TBM Caroline completes 5 mile journey - TBM miner inspecting final tunnel rings being installed

HS2's TBM Caroline, is the second machine to reach the Green Park Way vent shaft in Ealing. The 2,050-tonne TBM broke through into an underground reception can filled with foam concrete, and installed the 4,217th concrete tunnel ring to complete the 5-mile stretch of tunnel. In image - TBM miner checking the tunnel ring segment installation