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Figure 10

Change of FoS value and size of the slope failure surface with different scenarios of UG operation by 2025_
| Slope in 2025 | FoS value | |||
|---|---|---|---|---|
| Before UG | After UG | |||
| Scenario I | Scenario II | Scenario III | ||
| Left slope wall | 1.75–2.0 | 1.75–2.0 | 1.5–1.75 | 1.75–2.0 |
| Right slope wall | >2.5 | >2.5 | >2.5 | 2.0–2.25 |
Mechanical properties of rock mass in the studied region [33]_
| Type of rock mass | Bulk modulus K (GPa) | Shear modulus G (GPa) | Cohesion c (MPa) | Fiction angle φ (°) | Tensile strength σt (MPa) | Density ρ (kg/m3) |
|---|---|---|---|---|---|---|
| Mudstone | 2.31 | 1.54 | 1.87 | 30 | 1.34 | 2620 |
| Claystone | 2.23 | 1.34 | 2.05 | 26 | 1.14 | 2600 |
| Anthracite | 2.17 | 1.36 | 2.14 | 27 | 1.22 | 1500 |
| Conglomerate | 4.76 | 3.57 | 3.23 | 28 | 2.27 | 2510 |
| Sandstone | 3.91 | 2.46 | 3.56 | 28 | 1.96 | 2600 |
Strength parameters of the fault in the studied region [33]_
| Strength parameters | Friction angle (°) | Cohesion (kPa) | Tensile strength (kPa) |
|---|---|---|---|
| Value | 12–20 | 3.4–4.4 | 0 |
Hypotheses for calculating thickness of the caved zone_
| Author, year | Thickness of caved zone |
|---|---|
| Peng and Chiang, 1984 [38] | (2–10)t |
| Bai et al., 1995 [39] | 100t/(c1g+c2) |
| Mazurkiewicz et al., 1997 [40] | t/(kr−1) |
| Heasley, 2004 [41] | (10–18)t |
| Biliński, 2005 (simplified) [42] | (nkst)/(0.05Rc0.5+0.02) |
| Wang et al., 2017 [43] | (3–4)t |