HS2 is cutting carbon emissions by up to two-thirds on five viaducts using a new "double composite" design. This method significantly reduces concrete and steel compared to traditional approaches.
The design adds a concrete bottom to steel beams, creating a hollow box structure. This allows for a thinner overall structure, reducing the use of high-emission materials like steel and concrete.
The new design has been implemented on viaducts in Buckinghamshire, Oxfordshire, and West Northants. It offers several benefits including:
- Lower Carbon Footprint: The amount of embedded carbon in the viaducts is reduced by 52% to 66%.
- More Efficient Bridges: The design allows for longer spans between piers, needing fewer support structures.
This project demonstrates collaboration between HS2, its construction partners, and suppliers. It paves the way for future sustainable infrastructure projects.
Here are some additional details:
- The Westbury viaduct is one example, with its deck being slid into place in three stages.
- This innovative approach is being used on over five structures across HS2's central section.
- HS2 is building over 500 bridges in total, including the record-breaking Colne Valley Viaduct.
HS2 Ltd’s Head of Civil Structures, Tomas Garcia, said:
“HS2 will improve journeys between Britain’s two biggest cities while freeing up more space on the most overcrowded parts of the existing mainline for more local services. Construction is well underway, and it’s great to see the lessons learnt from Wendover Dean, rolled out to four other major structures.
“The double composite approach – which combines the strength of steel in tension and with concrete in compression – has huge potential to cut carbon in construction by enabling more efficient bridges. I look forward to seeing them completed and hope the lessons we have learnt can be successfully applied to other bridge projects across the UK.”
Image credit: HS2
