Numerical study of crack propagation in an indented rock specimen

Indentations were simulated to investigate the stress evolution characteristics of the indentation process using the discrete element method (DEM). The maximum principle stress and the shear stress were recorded by applying measurement circle logic. The results indicate that an increase in indentation force contributes to the concentration of shear and tensile stresses at the crack tips. The indentation force decreases because of the crack propagation, which is accompanied by stress dissipation at the crack tips. In addition, tensile and shear-tensile cracks, propagating in different modes, have been observed. The results show that the shear-tensile cracks are responsible for chip formation.