HS2 is a new high-speed railway forming the backbone of Britain's transport network. Ferrovial, part of EKFB, designs and constructs two central sections across a 50-mile stretch.
Among the viaducts of the scheme, two types stand out for their innovation and sustainability: precast viaducts and double composite viaducts.
a) Precast viaducts (Thame Valley and Edgcote):
The design presents high levels of prefabrication: precast substructure, girders and deck, including state of the art global experiences. The number of U-girders has been reduced from four to two, and the in-situ diaphragm on piers has been eliminated, providing continuity between spans with post-tensioned bars. This approach increases quality, safety, and sustainability by building in a controlled environment with fewer resources.
b) Double composite viaducts:
Five viaducts have been optimized using a double composite bridge superstructure, the first major railway bridges in the UK with this design. The solution consists of two steel girders between two layers of reinforced concrete, creating a lightweight hollow span with high structural capacity. Composite bridge structures make use of the intrinsic advantages of steel beams and concrete deck acting in tension and compression respectively to minimise material and increase the efficiency. These benefits are further maximised in the case of a double composite. This design uses less concrete and steel, reducing the carbon footprint. The slender design minimizes the visual impact on the landscape, essential for protected areas like the Chilterns.
Both viaduct types demonstrate a commitment to innovation, sustainability, visual impact and excellence in engineering.
HS2 UK Viaducts. Innovation and Sustainability
Integrated Systems
