Large strain finite element analysis of sand: model, algorithm and application to numerical simulation of tire–sand interaction

Based on a review of several existing models for the elastic responses of geomaterials, a new nonlinear elastic law is suggested. A fully implicit return mapping algorithm for non-associative elastoplastic models of the geomaterials is presented within the regime of large strains. This algorithm is formulated in the principal axes. Algorithmic tangent moduli are derived. A modified critical state model in conjunction with the new nonlinear elastic law is implemented into the general purpose finite element software MARC, using the proposed algorithm. Furthermore, the tire–sand interaction is numerically simulated, employing the modified model and the algorithm.