“…For example, some authors have considered effects of pore size and spatial distribution at different scales [25,12,7,29,58,59,47,44,51,43]; others have studied the void shape effects [14,15,22,26,27,46]. Different matrix properties have been investigated: Mises-Schleicher type matrix [23,11,28,56,54], Green type one [47,48,52,51,55,53] and Drucker-Prager type one [21,4,16,24,57,44,11,49] have also been investigated. On the other hand, some studies have focused on the effects of mineral grains in heterogeneous materials.…”