4D model tests of CPT pile design performance in chalk

Open-ended (OE) pile field tests performed in low density chalk have demonstrated a unique installation response not widely observed in other geomaterials. This has encouraged the development of new CPT based design methods (ICP-18). Recently, A campaign of small-scale pile and CPT tests on intact soft rock materials has been undertaken using a new multi-axis loading frame offering new observations on this unique behaviour. Similarities in model and field scale numerical tests suggest that the effects of stress-state may be less marked in the case of structured materials. Although scaling and stiffness issues certainly exist, the performance of the ICP method is trialed at small-scale enabling a new discussion on the applicability of small-scale pile tests in rock, scaling aspects and the changes intact rock fabric undergoes during subject to pile insertion which are revealed using X-ray tomography.