Discrete element modelling of normal compression of clay

The discrete element method (DEM) has only rarely been used to simulate clay, due to difficulties in modelling clay particle shape and capturing the various particle interactions. This paper presents a new approach to simulate clay in three dimensions using DEM, featuring realistic particle shape and a new straightforward interaction law, which is able to reproduce all well-known characteristic platelet interactions. By varying the interactions between the platelets (including both the ‘edges’ and ‘faces’), it is possible to account for a range of environmental conditions. Simple sedimentation and one-dimensional compression tests are presented, which correctly reproduce the expected behaviour, confirming the validity of the model. Particle-scale analysis reveals the influence of the platelet interactions on the bulk behaviour, and it is also shown that platelet aggregation appears to lead to a fractal distribution of aggregated ‘stack’ sizes as a means of space filling.