Résumé
The Contact Dynamics method is a numerical technique for computing the dynamical motion of collections of bodies submitted to the unilateral constraints of mutual non-interpenetrability, taking into account dry friction in the case of contact and also the velocity jumps which may arise from collisions. The essential nonsmoothness of the problem is faced without resorting to any regularizing approximation such as artificial repulsion or artificial viscosity. The method is illustrated here by the simulation of a rectilinear shear zone occurring in a slowly strained granulate. The concept of Internal Moment is introduced in order to analyse the transmission of forces.