ABSTRACT
Since original Coulomb publication (1773), many investigations have tracked the role of physical friction inside of granular media macroscopic behavior. In spite of remarkable advances like Rowe stressdilatancy theory (1962), reworked by Horne (19651969), the subject still lacks an achieved clarification. A new approach of this matter, from elementary contact up to macroscopic scale, can be based on statistical physics ruling energy dissipation (Frossard, 2001). These energy dissipation physics are based upon the original concept of “internal actions”, Figure 1, materialized by a tensor formed by the product of internal forces and internal movements. Its trace is the usual rate of mechanical work developed by internal forces; elementary friction laws occur to induce a key relation between its eigenvalues: the energy-dissipation equation.
