A discrete element model to describe failure of strong rock in uniaxial compression

A bonded particle model is investigated by means of an extended Discrete Element Method with respect to failure of strong rock in uniaxial compression. A coordination number based inflation scheme is presented, which generates isotropic sphere packings that are featuring a higher average coordination number than conventional procedures. A progressive failure model is proposed, which promotes crack propagation and localization and allows adjusting brittleness of fracture. Failure of the granular solid is discussed in detail. The fracture process is studied in dependence of the introduced failure models. The influence of particle size and bond strength distributions, particle numbers, particle layering in finite sphere packings and end constraints is addressed. Comparison to published experimental results reveals that many of the observed features of rock failure are reproduced.