Influence of particle shape on shear stress in granular media

Emilien Azéma (1) , Farhang Radjai (2) , Robert Peyroux (1) , Gilles Saussine (3)

1 LMGC - Laboratoire de Mécanique et Génie Civil
2 PMMG - Physique et Mécanique des Milieux Granulaires
3 Physics of Railway Systems, Innovation and Research Departement of SNCF

We analyze the contact and force networks in a dense confined packing of pentagonal particles simulated by means of the contact dynamics method. The particle shape effect is evidenced by comparing the data from pentagon packing and from a packing with identical characteristics except for the circular shape of the particles. A surprising observation is that the pentagon packing develops a lower structural anisotropy than the disk packing. We show in this work that this weakness is compensated by a higher force anisotropy that leads to enhanced shear strength of the pentagon packing. With the polygonal shape of the particles, the strong force chains are mostly composed of edge-to-edge contacts with a marked zig-zag aspect.

Mots clés: anisotropy; granular; polygon; shear stress

Domaines: Mécanique des matériaux [physics.class-ph]; Mécanique des matériaux [physics.class-ph]

Emilien Azéma, Farhang Radjai, Robert Peyroux, Gilles Saussine. Influence of particle shape on shear stress in granular media. Traffic and Granular Flows, 2007, Paris, France. p497-505. ⟨hal-00172122⟩