Evolution of the Force Chain Topology with Increasing Particle Non-Sphericity in 2D and 3D Systems

That irregular distribution of inter-particle forces in compressed or sheared granular matter has become known as force chains. The irregular distribution influences the macroscopic behavior of granular matter and beyond that has been shown to lead to eddy like structures in slow granular flow and to influence the width of shear bands in granular flows.[1,2] Despite these implications the development of force chains has been primarily studied for systems of spherical particles, employing both experiments as well as simulations.[3–5] Do to the opacity of granular matter the experimental investigations have been focused on two dimensional systems.[6]

Particles occurring in natural and industrial processes are rarely perfect spheres or limited to two dimensional systems. In this work we use a discrete element method (DEM) to investigate the evolution of force chains for particle shapes varying from spheres to non-spherical and even concave shapes such as crosses and jacks. We further vary the system dimensions to represent 2D as well as 3D systems. The results provide insight into the inter-particle force distribution of real systems and allows for a better understanding of the macroscopic behavior of granular matter.

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