Research Article
Experimental Study of Gangue Layer Weakening with Deep-Hole Presplitting Blasting
Table 1
Proximate analyses of the sample.
| | Lithology | Thickness (mm) | Compressive strength (MPa) | Average density (g/cm3) | Similar material ratio (cement: sand: coal powder: lime: gypsum: water) |
| | Roof sandstone | 330 | 3.2 | 1.52 | 0 : 7:0 : 0.5 : 0.5 : 0.8 | | Floor sandstone | 120 | 3.2 | 1.52 | 0 : 7:0 : 0.5 : 0.5 : 0.8 | | Coal seam | 120 | 0.6 | 0.83 | 0 : 5:2 : 0.7 : 0.3 : 0.8 | | Gangue layer | 30 | 6.0 | 1.73 | 1.6 : 3.5 : 0:0 : 0.2 : 0.6 |
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