Simulation of Suction Caisson Penetration in Seabed Using an Adaptive Mesh Technique

Abstract

This paper reports results of a numerical investigation into the suction caissons penetration in sand. A 3D finite element model is used for this purpose. The water saturated soil domain is modelled as a two-phase medium, consisting of soil skeleton and pore-water phases. Nonlinear behavior of the solid phase is described by means of a bounding-surface plasticity model. The caisson itself is modelled by solid elements and non-porous linear elastic properties. The soil-soil and soil-caisson interactions along the penetration path are modelled with a master/slave contact algorithm using contact surfaces and a frictional contact interface. A re-meshing technique is also used to avoid excessive distortion of the finite elements along the caisson-soil penetration path.The model was first substantiated against laboratory test data. The numerical model was found to present acceptable agreements with the experimental measurements. The verified model was then used to study the influence of parameters such as soil internal friction, penetration speed and adaptive mesh schemes on the installation behavior of suction caissons in sands.