DEM: Biaxial compression 3. The effect of grain size on fracturing

These experiments investigate the effect of grain size and relative strength on fracture development during compression using a Discrete Element Model. The media contains ~24,000 elements with radii ranging between 0.25 and 0.5 of a unit. Grains are coloured according to their breaking strain which is between 0.025 and 0.05 of their initial separation (see figure 3, Finch, Hardy, Gawthorpe, 2004 and figure 2, Pichel et al. 2017, doi below). The breaking strain is the distance beyond which a bond is broken between a pair of elements. Grain sizes are defined at the start of the experiment where an element is chosen at random. Its neighbours within a defined distance (R) are then assigned a similar breaking strain with minor variation (