HS2 milestone: box structure installed under major road

Altrad RMDK provided a full suite of temporary works solution for the project. Image: Altrad RMDK

The 14,500-tonne structure, built adjacent to the A46 carriageway, was later pushed into place beneath the road, something that reportedly avoided up to two years of major roadworks.

At 42m wide, it forms a critical component of the HS2 route and involved the heaviest bridge move ever carried out in the UK.

Specialist contractor Freyssinet designed a guiding raft and jacking system that enabled the structure to be moved at a rate of 6.5m per hour. More than 800 tonnes of temporary works equipment was deployed at peak, including night shifts to maintain progress.

Altrad RMDK provided a full suite of temporary works solutions, including Superslim Soldiers, Alform beams and inclined Tubeshor ground shoring props. These supported the structure during over 4,300m³ of concrete pours, including inclined walls, tulip piers and the deck.

“We pride ourselves on being a one-stop shop for temporary works solutions,” said Stuart Grant, senior sales representative at Altrad RMDK.

Sharon Liu, sub agent at Balfour Beatty Vinci, added, “Altrad RMDK’s ability to deliver and manage the right equipment on a tight schedule, and their hands-on expertise, directly contributed to the success of the bridge slide – helping us reopen the road 30 hours ahead of schedule.”