Site investigation · Laboratory: rock & aggregates
Flakiness index calculator
Flakiness index from the flaky mass in each size fraction.
Standard: AS 1141.15 · BS 812-105.1
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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 |
|---|---|---|
| Fractions: size (mm), mass (g), flaky (g) | 26.5, 820, 96 19, 1140, 171 13.2, 760, 152 9.5, 410, 94 | |
| Specification limit | 25 | % |
Worked example — results
| Result | Value | Unit |
|---|---|---|
| Flakiness index | 16.39 | % |
- ✓ FI ≤ limit
Method, formulas and assumptions
- Flakiness index = 100*SUM([t.mf])/SUM([t.m]) = 16.39 %
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For preliminary design and education. Check every result against the current standard and your own engineering judgement before use.