paddington and Farringdon.
Elizabeth and Victoria, were named after Queen Victoria and Queen Elizabeth II and building the Canning Town to Farringdon tunnel. Mary and Sophia were named after the wives of famous railway engineers Isambard Kingdom Brunel and Marc Isambard Brunel and working under the Thames.
More than 8,000 people are currently working directly on Crossrail, which is Europe’s largest construction project, with another 5,000 full time equivalent jobs in its supply chain.
Crossrail has introduced a fun aspect to their project. They have created a ‘Near You’ mapping tool to enable anyone to find out which TBM lady is where at any given moment. The Crossrail route is shown and by using the search tools to zoom to a location to see current construction works, then click on the tunnel boring machine cutterhead symbol for information about tunnelling progress.
Who ever said Crossrail was a boring project!