Engineers at Crossrail lowered a 550 tonne tunnelling machine into a 40 metre deep shaft in east London on 25th October.
The TBM, called Elizabeth, will be tunnelling under the River Lea towards Canary Wharf this winter. The team at Limmo Peninsula, adjacent to Canning Town station, will repeat the operation with sister machine, Victoria.
Work has started to prepare Crossrail’s Canary Wharf station to receive Elizabeth, with workers breaking out the hard concrete at the tunnel eyes to allow for the machines to enter the station next year.
Both tunnelling machines will receive maintenance while in the large station box, before continuing their journeys toward Whitechapel, Liverpool Street and Farringdon.
Says Andrew Wolstenholme, Crossrail’s Chief Executive, ‘This is a significant milestone for Crossrail’s progress in east London. Elizabeth and Victoria will construct Crossrail’s longest tunnel section – 8.3 kilometres between Canning Town and Farringdon. When Crossrail is completed it will dramatically improve transport in east London and bring places like Custom House and Abbey Wood to within 20 minutes of London’s major employment areas.’
The 1,350 tonne crane took weeks to assemble and includes heavy duty equipment to lower Elizabeth and Victoria into the enormous main shaft at the site. A smaller crane will lift the 10 gantries that form the back-up trailers of the tunnelling machine and carry the materials to support the tunnelling effort.
The assembly of the tunnelling machines and their gantries will be completed underground creating two 148 metre long tunnelling factories. After both machines and their gantries are safely in the shaft, a large conveyer system will be constructed to take the earth from the bottom of the shaft onto nearby ships.
The two machines will use large shove frames to push themselves forward into the earth. Works are also being completed on the River Lea to construct a jetty to berth ships that will take 1.2 million tonnes of earth to Wallasea Island to create a new RSPB nature reserve as well as a facility to dock barges that will bring 120,000 concrete segments from Chatham in Kent to line the tunnels.