Nonlocality in granular complex networks: Linking topology, kinematics and forces

Abstract

Dry granular systems respond to shear by a process of self-organization that is nonlocal in nature. This study reveals the interplay between the topological, kinematical and force signature of this process during shear banding in an sample of angular sand. Using Level-Set Discrete Element simulations of an in-situ triaxial compression experiment, and complex networks techniques, we identify communities of similar topology (cycles), kinematics (vortex clusters) and kinetics (force chains), and study their cooperative evolution. We conclude by discussing the implications of our observations for continuum modeling, including the identification of mesoscale order parameters, and the development of nonaffine kinematics models.