Ground engineering · Ground improvement
Dynamic compaction: depth of improvement calculator
Depth of improvement, applied energy per unit area and print spacing check.
Standard: Ménard / Lukas (FHWA) D = n√(WH)
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Inputs in the worked example
The live calculator starts with these values; change any of them and every result, check and diagram updates instantly.
| Input | Value | Unit |
|---|---|---|
| Tamper mass | 15 | t |
| Drop height | 20 | m |
| Empirical n (0.3–0.8) | 0.5 | |
| Drops per print | 10 | |
| Print spacing | 5 | m |
| Target depth | 7 | m |
Worked example — results
| Result | Value | Unit |
|---|---|---|
| D = n√(W H) | 8.66 | m |
| Energy per drop | 2,943 | kJ |
| Applied energy per m² (one pass) | 1,177 | kJ/m² |
- ✓ Depth reaches target
Method, formulas and assumptions
- D = n√(W H) = 0.5*SQRT(15*20) = 8.6603 m
- Energy per drop = 15*9.81*20 = 2943 kJ
- Applied energy per m² (one pass) = 10*2943/5^2 = 1177.2 kJ/m²
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For preliminary design and education. Check every result against the current standard and your own engineering judgement before use.