We observe experimentally densification, induced by tapping, of saturated granular packings. Packings are prepared by mixing single size glass beads with Newtonian oils having different viscosities. Even though effective buoyancy is reduced, packings prove to density under tapping. Moreover, their density evolution is found qualitatively similar to the one previously observed with dry packings. On the other hand, they also exhibit distinctive properties: their initial density is lower due to the hydrostatic thrust, their final density is higher due to lubrication and viscous drag slows down densification. As a consequence, the density logarithmic time dependence observed with dry packings had to be modified introducing a density-dependent parameter in order to describe accurately experimental data.
展开▼
