Table 2 Numerical simulation parameter settings18,19.
Number | Parameter symbol | Parameter name | Value | Unit |
|---|---|---|---|---|
1 | \(\:{k}_{0}\) | Initial permeability | \(\:1\times\:{10}^{-12}\) | \(\:{m}^{2}\) |
2 | \(\:{\phi\:}_{0}\) | Initial porosity | 0.1 | 1 |
3 | \(\:E\) | Elastic modulus | \(\:4\times\:{10}^{9}\) | \(\:Pa\) |
4 | \(\:\nu\:\) | Poisson’s ratio | 0.3 | 1 |
5 | \(\:{K}_{s}\) | The elastic modulus of coal matrix | \(\:9\times\:{10}^{9}\) | \(\:Pa\) |
6 | \(\:c\) | Cohesion | \(\:1\times\:{10}^{6}\) | \(\:Pa\) |
7 | \(\:{\sigma\:}_{t}\) | Tensile strength | \(\:2\times\:{10}^{6}\) | \(\:Pa\) |
8 | \(\:\theta\:\) | Internal friction angle | 30 | ° |
9 | \(\:\sigma\:\) | Crustal stress | \(\:10\times\:{10}^{6}\) | \(\:Pa\) |
10 | \(\:\mu\:\) | Viscosity of water | 0.00298 | \(\:Pa\:s\) |
