Stability, deformation and variability of granular fills composed of polyhedral particles

Quezada Juan Carlos (1, 2) , Breul Pierre (3) , Saussine Gilles (2) , Farhang Radjai (4)

1 LMGC - Laboratoire de Mécanique et Génie Civil
2 R&D - SNCF - Département recherche et développements
3 MIST - Laboratoire de micromécanique et intégrité des structures
4 PMMG - Physique et Mécanique des Milieux Granulaires

By means of extensive contact dynamics simulations, we investigate the mechanical equilibrium and deformation of a granular material composed of irregular polyhedral particles confined between two horizontal frictional planes. We show that, as a consequence of mobilized wall-particle friction force at the top and bottom boundaries, the transient deformation induced by a constant vertical load is controlled by the aspect ratio (thickness over width) of the packing as well as the stress ratio. The transient deformation declines considerably for increasingly smaller aspect ratios and grows with the stress ratio. From the simulation data for a large number of independent configurations, we find that sample-to-sample fluctuations of the deformation have a broad distribution and they scale with the average deformation. We also analyze the evolution of particle connectivity during settlement and with the applied force. The face-face and edge-face contacts between polyhedral particles concentrate strong force chains with a growing proportion as a function of the applied force.

Mots clés: granular matter; polyhedral particles; fluctuations; transient deformation; shear strength; Coulomb friction; contact dynamics

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

Quezada Juan Carlos, Breul Pierre, Saussine Gilles, Farhang Radjai. Stability, deformation and variability of granular fills composed of polyhedral particles. Physical Review E : Statistical, Nonlinear, and Soft Matter Physics, 2012, 86, pp.031308. ⟨10.1103/PhysRevE.86.031308⟩. ⟨hal-00689731⟩