Research Article
Design and Application of Blasting Parameters for Presplitting Hard Roof with the Aid of Empty-Hole Effect
Table 5
Charge parameters of blast holes.
| | Holes | Hole depth (m) | Elevation (°) | Vertical height (m) | Sealing length (m) | Sealing material | Charge weight (kg) | | Upper | Lower |
| | Roadside | L | 40.0 | 29 | 22.5 | 19.9 | 14 | 9 m stemming | 6 m expansive cement | 36 | | R | 38.2 | 24 | 18.6 | 16.0 | 14 | 9 m stemming | 6 m expansive cement | 24 | | Roof | 17.0 | 90 | 18.0 | 6 | 6 m stemming | 16.5 |
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