Layer | Fill | Outline |
---|
Map layers
Theme | Visible | Selectable | Appearance | Zoom Range (now: 0) |
---|
Fill | Stroke |
---|---|
Collaborating Authors
Results
Abstract: Fragmentation strongly influences the interlocking hang-up phenomena, a common occurrence in conjunction with cohesive arching around draw points in block caving systems. This work presents a brief numerical study of the influence of fragmentation on interlocking hang-up phenomena. Fragment interaction and breakup are simulated numerically by combining the impulse-based energy tracking method (ETM) and the finite element method (FEM) in three dimensions. Numerical tests with varying size of ore fragments are carried out. The breakage of rock fragments is modeled during the entire simulation and the influence of fragmentation is investigated in terms of productivity and the efficiency of draw point extraction. Simulation results with fragmentation are compared to non-fragmentation numerical tests. It is observed that with fragmentation, 1.93% and 2.57% more volume of ore fragments are extracted before hang-up when the initial diameter of ore fragments is 5.775 m and 7.5 m, respectively.
Abstract: Nonlinearity and hysteresis are two key features of elastic rock deformation. This behavior can be attributed to the presence of cracks and crack-like voids. The hysteretic behavior of rocks is related to the concept of unrecovered energy. Two main processes lead to the existence of unrecovered energy in the sliding crack model: (i) the work of frictional forces and (ii) the strain energy trapped in the solid. In this paper, a theoretical and numerical analysis will be presented to extend the work of David et al. [1] to consider 3D penny-shaped cracks. A 3D finite element analysis is used to evaluate the sliding crack model numerically. In this approach, the penalty method is used to simulate the contact behavior of the crack faces. The stick-slip condition of the crack faces is simulated by employing the constitutive frictional law of Amontons. The results show that no residual strain is developed in the body containing randomly oriented cracks if one assumes a uniform stress over all the crack cells. The energy loss is therefore equal to the work of frictional forces on the crack faces.
- Geology > Geological Subdiscipline > Geomechanics (1.00)
- Geology > Rock Type (0.94)