Microscopic features of cohesive granular media

We investigate the textural properties of 2D cohesive granular media simulated by the molecular dynamics method involving simple contact laws with adhesion. Our extensive numerical results with samples of 4000 particles suggest a transition between two regimes depending on the surface energy. In the first regime, the adhesion gives principally rise to a geometrical rearrangement of the system. The coordination number increases and saturates around four as the surface energy is increased. In the second regime with high surface energies, the principal phenomenon is a force reorganization such that a fraction of contacts become tensile and the system gets partially crystallized. This evolution is corroborated by the statistics of forces and contact directions in the system.