HS2 slides bridge into position over M42

HS2 moves 12,600 tonne bridge over M42 a record 163 metres using innovative construction method.

HS2 is celebrating a world-first with its latest feat of engineering, after 'sliding' a 12,600-tonne bridge over the M42 in Warwickshire.

Around 450 construction workers from HS2's Midlands contractor Balfour Beatty VINCI (BBV) slid the bridge a record 163 metres, to position it across the motorway.

The site team worked around the clock for 40 hours during the dramatic operation to position the Marston Box bridge.

Using this innovative method dramatically cut disruption to road users, in line with HS2's plan to reduce the impact of construction on local communities.

Mike Lyons, HS2 civils delivery director, said: “This is the first box slide of its kind over a motorway in the UK, and we believe it’s also the world’s longest slide, so it’s a great achievement for HS2 as we quickly approach peak construction.

"It’s fantastic to celebrate another big milestone for a project that is already providing work for almost 30,000 people today, and in the future, it will encourage people to use zero carbon public transport.”

The 86 metre-long structure, developed by Mott MacDonald and Systra on behalf of BBV, was built on land next to the motorway over a six-month period. It comprises a base, three walls and a top slab.

The sliding mechanism, designed by specialist civil and structural engineering company Freyssinet, allowed the box to be pushed into place over the motorway on a guiding raft, over a distance of 163 metres.

It is believed this makes it the world’s longest box slide.

On completion, the whole structure will be around 190 metres long, and will carry HS2 over the motorway as it heads north to Crewe, or on its southward journey as it loops into Birmingham Curzon Street or continues straight on to Interchange Station in Solihull, Old Oak Common Station and London Euston.

Once built, the railway bridge will connect to Dunton Wood Embankment to the south and the Birmingham and Fazeley Canal Viaduct, which crosses the heritage canal, to the north.

This construction method, which allowed it to be moved into place in one movement, meant only two one-week closures of the motorway over a 12-month period, including over the quiet festive period.

Sasan Ghavami, Balfour Beatty VINCI’s construction director for the project said: “We’re extremely proud to have successfully delivered the world’s longest box slide. It’s a huge achievement for our project team and everyone connected with Balfour Beatty VINCI."

The box slide operation is part of HS2’s 550,000 square metre site at Kingsbury, where over 1,000 people are currently working.

Around 6,800 people are already employed in HS2’s construction in the West Midlands, with thousands more jobs supported through the wider supply chain.

HS2 and its contractor Balfour Beatty VINCI (BBV) has worked in partnership with National Highways to deliver this intricate operation.

Frank Bird, National Highways senior network planner, said: “We’ve been working collaboratively with HS2 for the past 18 months to ensure the operation ran smoothly and to help keep disruption to a minimum for drivers. The installation of the new Marston Box bridge is a significant milestone in the HS2 project and it’s great to see it finally in place.”

Click here to watch dramatic footage of the bridge slide.

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