Design and build contract for the development of York House courtyard to accommodate a new two storey underground car park for around 80 cars. Tony Gee was commissioned to design the geotechnical and structural elements of the work.
Top-down construction was employed to reduce the environmental impact on residents through concealment of the underground works. This technique also provided a very stiff support system that helped minimise ground movements and permitted use of a flexible, cost effective sheet pile retaining wall due to the high stiffness of the combined support system.
The differential heave profile across the structure necessitated piles that effectively pinned the basement at depth within the London Clay.