Site excavated for arrival of Tunnel Boring Machine

One of HS2’s largest construction sites in the Midlands is being prepared for the arrival of a

Tunnel Boring Machine (TBM) that will be launched next summer.

Starting at Long Itchington, the TBM will dig under the adjacent wood to create a one-mile twinbore tunnel, before the route then heads north for Curzon Street station in Birmingham.

Sixty staff are currently on site, including student engineers and apprentices, but it’s expected that number will reach 7,000 across the Midlands over the next two years.

Work currently involves creating a large, deep excavation with 250,000m3 of material removed and deposited locally, where it will form environmental embankments for the railway.

The TBM, built by Herrenknecht in Germany, is due on site early next year. The tunnel will be 9-10 metres in diameter, and it’s expected that boring will be complete by mid-2022.

Also on this stretch of Phase 1 is Bromford Tunnel, as well as 100 bridges, 35 viaducts, 36 cuttings and 70 bridge structures.

BBV Joint Venture (Balfour Beatty Group and VINCI Construction) is the contractor for this part of Phase 1.

HS2 Delivery Director David Bennett explained: “The tunnel in this location goes under Long Itchington Wood specifically to preserve a section of ancient woodland.

“This forms a key element in how we are managing environmental impacts through the design of the railway. Along with 32 miles of tunnel, HS2 will also be criss-crossed by over 150 bridges and underpasses on Phase 1, including 16 specially designed ‘green bridges’ covered in planting. And a green corridor alongside the route will integrate HS2 into the landscape.”

At the peak of construction on the whole of Phase 1, ten TBMs will work 24 hours a day, seven days a week. Weighing up to

2,200 tonnes, each 160-metrelong machine will bore and line the tunnels as they drive forward at speeds of up to 15 metres per day.

■ The first TBMs for HS2, which will bore the ten-mile twin-bore Chiltern Tunnel (the longest on Phase 1), arrived in the UK from Germany on December 8 (as this issue of RAIL went to press).

The 2,000- tonne machines, named Florence and Cecilia, will be reassembled, tested and commissioned before they begin work.

HS2 LTD. A view across the construction site at HS2’s Long Itchington Wood tunnel. The headwall is visible below the wood, while in front of it, in a cutting, is the launch pad for the Tunnel Boring Machine.