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 , **evesque@mssmat.ecp.fr**

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, j_{w}} 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