Victoria Station Upgrade
Victoria Station Upgrade (VSU) is a £741 million upgrade of the busiest station on London Underground and one of the UK’s strategic transport infrastructure assets. The Victoria Line is the busiest London Underground line with more than 100 million passengers per year. In order to minimise impact to the already stretched transport infrastructure, key requirements by the client were: the new works do not affect the safe operational of the Underground; road traffic is kept moving, including the buses and taxis using the Victoria Terminus Place bus station, and; the works do not disrupt the many utilities, or neighbouring businesses and residents, which include two of the capital’s longstanding Grade II listed theatres. These requirements made the tunnelling works technically complex, with intricate geometries to suit the exceptionally constrained site.
Tunnel excavation was undertaken at shallow depths, with an axis approximately 10m below ground and clearances below 50mm from essential LU assets in places. Construction had to take place at the interface between London clay and overlying, water-bearing terrace gravels, requiring more than 2000 interlocking jet grout columns to be constructed prior to tunnelling. The jet grout columns and Sprayed Concrete Lining (SCL ) excavations were undertaken beneath main roads in the heart of London and beneath the Grade II listed Victoria Palace theatre. Tunnelling is proposed using Sprayed Concrete Lining (SCL) techniques and the station is required to remain fully operational throughout the works.
Dr Bedi has been involved in this project since early design conception in 2007, through detailed design and currently working alongside the main works contractor supervising the construction on site as the Senior SCL Engineer. During the design phase, Dr Bedi was engaged in and leading the design of the tunnels, shafts and junctions as well as undertaking impact assessment of the existing tunnels due to adjacent excavation. During construction Dr Bedi worked alongside with the designer, construction team and London Underground to not only assure, but also optimise, the tunnels design and construction process on this complicated station upgrade. The work undertaken on this project led to the development of a novel method of constructing and breaking out new cross-passages in to live London Underground platform and passenger tunnels, and use of BIM in inferring the extent of untreated ground ahead of the tunnel face.