Abstract: Based on the cavity expansion theory, the influences of the geometric parameter (edge angle), the rock mechanical parameters (compressive strength and Poisson's ratio) on the radius of elastic-plastic interface in rocks under wedge cutting conditions are studied. The results show that the smaller the blade angle, the larger the damaged area and the larger the elastoplastic radius when the contact width between the blade and rock is constant. When the other factors remain unchanged, the increase of the Poisson's ratio or the increase of the compressive strength leads to a decrease in the radius of elastoplastic interface. The sensitivity of the three factors is studied by the sensitivity analyzing method. Under a certain contact width, the blade angle has the most significant influence on the damaged area. A numerical model of the penetration of indentation is developed by using the software ABAQUS. The numerical results show that the changes of the blade angle can significantly influence the spatial position of the point with the maximum tensile stress and the direction of minimum gradient.

Key words: wedge cutter, cavity expansion theory, edge angle, parameter sensitivity analysis