On the use of discrete element method for multi-scale assessment of clay behavior

This paper presents a review of the physics controlling various forces between clay particles, and the incorporation of these forces in a DEM contact model in PFC3D. This contact model was validated against a 1-D consolidation experiment from the literature, and the clay microstructure was assessed. It was found that this contact model can predict the compression index and the pore size evolution with the increase of stresses. However, it is recommended that the compression curve from DEM simulation be normalized using the minimum void ratio and the corresponding maximum vertical stress to match the experimental results. Furthermore, the paper presents an analysis of the microstructure regarding the evolution of the pore sizes and particles orientations under 1-D consolidation extending the data available in the literature about the use of DEM to microscale analysis.