| Damage Mechanism |
| ||||||
| Cause of Rock―Burst Damage | Damage Severity | Thickness m | Weight kN/m2* | Closure† mm | Ve,‡ m/s | Energy kJ/m2 | |
| Bulking without ejection | Rock with high stress and small amount of stored stress energy | Negligible Reasonable Foremost | <0.25 <0.75 <1.5 | <7 <20 <50 | 15 30 60 | <1.5 <1.5 <1.5 | Not critical Not critical Not critical |
| Bulking causing ejection | Rock with high stress with substantialextrastress energy | Negligible Reasonable Foremost | <0.25 <0.75 <1.5 | <7 <20 <50 | 50 150 300 | 1.5 - 3 1.5 - 3 1.5 - 3 | Not critical 2 - 10 5 - 25 |
| Ejection by remote seismic event | Seismic energy transfer to jointed or broken rock | Negligible Reasonable Foremost | <0.25 <0.75 <1.5 | <7 <20 <50 | <150 <300 >300 | >3 >3 >3 | 3 - 10 10 - 20 20 - 50 |
| Rockfall | Inadequate strength, forces increased by seismic acceleration | Negligible Reasonable Foremost | <0.25 <0.75 <1.5 | <7 g/(a + g) <20 (a + g) <50 (a + g) | - - - | - - - | - - - |