APPLICATION OF A SPLITTING FRACTURE MODEL TO THE SIMULATION OF ROCK INDENTATION SUBSURFACE FRACTURES

A two-dimensional fracture model based on micro-fracture mechanics is applied to the Hertzian indentation stress field to simulate subsurfac e fractures in an axi-symmetrical plane. The simulation of fracture de velopment reveals quantitatively the effects of loading force, mechani cal properties of the rocks, and original micro cracks on the formatio n of subsurface fractures. The distribution patterns of the subsurface fractures are determined by the magnitudes and trajectories of the in dentation stresses. Lateral confinement prohibits the fracture develop ment. Simulations of the subsurface fractures in granite and marble ar e in good agreement with the indentation experiments.