A numerical investigation of scale effects on the behavior of discontinuous rock

In numerical simulations of mining induced problems, it is not possible to represent discontinuities at all length scales. However, all length scales are coupled, so the homogenisation process and the selection of what discontinuities must be represented explicitly should be rigorous. To investigate some homogenisation concepts for mine problems, the load-deformation response of some discontinuous rock masses at an example mine have been simulated using Explicit, Finite Element models. The intent of the analysis was to investigate the effects of specimen size and confining stress on strength, dilation and comminution. The analysis is used as a basis for a discussion of some preliminary ideas and concepts for deciding what length scale of structures need to be included in numerical models of mining deformation.