Résumé
The free surface which results from the filling of a container by a dry granular material, takes the shape of a heap. This shape is induced by the particle properties like their size and their restitution coefficient but also by their kinetic energy induced by the filling conditions. The stabilization of the intergranular contact network inside the heap leads to the formation of a local stress field. For five wheat-based powders of same origin but with contrasted properties, beds are formed in a 2D semi-confined cell with a funnel of small outlet (localized source). Captures of the bed free surface are realized from pictures taken at different filling states. The local vertical force is measured in the center of the cell at different depths in the heap. This work highlights a correlation between the local vertical force profile and the shape of the heap during the filling. Two modes of force distribution can be distinguished and classified according to a parameter of uniformity and the gap from a pseudo-hydrostaticity. These distinctions are linked to the different shapes of the heap, quasi-layering or dune. Our experimental study demonstrates that the history of the powder filling directly impacts on the resulting local force profile.