Reorganization of a packing of discs previous to the avalanche

M. A. AGUIRRE, A. MEDUS, M. MANCUSO, A. CALVO AND I. IPPOLITO

Stuttgart, Germany

Conferencia; Fifth International Conference on the Micromechanics of Granular Media, Powder and Grains 2005; 2005

Rearrangements of different sizes were found to take place not only on the free surface but also in the bulk of a bidimensional packing of discs slowly tilted until the system completely looses its stability and an avalanche occurs. Larger rearrangements are studied in detail for  thick systems (height @16d, being d the diameter of discs in the packing). Analysis of the change of the packing contact network indicates that the system gets more disordered as it evolves to its stability threshold where the avalanche begins.