HS2 has completed the 3,130 tonne second Wendover Dean Viaduct deck slide.
New footage shows the latest stage of a complex year-long project, in which almost half a kilometre of bridge deck will be slid into place above Buckinghamshire’s Misbourne Valley.
Engineers slid the 3,130-tonne structure 270 metres over a 20 hour period last week, using Teflon pads to reduce friction.
The deck of the Wendover Dean Viaduct, which will stretch for 450 metres when complete, is being assembled in three stages. The railway will also be on a slight gradient, meaning the deck is being pushed slightly uphill. The finish point will be approximately 1.8 metres higher than the start point.
HS2 Ltd Senior Project Manager Ben Sebastian-Green said: “It’s great to see so much progress at Wendover Dean Viaduct over the last few days – with all the piers and the first three slides now done.
“The narrow site has always made it a challenging place to build, but I’m really impressed by how everyone’s pulled together to get us where we are today.”
The Wendover Dean Viaduct is the first major railway bridge in the UK to be constructed with a ‘double composite’ structure, which uses less carbon-intensive concrete and steel than a more traditional design. The approach will cut the carbon footprint of the structure by around half.
The hollow ‘double composite’ structure uses two steel beams sandwiched between two layers of reinforced concrete, which creates a more efficient super strong span.
HS2’s Small Dean, Westbury, Lower Thorpe and Turweston viaducts will also follow this approach.
The Wendover Dean Viaduct’s beams are made of ‘weathering steel’ which will naturally fade over time to match the natural tone of the surrounding countryside. It will be supported by nine evenly-spaced piers, some of which are up to 14 metres high and all of which are now complete.
The last few months have also seen significant progress at other major HS2 viaducts at Birmingham Curzon Street and Delta Junction in North Warwickshire.
HS2 is building more than 500 bridging structures in total, from small road bridges to record-breaking constructions such as the Colne Valley Viaduct, which will be the longest in the UK.
Image credit: HS2