Research Article
Gob-Side Entry Retaining Technology with Advanced Empty Hole Butterfly-Shaped Weakening in Three-Soft Coal Seam in China
Table 2
Extreme values of stresses at different hole spacings.
| Hole spacing (L/cm) | Single hole | L = 0.5D | L = 1.0D | L = 2.0D | L = 3.0D | L = 4.0D | L = 5.0D |
| Maximum stress (MPa) | 4.40 | 5.43 | 4.76 | 4.53 | 4.48 | 4.40 | 4.40 | Minimum stress (MPa) | 0.51 | 0.49 | 0.51 | 0.51 | 0.51 | 0.51 | 0.51 |
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