Scale effects of small diameter cylindrical inclusion in sand

摘要

Tests consisting of applying an increasing torque to vertical rough inclusions embedded in sand have been carried out on the ZII Bochum centrifuge. In order to check size and scale effects, behavior of those inclusions of different diameters and 200 mm length have been investigated under 100 and 50 g (with and without overconsolidation). Experimental displacement-shear stress relationship has been obtained. Results are discussed and compared for each test. Scale and consolidation effects are pointed out and discussed. Considering failure as corresponding to the maximum torque, it appears difficult to obtain at failure simple similarity for both a force and displacement. It is shown that modeling of cylindrical inclusion in sand in centrifuge can lead to problems of scale effects. Due to the very small size of these elements, usual similarity relationships cannot be perfectly reached.