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Relationship between seismic intensity and physical quantities of vibration.
| Seismic intensity | Natural earthquake |
Maximum vibration speed of blasting (cm/s) | ||
|---|---|---|---|---|
| Acceleration (cm/s2) | Speed (cm/s) | Displacement (mm) | ||
| VII | 50–100 | 4.1–8.0 | 21.-4.0 | 6.0–12.0 |
| VIII | 100–200 | 8.1–16.0 | 4.1–8.0 | 12.0–24.0 |
| IX | 200–400 | 16.1–32.0 | 8.1–16.0 | 24.0–48.0 |
| X | 400–800 | 32.1–64.0 | 16.1–32.0 | >48 |
