Crushing or grain fragmentation is a very complex phenomenon that involves several scales. At the atomic and molecular scale, dislocations or heterogeneities in the material structure may cause over-stresses that, at the end, may prompt fissures and the failure of the material.
Scaling up, at the grain scale, we may find complex stress distributions within a particle when loaded with an arbitrary set of forces. If, additionally, we include the shape and size variability of a granular material, such as sand or ballast, we face a quite difficult phenomenon to tackle.
We developed a model to simulate grain fragmentation in which we consider that the grains are composed of an homogeneous material and a set of potential fragments. For the moment we are not interested in the atomic or molecular aspects of fragmentation. We break particles as function of the stresses between the potential fragments of a grain.
We started with the most simple case. An individual grain compressed between two walls. The following video shows an example of our simulations :).
Do you want to see more?
Check our paper here!