The UK’s High Speed Two (HS2) has completed the civil engineering phase at the Long Itchington Wood Tunnel in Warwickshire, England, the first deep tunnel on the high-speed route to reach this stage.
The one-mile-long twin-bore tunnel, which will carry the railway into the West Midlands, has seen the completion of elements such as three cross passages, concrete finishing works, base slabs, and emergency and maintenance walkways.
This progress sets the stage for the internal fitting out of the tunnel with the necessary systems such as power, track, and signalling, to run the high-speed line.
In total, 27.4 miles of the route between London and the West Midlands will be encompassed by deep, twin-bore tunnels.
The construction of the tunnel is a collaborative effort by HS2’s main works contractor for the West Midlands, the Balfour Beatty VINCI joint venture (JV), with 380 individuals having contributed to the project since its inception.
Balfour Beatty VINCI tunnelling director Jules Arlaud said: “The scale of this achievement is enormous. A dedicated workforce of around 380 people have worked tirelessly over the past five years to reach this latest phase of construction, where the tunnels are now fitted with three cross passages and the concrete finishing works, base slabs, and walkways are also complete.”
“Throughout this project, our expert tunnelling team have installed a total of 1,582 concrete rings across both tunnels, with each ring made from eight 2m-wide segments, each weighing up to eight tonnes [t].”
Other twin-bore tunnels on HS2 are progressing as well, with the Bromford Tunnel expected to complete tunnel drives this year, internal works ongoing for the Chiltern Tunnel, and the Northolt Tunnel’s first drive that was concluded in December last year.
The Euston Tunnel is also preparing for the launch of two tunnel-boring machines (TBMs).
The Long Itchington Wood Tunnel’s construction began in June 2020, using a 125m-long TBM named ‘Dorothy’, after Nobel Prize winner Dorothy Hodgkin.
Excavation was completed by March 2023, with approximately 750,000t of material produced and reused for building embankments along the railway’s route.
Designed to minimise environmental impact, the tunnel lies 30m below ground, preserving ancient woodland and avoiding local villages.
The tunnel’s progress is part of the ongoing construction of HS2 between the West Midlands and London, which now supports more than 31,000 jobs.
Recent developments in the West Midlands include the completion of HS2’s first viaduct at the Delta Junction and progress on a new green bridge near Kenilworth.
Additionally, the construction of the base slab for the Old Oak Common HS2 station in London was completed earlier this month.
