Convection  and  Motion  in  2-d  Embankments Under  Cyclic  Boundary  Conditions


P. Evesque: Lab MSSM, UMR 8579 CNRS, Ecole Centrale Paris, 92295 Châtenay-Malabry, France ,


Abstract: The motion of grains in a 2d embankment under periodic horizontal forcing is studied theoretically using Coulomb-type modelling. Periodic conditions are used to determine the inclination of the free surface. It is shown that no periodic solution can be found in some domain of the bulk- and wall- friction parameters {j, jw} larger than 30°. When a stable periodic solution exists, we show that the finite amplitude of motion leads to generate a flow localised at the free surface, near the bulldozer wall and in the yield band; this may enforce a bulk convection too. At last, we argue why bulk convection is generated when the periodic solution is not stable. Results are compared to experimental data.

Pacs # : 5.40.-a ; 5.45.-a ; 45.70.-n ; 62.20.-x ; 83.50.V

poudres & grains 14 (3), 54-80 (Sept. 2004)