Coupling Discrete Elements and Micropolar Continuum through an Overlapping Region

Interfacial mechanics between granular materials and deformable solid bodies involve large shear deformation and grain motion at the interface. To resolve such granular physics at the grain scale in contact with the deformable solid, but in a computationally tractable manner, we present a concurrent multiscale computational method. As a simple problem to verify the method, a one-dimensional string of glued elastic discrete elements is overlapped with a linear elastic micropolar continuum finite element implementation. The overlap coupling is enabled by the bridging scale decomposition method, but now with rotational degrees of freedom (dof) in addition to axial and transverse displacements. The paper presents the preliminaries of coupling discrete element regions and micropolar finite element regions for eventual simulation of granular soil-tire/tool/geosynthetic/penetrometer applications, wherein eventual three-dimensional discrete element formulation and finite strain micromorphic continuum finite element is required.