Site investigation · Laboratory: soil classification
Moisture, density & phase relations calculator
Bulk and dry density, void ratio, porosity, saturation and field density ratio, with a three-phase diagram.
Standard: AS 1289.2.1.1 · 5.3.1 sand replacement · 5.8.1 nuclear
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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 |
|---|---|---|
| Wet mass of soil | 2150 | g |
| Volume of hole / mould | 1080 | cm³ |
| Moisture content | 13.5 | % |
| Gs | 2.68 | |
| Lab MDD | 1.86 | t/m³ |
Worked example — results
| Result | Value | Unit |
|---|---|---|
| Bulk density ρ | 1.991 | t/m³ |
| Dry density ρd | 1.754 | t/m³ |
| Unit weight γ / γd | 19.5 / 17.2 | kN/m³ |
| Void ratio e | 0.528 | |
| Porosity n | 34.6 | % |
| Degree of saturation S | 69 | % |
| Saturated density | 2.099 | t/m³ |
| Density ratio ρd / MDD | 94.3 | % |
- ✓ S ≤ 100 % (inputs consistent)
- ✗ Density ratio ≥ 98 % (typical spec)
Method, formulas and assumptions
- ρ = m/V; ρd = ρ/(1 + w)
- e = Gs·ρw/ρd − 1; n = e/(1 + e)
- S = w·Gs/e
- Density ratio = ρd/MDD
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For preliminary design and education. Check every result against the current standard and your own engineering judgement before use.