Development of layered models for geotechnical centrifuge tests

Centrifuge modelling is an established technique for investigating the ground response to complex and non-standard geotechnical events. These models are usually made from re-formed soil, allowing for comparisons with naturally occurring soil deposits. Clay models are formed by mixing clay powder and water into a slurry. This slurry is placed within a container and loaded to create a uniform stiff clay model. However, there is a fundamental disparity between this process and the deposition of natural soils, because natural soil is deposited in layers creating a unique structure. This structure is important for modelling true soil behaviour because some essential soil properties (such as permeability, stiffness and strength) are not identical in all directions. Currently, there are limited methods for creating layered soil samples. This paper describes the development of a new procedure for creating layered centrifuge models with structure – leading to potentially more representative models of naturally occurring ground