Research Article
The Mechanism and Application of Deep-Hole Precracking Blasting on Rockburst Prevention
Table 2
Classification of bursting proneness of coal.
| Classification | Type I | Type II | Type III |
| Bursting proneness | None | Weak | Strong | Indexes | | | | Duration of dynamic fracture ()/ms
| > 500 | 50 < ≤ 500 | ≤ 50 | Elastic strain energy index () | < 2 | 2 ≤ < 5 | ≥ 5 | Bursting energy index () | < 1.5 | 1.5 ≤ < 5 | ≥ 5 | Uniaxial compressive strength ()/MPa | < 7 | 7 ≤ < 14 | ≥ 14 |
|
|