On the application of a discrete model to the fracture process of cohesive granular materials

We present a two-dimensional model of heterogeneous cohesive frictional solids where the material structure is idealized by a discrete granular particle assembly. Our discrete model is composed of convex polygons which are linked together by simple beams accounting for cohesive effects. Varying its parameters the model naturally interpolates between a continuous solid state and a discontinuous dry granular state of the material. We performed simulations of the quasi-static uniaxial loading with two different boundary conditions, and shearing of a solid. To provide a geometrical description of the damage state, and of the microscopic fracture events, different characteristic quantities will be introduced and their relevance will be examined. The results obtained from simulations are in satisfactory agreement with experimental observations.