Table 3 Coal-rock material parameters.
Material | Density (kg/m3) | Elastic modulus (MPa) | Poisson's ratio | Unidirectional strength (MPa) | Internal friction angle(°) | Firmness coefficient | |
|---|---|---|---|---|---|---|---|
Compression | Tensile | ||||||
Coal | 1280 | 2010 | 0.28 | 12 | 0.3 | 20.50 | 1.5 |
Aluminum mudstone | 2460 | 3620 | 0.25 | 34 | 1.2 | 33.26 | 3.5 |
Limestone | 2610 | 18,300 | 0.22 | 52 | 5.23 | 38.82 | 6.8 |
Hard inclusion | 2600 | 21,500 | 0.19 | 64 | 7.17 | 42.14 | 8.4 |
