Analysis of Fracture Characteristics of Ore Rock Based on GMTS Criterion

In this paper, the Tongkaiyu ore-rock is taken as the research object, aiming to analyze the fracture characteristics of the mixed type I, II and I–II faults in ore-rock by using the appropriate fracture criterion, and analyze the fracture development mode. Considering the non-singular term (T stress) in the formula of stress field sequence at crack tip, the generalized maximum tangential stress (GMTS) criterion is established, which is consistent with the boundary conditions of the central straight Brazilian disk (CSTBD) specimen. Through CSTBD splitting test and three-dimensional particle flow code (PFC3D) numerical simulation, the Angle between the central direct joint and the loading direction was changed, and the fracture toughness and fracture development law of type I, type II and type I–II mixed fracture were obtained. The theoretical and simulation results show that, compared with the maximum tangential stress (MTS) criterion, the GMTS criterion has an advantage in judging the fracture characteristics of mixed types I, II and I–II in ore rock.