Fracture reveals clustering in cohesive granular matter

Franco Tapia (1) , Stéphane Santucci (1) , Jean-Christophe Géminard (1)

1 Phys-ENS - Laboratoire de Physique de l'ENS Lyon

We report an experimental study of the morphology of fractures in cohesive granular materials. Cohesion is introduced by equilibrating the grains with a humid atmosphere. The setup allows to produce a controlled crack in a thin layer of a glass beads assembly, and observe with an extremely high resolution the edge of the fracture at the free surface of the layer. The detailed multi-scale analysis of the fracture profile reveals the presence, in the bulk of the material, of clusters of grains whose size increases monotonically with the relative humidity. These results are important because the formation of clusters, resulting in a heterogeneity of the cohesion force, governs the mechanical properties of cohesive granular matter in contact with a humid atmosphere.

Domaines: Physique Générale [physics.gen-ph]

Franco Tapia, Stéphane Santucci, Jean-Christophe Géminard. Fracture reveals clustering in cohesive granular matter. EPL - Europhysics Letters, 2016, 115 (6), pp.64001. ⟨10.1209/0295-5075/115/64001⟩. ⟨hal-01417941⟩