Pioneering Percussion Driven Earth Anchors (PDEA®) for 40 Years


Pembury Hospital, Royal Tonbridge Wells, Kent – UK

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Project Overview

Construction of a new £225 million hospital for the Tonbridge and Maidstone NHS Trust presented a cramped site with limited working space. Slope stabilisation was specified, allowing steepening of a slope to facilitate works. Laing O’Rourke’s design team were keen to explore the use of Percussion Driven Earth Anchors (PDEA®) in the sandy ground encountered on site.


Testing revealed that the sand encountered on site had a very high internal angle of friction, enabling a relatively small anchor to be used while still achieving a high load. An Indemnified Design was prepared by the Platipus Geotechnical team, containing anchor specification, installation depth, and surface finish. Following which the document was reviewed and approved by Laing O’Rourke and Gifford.

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