Contractors working for HS2 have transported a 160t tunnel boring machine cutterhead to a new digging site in a complex overnight operation.
Tunnel boring machine Dorothy has already made its first tunnel breakthrough in July this year in HS2’s Chiltern Tunnel at the south portal.
Now Balfour Beatty Vinci (BBV) has moved the TBM’s cutterhead back to the north portal.
The cutterhead sat upright on a 12m-long, 48-wheel self-propelled trailer as it made its journey along the A425, through the village of Ufton, to the north portal. The 2.5-mile-long journey took three hours, arriving at 2am.
BBV has already used specialist equipment to transport eight other large pieces from the TBM’s front shield, middle shield, and tail-skin.
The rest of the 120m-long TBM will be pulled back through the mile-long tunnel by a ‘caterpillar’ system at the pace of 150m a day.
Once all the parts are back at the north portal, BBV will reassemble the TBM before starting the second bore later this year.
