Résumé
An explicit relation is developed to describe the capillary force in a doublet of two grains of different sizes as a function of the physical and geometrical characteristics. In particular, it depends on the inter-particle distance and on the volume of the liquid bridge. The modeling of capillary force is validated by experiments performed over a capillary doublet. From this theoretical modeling, we propose a local law of interaction by capillary force taking into account contact and friction between particles as well as the rupture of the liquid bridge. This local law is then implemented in a 3D code based on Discrete Element Method (DEM). This code is used to compute the macroscopic behavior of granular materials involving local interactions as capillary forces.