David Richards, Ken Rush Associates, and Michael Turner, Applied Geotechnical Engineering. This paper was first published in GE’s August 2005 issue.
Permanent ground anchors are an efficient and cost effective way of providing restraint for retaining structures, involving minimum disruption at surface level during construction. The 1970sand 1980s saw a marked growth in the use of ground anchored systems with design lives in excess of 60 years. However, the next cycle of redevelopment on sites where they were first used is now beginning, and the implications and constraints imposed by these anchors are becoming apparent.
This paper describes the design and construction of piled foundations which were installed at Chandlers Wharf, Erith, Kent in the proximity of permanent ground anchors as part of a residential development of a derelict industrial site alongside the River Thames.
An initial desk study located not only original drawings and records but also traced the anchor designer. This helped to develop a detailed understanding of the particular anchors used at Erith and the constraints these would impose on the design of new piling. Aspects of the construction works are also described, including monitoring and testing of the ground anchors.