Site size: 5 units / 167m2
Duration: 14 weeks
Client: Aoca Engineering Consultants & Sedgwick Group
These five new properties in London were suffering from ground movement due to historic tree root influence. We were approached by the consulting structural engineers to provide an underpinning solution to stabilise them and protect against any future heave.
A Piled Raft Solution
Due to the internal load-bearing walls requiring underpinning it was decided that a piled raft solution would be optimal, as this replaces the beam and block floor that needed to be removed to facilitate the underpinning.
To facilitate the original development, various trees were removed in the vicinity which, due to the plasticity of the clay subsoil resulted in the heave and damage to the properties. To allow for any future disturbance we installed our reinforced concrete raft on Clayboard to create a void beneath the raft, isolating the structure from any ground movement.
Supporting the Structure
All the temporary works required were designed and carried out in-house. The existing structure was supported on Pynford Stools to allow the raft to be installed above the existing foundation. We removed the stalls internally, preventing any external excavations and reinstating the surface finishes.