Temporary casings are regularly used in the construction of rotary bored piles, to support the pile bore in potentially unstable soils and also to prevent water ingress from loose or water logged soils. The preferred method of removal of casing is by pulling with a crawler crane. However, the magnitude of force generated, particularly during the initial stage of casing extraction, is unknown. This paper describes a series of 50g centrifuge tests designed to model the casing and surrounding soil during extraction by crane. In each test different sized model casings were installed at various embedment depths into a layer of clay overlain by a well-graded sand to provide an array of data. The depth of granular overburden was varied from 60 mm to 120 mm to allow for assessment of the influence of this material on the extraction force whilst the casing sizes modelled 900 mm and 1800 mm prototypes
