HS2 has begun assembling the project’s longest ‘green tunnel’ – designed to blend the high-speed railway into the rural landscape and reduce disruption for communities around Greatworth in West Northamptonshire, United Kingdom.
Unlike a bored tunnel, the shallow one-and-a-half mile (2.7km) tunnel is being built using a ‘cut and cover’ process. This involves excavating a cutting, building the tunnel and then burying it, with trees, shrubs and hedgerows planted on top to blend in with the surrounding countryside.
The tunnel structure will be made from more than five thousand giant concrete segments, made at a specialist precast factory in Derbyshire, and assembled on site by HS2’s main works contractor, EKFB – a team made up of Eiffage, Kier, Ferrovial Construction and BAM Nuttall.
Applying lessons from the construction of the latest French high-speed lines, EKFB opted for this modular approach — instead of a traditional process of pouring the concrete on site — to boost efficiency and cut the amount of embedded carbon in the structure.
Greatworth is one of five ‘green tunnels’ that are being built on phase one of the HS2 project, which is designed to improve links between London, Birmingham and the north, boost the economy and free up more space on the existing rail network for freight and local services.
Readers can download photos of the first completed tunnel ‘arches’ and see images showing how it will look once complete and see the first arches installed for Greatworth Tunnel here.
Also available for download is broadcast quality animation showing what green tunnels are, and how they are built.
Image courtesy of HS2.