A Lagrangian integration point finite element method for large deformation modeling of viscoelastic geomaterials

We review the methods available for large-deformation simulations of geomaterials before presenting a La-grangian integration point finite element method designed specifically to tackle this problem. In our ELLIPSIS code, the problem domain is represented by an Eulerian mesh and an embedded set of Lagrangian integration points or particles. Unknown variables are computed at the mesh nodes and the Lagrangian particles carry history variables during the deformation process. This method is ideally suited to model fluid-like behavior of continuum solids which are frequently encountered in geological contexts. We present benchmark examples taken from the geome-chanics area