In a first for UK engineering, an 11,000-tonne curved concrete box has been successfully pushed under the East Coast main line at Werrington near Peterborough.
A team from Network Rail and its contractors reached this major milestone in the project to build a new tunnel that will enable slower-moving freight trains to dive underneath the passenger route and use an adjacent line northwards.
Newly released time-lapse footage shows the 155-metre curved concrete box tunnel, which is heavier than the Eiffel Tower, being pushed into place at just 150cm per hour, using four hydraulic jacks.
This is the first time that a curved concrete box has been installed using this industry-leading engineering technique in the UK.
It took nine days, but using this cutting-edge technique avoided hundreds of hours of passenger disruption on this vital part of the East Coast Main Line and meant that services could continue running throughout.
Teams removed three of the tracks, lifted the overhead wires and dug out spoil from the site. Once the tunnel was eventually underneath, they then put everything back in place ready for regular services to resume. The work was carried out safely, in line with Government Covid guidance.
Paul Rutter, director of Network Rail’s East Coast route, said: “Our teams have completed this challenging piece of engineering in a creative way, which also allowed a reduced train service to continue for those who still had to travel.
“Over the nine days, we’ve made major progress on this vital project which will bring faster, more reliable journeys for passengers on the East Coast Main Line.
“I’m so proud that this project has shown itself to be one which is industry leading and that our teams have had the opportunity to use this new technique for the first time in the UK on one of the country’s most famous railway lines.”
The next stage of the project at Werrington involves work to install two new tracks inside the new tunnel and the associated signalling system, ready for it to come into use at the end of 2021.