A new section of the A41 connecting Aylesbury and Bicester reopened on Monday following a weekend shutdown to facilitate its diversion over a newly constructed bridge spanning the HS2 route near Waddesdon.

The A41 overbridge, constructed just north of the current road over two years, spans 80 metres over a cutting designed to accommodate HS2 rail services between London and the West Midlands.

It is among the 500 bridging structures of the HS2 project, encompassing everything from minor footbridges and drainage culverts to pioneering ‘green bridges’ for wildlife, and massive viaducts like the Colne Valley Viaduct, which holds the record as the UK’s longest.

It is also the second structure to be completed by HS2 builders this month, with the first railway viaduct on the route being completed a few weeks ago.

The installation of new roundabouts on both sides of the bridge will enhance safety by facilitating smoother traffic flow from Blackgrove Road and Waddesdon Hill onto the A41. Additionally, the footpath running adjacent to the current road south of Waddesdon has been lengthened.

The bridge’s construction employed a ‘top-down’ approach, where the deck was assembled at ground level, supported by piles that were driven deep into the earth.

Subsequently, the soil was removed to create the cutting.

The bridge was constructed using twenty-one U-shaped precast concrete beams to create its three spans, with the deck and wing walls being cast in situ.

The complete road realignment stretches 2.6km, encompassing seven sets of utility diversions.

Although the bulk of the work was carried out without interrupting traffic flow, several weekend closures were necessary for utility works and to securely integrate with the current road.

In the future, two additional weekend closures are anticipated to finalize the kerbs, road surfacing, and part of the road marking.

“Once complete, HS2 will dramatically improve journeys between our two largest cities while freeing up space on the existing rail network for more freight and local services.

But it’s also important that we keep communities connected while we deliver this transformative project. That’s why smaller structures like the A41 overbridge are so important and I’d like to thank everyone in our team and across the supply chain who worked so hard to get it built and open to the public. It hasn’t been an easy job and I’d like to also thank the local community for their patience during the road closures.”

HS2 Ltd’s Project Manager, Vlad Kolev

The bridge construction and road realignment project was completed by HS2’s main works contractor, EKFB, which consists of Eiffage, Kier, Ferrovial Construction, and Bam Nuttall.

The new road surface on the bridge was installed over the weekend, and traffic began using the new alignment from 5:30 am on Monday.

The temporary roundabout at the entrance to the HS2 A41 site compound will be dismantled at a later date after the completion of HS2 construction.