First massive ‘Lego block’ beams lifted for HS2’s pioneering Thame Valley Viaduct

HS2 has started positioning the initial set of 72 massive beams that will support the Thame Valley Viaduct's deck, marking the first instance in the UK where all major components are produced off-site.

Posted on: October 31st 2023    •    Posted in: PACADAR UK, Partners, Sustainability

At the Thame Valley Viaduct Aylesbury site, engineers utilised two colossal cranes to position 25-meter-long, 90-tonne beams atop the viaduct piers.

Departing from the typical use of multiple smaller beams per span, the design team chose a more straightforward structural solution featuring just two larger hollow U-shaped beams, resulting in a lighter and simpler construction. This innovative design, inspired by Spain’s high-speed rail viaducts, significantly reduces the structure’s carbon footprint by cutting down on carbon-intensive concrete and steel by about a third.

The viaduct was designed by HS2 Ltd’s main works contractor, EKFB – a team made up of Eiffage, Kier, Ferrovial Construction and BAM Nuttall – working with specialist on-site construction partner, FC Civils Solutions.

PACADAR UK based at London Thamesport produced the 68 massive concrete piers, each weighing 42 tonnes, with the first 36 already installed since early summer.

This off-site manufacturing approach not only expands contract opportunities and supply chain jobs across the UK but also employs 200 individuals, including apprentices and graduate engineers, to contribute to both the viaduct and tunnel segment production for HS2’s London tunnels.