Tunnelling complete at the Victoria Station Upgrade

Congratulations to our Victoria Station Upgrade team on reaching one of the project’s major milestones recently.

They have constructed approximately 300m of sprayed concrete lined tunnels in an area were previous tunnelling projects have resulted in ground collapses, with as little as 100mm clearance to existing operational London Underground assets in places.

Before tunnelling could begin, the water-bearing gravels had to be treated in what became the largest use of jet grouting for tunnel construction in the UK. The design involved six points at which the new tunnels break into the existing station tunnels, and the team was the first to incorporate ‘propless’ connections in the design to remove the need for any temporary propping in the station at these points. This maximised operational space throughout the works, which is essential to a station that handles more passengers than Heathrow Airport each year.

Christmas 2014 saw a crucial piece of the works completed, when the team constructed the roof of the tunnel connecting the two ticket halls within 0.6m clearance from the District and Circle lines running rails.

Craig Prangley, Project Director, said “Innovation and teamwork has been at the heart of all of these achievements. Well done to all of the Victoria Station Upgrade team.”

Once complete, the £700m upgrade will transform journeys for over 2 million passengers each week by providing a new North ticket hall, doubling the size of the existing South ticket hall, and providing step-free access for passengers.