Excavation was completed in March for the first westbound tunnel of the new Piccadilly Line extension at Heathrow Airport Terminal 5 in the UK.
The 1.6km long tunnel was completed 10 days ahead of schedule on 16 March. Tunnelling gangs consistently achieved advance rates of 50 rings per day for the 4.5m diameter tunnel.
The Morgan/Vinci joint venture used a 4.8m diameter open face Dosco TBM to construct the new tunnel with less than 4m clearance to the existing Piccadilly Line above. Real time monitoring was carried out throughout the tunnelling activities and service on the Piccadilly Line to the other four terminals was not affected.
Ian Fugeman, T5 head of rail and tunnels, said: “This was an excellent demonstration of teamwork and a good working relationship with London Underground and Tube Lines.” The second tunnel drive is due to commence in April.
