Research Article
The Numerical Simulation of Hard Rocks for Tunnelling Purposes at Great Depths: A Comparison between the Hybrid FDEM Method and Continuous Techniques
Table 5
Input material parameters for all numerical models.
| | Model type | Parameter | Value |
| | FEM-Hoek–Brown (peak and residual values are the same) | UCS (MPa) | 200 | | | Young’s modulus (GPa) | 69 | | | Poisson’s ratio | 0.22 | | | GSI | 80 | | | | 0.50093 | | | | 0.10837 | | | | 15.6653 | | DFN parameters (joints are assumed purely frictional) | Friction angle (°) | 35 | | | Normal stiffness (GPa/m) | 690 | | | Shear stiffness (GPa/m) | 69 |
| | FEM-DISL (subscripts and denote peak and residual values) | UCS (MPa) | 200 | | | Young’s modulus (GPa) | 69 | | | Poisson’s ratio | 0.22 | | | | 0.25 | | | | 0.033 | | | | 1 | | | | 0.75 | | | | 0 | | | | 9 | | DFN parameters (joints are assumed purely frictional) | Friction angle (°) | 35 | | | Normal stiffness (GPa/m) | 690 | | | Shear stiffness (GPa/m) | 69 |
| | FDEM | Young’s modulus (GPa) | 65 | | | Poisson’s ratio | 0.18 | | | Viscous damping factor | 1.0 | | | Normal contact penalty (GPa·m) | 650 | | | Tangential contact penalty (GPa/m) | 650 | | | Fracture penalty (GPa) | 650 | | | Friction coefficient | 1.7 | | | Cohesion (MPa) | 50 | | | Tensile strength (MPa) | 10 | | | Mode I fracture energy (N/m) | 300 | | | Mode II fracture energy (N/m) | 1900 | | DFN parameters (joints are assumed as purely frictional) | Discontinuity friction coefficient | 0.7 | | | Normal contact penalty (GPa·m) | 650 | | | Tangential contact penalty (GPa/m) | 650 | | | Fracture penalty (GPa) | 50 |
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