Micro-, Meso- and Macroscale Properties of Granular Packings under Cyclic Compression

We subject a set of photoelastic particles to repeated cyclic compression. As expected, the load applied to this granular system is focused along force chains which form a network of connections throughout the system. Since a jammed granular system is overconstrained, this force network is not unique and differs for each compression cycle. Using our open source PeGS software we reconstruct the vectorial contact force for all interparticle contacts in the system for thousands of realizations of the force network. We show that the probability distribution function of the contact forces collapses on a single curve for all realizations and packing fractions when scaled by the mean contact force. We further show that fluctuations of the pressure on each particle in the system correlate to the particle's betweenness centrality value extracted from the geometric contact network. Thus we can relate the contact network mesostructure to the individual particle pressures and the statistics of the interparticle forces to the global volume fraction.