A UK-first technique used to construct HS2 River Tame West Viaducts

The project is being delivered by HS2’s main works contractor for the West Midlands, Balfour Beatty VINCI (BBV) who are constructing 90km of HS2 between Long Itchington in Warwickshire to the centre of Birmingham and on to Staffordshire.

This is the first of nine viaducts that will use this method of construction which uses pre-cast concrete segments produced at an HS2’s bespoke outdoor factory near Lea Marston. The team have recently celebrated producing the 1,000^th segment out of a total 2,742 segments needed to complete the viaducts.

The River Tame West Viaducts carry three rail tracks in total, made up of one single track viaduct and one double-track viaduct.

The two River Tame West Viaducts cross the River Tame near Water Orton and join the Curdworth Box, which will take the new line over the existing Birmingham to Derby railway.

The structure has been under construction since 2023 beginning with the 20 piers to support the viaducts, the first spans of the three-track section were completed in Spring 2024. This first phase involved placing the segments onto two 42 metre truss beams, moving them into place with a skidding trolley, and securing them by post-tensioning techniques.

The giant cantilever structure has been built, using a 22-metre-high mast, including temporary post-tensioning cable stays and a 14-metre-high swivel crane.

The crane lifts and installs one concrete segment into place at a time, to complete each 45-metre span length. The permanent post-tensioning tendons are then stressed to allow the removal of the temporary cable stays, leaving the permanent structure securely in place. The same process is repeated between each pier until all of the spans are complete.

A total of 2,500 concrete segments will be moved into place using this specialist technique. All the deck segments are due to be in place by August 2026. The same process will be used to build a total of nine viaducts in the Delta Junction.

Reaching this incredible milestone is a wonderful moment for the Mott MacDonald SYSTRA Design Joint Venture team. It brings to life the innovation, collaboration and commitment of everyone involved on the project and marks a significant part of the journey to bring high speed trains between Birmingham and London.

Ian Johnson, Project Director, MMSDJV

HS2’s Delta Junction is a triangular section of line, enabling trains to travel between London and Birmingham, Birmingham and Manchester, and direct between London and Manchester without stopping at Birmingham. It is made up of embankments, cuttings and a total of 13 viaducts taking high speed tracks over motorways, local roads, existing rail lines, rivers and floodplains. The viaducts include 6 precast segmental viaducts, 4 composite viaducts and 3 low viaducts.

Find out more about our work on HS2 here.