Acoustic characterization of slow compaction dynamics in noncohesive disordered granular media
Résumé
Noncohesive disordered granular media are well known to exhibit very complex behaviour when being excited by mechanical solicitations. This work presents our studies of the slow dynamics in granular media undergoing a compaction process. The characterization of slow dynamics is performed by an acoustic probing of the packing after mechanical solicitation. With this aim we have built a special setup to increase the density of the granular medium and to probe its elastic properties by the acoustic resonance method. Elastic modulus and acoustic dissipation are extracted from the frequency and the quality factor of resonances. To clarify how the contact properties between grains modify the acoustic parameters during the compaction we have also studied the influence of the temperature and the humidity on the acoustic measurements. Interpretations of the experimental observations are proposed. This work is supported by project "STABINGRAM" ANR-2010-BLAN-0927-03.
Origine : Fichiers éditeurs autorisés sur une archive ouverte