Simulating the Caisson Penetration in Sand Using a Critical State Based Soil Model

The penetration of a caisson redistributes the soil stress state and influences the interactions between the foundation structure and the soil. However, few finite element studies on caisson foundations take the influence of installation into account. In this paper, a numerical simulation considering large deformations is presented to analyze the behavior of a caisson foundation during the installation phase. A newly developed elastoplastic model incorporating nonlinear elasticity, a plastic hardening law and the critical state concept is adopted and implemented into the finite element code ABAQUS. To solve the large deformation problem, the finite element method is combined with the Smoothed Particle Hydrodynamics method (SPH). The penetration area of the soil is simulated using SPH particles while classical finite elements are used elsewhere. Results demonstrate that the SPH method coupled with a critical state based model is a useful tool to analyze the behavior of caisson foundations, their failure modes and the soil-bucket interactions.