Research Article
Thick-Anchored Dual-Layer Locking Supporting Technique in Gob-Side Entry Driving with the Narrow Pillar: A Case Study
Table 2
Comparison of bolt performance parameters commonly used.
| Parameters | Diameter (mm) | Length (m) | Yield strength (MPa) | Tensile capability (kN) | Elongation (%) | Pretension (kN) |
| Rebar bolts | 22 | 2.2~2.5 | 500 | 240 | 20 | ≤60 | Flexible bolts | 21.8 | 3.5~4.3 | 1600 | 560 | 7 | 250~300 |
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