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Roof pre-splitting parameters for the 10204 gob-side entry retained.
| Parameters | Value |
|---|---|
| Pre-splitting depth | 20 m |
| Dip to the goaf angle | 15° |
| Borehole spacing | 500 mm |
| Borehole diameter | 50 mm |
| Explosive type |
No.3 emulsion explosive |
|
Charge quantity in a single borehole |
11.7 kg |
| Detonation method | Indirect priming |
| Sealing length | 3.5 m |
|
Explosive quantity in a sound |
117 |
