In a UK first, engineers working on the HS2 project slid a 4,600-tonne viaduct across the M6 without closing the motorway, leading to ‘significantly reduced' disruptions for drivers.
Taking 17 hours, the operation marked the conclusion of a three-stage process used to construct and install the 315-metre East deck of the M6 South viaduct, designed to carry the HS2 line.
Previously, projects similar to this have required the closing of the carriageway, but in this instance, Balfour Beatty VINCI (BBV) coordinated with National Highways to develop what they referred to as a ‘fully restrained' process that allowed the final section to be slid into place whilst traffic continued below.
Whilst the project did require the initial closure of the M6 overnight between Junctions 4 and 5, as well as the weekend closure of the M42 slip road, the main carriageway was able to remain in use whilst the viaduct was pushed across at 13 metres per hour.
Russell Luckhurst, the BBV engineer leading the delivery of the project, said: ‘We're all feeling a huge sense of pride after sliding a 4,600-tonne viaduct into its final position this weekend. The third and final slide of the East deck viaduct was delivered over a live motorway for the first time in the UK, making this achievement even more special.
‘Using this ‘fully restrained' technique meant we were able to keep disruption to an absolute minimum. Our focus will now turn towards the neighbouring West deck viaduct, which will be launched in multiple phases throughout 2026, as well as the East deck finishing works.'
