U&M Group

Piled Raft Underpinning

Monday, March 4th, 2013 AT 04:12PM

  • Type of work: Repairs
  • Location: Herne Bay
  • Duration: 6 Weeks
  • Ground conditions: Clay

Subsidence House Repairs- Herne Bay  Piled Raft Underpinning

Our customer had a detached four bedroom property in Herne Bay that had suffered damage resulting from subsidence due shrinkage of the clay subsoil.

The front corner of the property was so badly cracked and distorted that the corner of the property had to be taken down. Prior to its removal, our engineers designed a temporary scaffold with needle beams to support the roof above, while the underpinning was being undertaken.

Once the wall was down and the property stripped out, we installed a piled raft using twenty four 200 mm diameter Open Auger Piles to an average depth of 10m. These piles were then all linked by a 225mm thick reinforced concrete raft which then extended through all the walls so that the whole property was supported on the new piled raft.

Full anti-heave precautions were included to the upper 4 meter section of each pile, and a 150mm clear void was formed beneath the raft by casting the raft on 160mm Clayboard.

Upon completion of our underpinning works, we issued a 12 year Defects Insurance Guarantee.