title: Transition dynamics and magic-number-like behavior of frictional granular clusters.
abstract: Force chains, the primary load-bearing structures in dense granular materials, rearrange in response to applied stresses and strains. These self-organized grain columns rely on contacts from weakly stressed grains for lateral support to maintain and find new stable states. However, the dynamics associated with the regulation of the topology of contacts and strong versus weak forces through such contacts remains unclear. This study of local self-organization of frictional particles in a deforming dense granular material exploits a transition matrix to quantify preferred conformations and the most likely conformational transitions. It reveals that favored cluster conformations reside in distinct stability states, reminiscent of "magic numbers" for molecular clusters. To support axial loads, force chains typically reside in more stable states of the stability landscape, preferring stabilizing trusslike, three-cycle contact triangular topologies with neighboring grains. The most likely conformational transitions during force chain failure by buckling correspond to rearrangements among, or loss of, contacts which break the three-cycle topology.
authors.affiliation: Department of Mathematics and Statistics, University of Melbourne, Parkville, Victoria 3010, Australia. atordesi@ms.unimelb.edu.au
authors.forename: Antoinette
authors.initials: A
authors.lastname: Tordesillas
authors.forename: David M
authors.initials: DM
authors.lastname: Walker
authors.forename: Gary
authors.initials: G
authors.lastname: Froyland
authors.forename: Jie
authors.initials: J
authors.lastname: Zhang
authors.forename: Robert P
authors.initials: RP
authors.lastname: Behringer
mesh_terms: D003102:Colloids / Q000737:chemistry*; D003198:Computer Simulation; D017276:Friction; D008956:Models, Chemical; D008958:Models, Molecular; D044367:Phase Transition; D012212:Rheology / Q000379:methods*; D033081:Shear Strength
chemical_list: D003102:Colloids