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The Sandstone surrounding rock caving and deterioration development table.
| Operating hours (day) | Number of particles lost from the surrounding rock | Shedding width (cm) | Shedding depth (cm) |
|---|---|---|---|
| 10 | 0 | 0 | 0 |
| 30 | 3 | 12 | 6 |
| 60 | 15 | 13 | 8 |
| 90 | 27 | 15 | 8 |
| 180 | 42 | 32 | 10 |
| 360 | 78 | 43 | 15 |
