Archi-texture of inertial granular flows

E Azéma & F Radjai

By means of extensive 3D numerical simulations, we analyze the microstructure of dense granular flows and its relation with shear strength as a function of the inertial number I representing the ratio of particle relaxation time to shear time. We find that the shear strength increases with I only as a consequence of increasing anisotropy of the contact network whereas the anisotropy of force chains remains nearly constant. The contact network undergoes topological transitions, and beyond I ≃ 0.25 the force chains break into clusters immersed in a background “soup” of floating particles. We show that this transition coincides with the divergence of the size of fluidized zones.


Sheared packings for different values of the Inertial Number : I 0.1(a), I 0.25(b) and I 0.6(c)
Floating particles are in grey and non-floating are in purple