Numerical analysis of spudcan penetration into sand over uniform clay

![CDATA[The installation of mobile jack-up platforms remains hazardous because of the potential for uncontrolled punch-through failure. Seabeds of sand overlying clay, or stiff clay over soft clay, are problematic because the embedding spudcan pushes the strong layer of soil into the underlying softer layer. Both experimental and numerical approaches have been adopted in previous studies to assess punch-through potential and to understand the factors affecting the failure mechanism. In this paper, the entire penetrating process of a spudcan is simulated using a large-deformation finite element approach – the Coupled Eulerian-Lagrangian method in the commercial package Abaqus. The numerical approach is first compared with centrifuge model test data for uniform clay, uniform dense sand and loose sand over uniform clay. Results from a series of parametric studies of spudcan penetration into sand over uniform clay sites are then described. The dependence of the penetration behaviour on the friction angle and dilation behaviour of sand, the undrained shear strength of the underlying clay and the normalised sand layer thickness are also discussed.]]