Site investigation · Laboratory: soil classification
Organic content (loss on ignition) calculator
Loss on ignition from crucible masses, with the AS 1726 organic description.
Standard: AS 1289.4.1.1 (related) · ASTM D2974
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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 |
|---|---|---|
| Crucible | 32.1 | g |
| Crucible + oven-dry soil | 52.4 | g |
| Crucible + ash | 50.82 | g |
Worked example — results
| Result | Value | Unit |
|---|---|---|
| Loss on ignition | 7.78 | % |
| Description | organic soil |
- ✗ Organic content < 2% (inorganic fill)
Method, formulas and assumptions
- Loss on ignition = 100*(52.4-50.82)/(52.4-32.1) = 7.7833 %
- Description = IF(7.7833<2,"inorganic",IF(7.7833<25,"organic soil","peat")) = organic soil
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For preliminary design and education. Check every result against the current standard and your own engineering judgement before use.