Abbey Pynford were approached by the local authority to underpin the corner of a building which suffered from severe ground movement.
A piled cantilevered scheme was proposed to avoid extensive internal works and to accommodate the extreme depth (5m+) of desiccation in the clay based subsoil. The scheme was designed by our in house design team and comprised of 300mm diameter SFA piles installed to a depth of 19m, with a Klemm 702. We used temporary casings to the top 4m to overcome the made ground and seal into interface with the London Clay below.
The piles and ground beams were carefully configured to ensure that the scheme did not conflict with the extensive services and the existing structure.
The 600mm2 reinforced concrete ground beams were installed on 110mm clayboard to provide a heave void beneath. The existing walls were supported on Pynford Stools to allow the masonry to be removed and the beams / antiheave precautions to be installed above the existing foundation. A continuous beam was formed within the existing wall to span between the ends of the cantilevered ground beams.
Just a quick note to commend you and your teams hard work on the Wendover Woods project. From the beginning of the order process right through to design, construction and signing off the works it was a pleasure working alongside Abbey Pynford on this challenging project.
Michael Hayes, Senior Site Manager, Kier Construction