Research Article
Analysis and Application on Controlling Thick Hard Roof Caving with Deep-Hole Position Presplitting Blasting
| Vibration velocity (cm/s) | Damage degree corresponding to different vibration speeds | Medium sandstone remark |
| <24 | Rock mass without fracture | – | 26–63.4 | Low development of fractures in rock stratas | 31–47 cm/s | 63.5–254 | The tensile crack is serious in rock stratas with radial cracks locally developing | 48–170 cm/s | >255 | Rock mass is completely broken | >171 cm/s |
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