University College London Hospitals (UCLH)
University College London Hospitals (UCLH) are developing a new Proton Beam Therapy (PBT) facility in the heart of London. The PBT unit will treat some of the most difficult cancers in children and adults. The facility is being housed in a purpose-built centre on Grafton Way and Huntley Street and includes one of the deepest basements ever constructed in London with an excavation depth of 28.5m below street level. The basement works have been undertaken by Bouygues and specialist contractors McGee and Fayat Piling.
To undertake this mammoth basement in the heart of London required exceptional skill and experience in deep excavation design and the construction team appointed ByrneLooby as their design specialist. ByrneLooby prepared the detailed design and reinforcement of the deep diaphragm wall along with the design of the foundation piling. The diaphragm wall solution consisted of 1020mm thick panels installed to a depth of 32m below ground level. ByrneLooby advised on the optimum construction sequence to achieve an efficient solution and to minimise ground movements.
The diaphragm wall was constructed from the existing basement level, requiring ByrneLooby to carefully assess the forces from the existing basement retaining walls and to incorporate a king post support system into the top of the diaphragm wall. The congestion during the diaphragm wall construction illustrates the challenges of redeveloping such sites in the centre of a busy city. ByrneLooby developed the construction sequence with the main contractor during their tender for the project.