Research Article
Study on Dynamic Evolution of Roof Crack and Support Timing of Secondary Tunneling for Large Section Open-Off Cut in Deep Mines
Table 2
Calibration of mechanical properties of rock strata and coal seams used in the model.
| Rock strata | Matrix properties | Contact properties | Density (kg/m3) | E (GPa) | (GPa/m) | (GPa/m) | Cohesion (MPa) | Friction angle (°) | Tensile strength (MPa) |
| Sandy mudstone | 2450 | 3.42 | 180 | 54.2 | 2.7 | 32 | 1.23 | Fine sandstone | 2550 | 5.40 | 278.5 | 83.6 | 3.4 | 35 | 1.59 | Coal | 1400 | 0.79 | 150.2 | 46.1 | 1.4 | 30 | 0.52 |
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