Pavements & traffic · Pavement materials
Asphalt volumetrics (Marshall) calculator
Air voids, VMA and VFA from bulk and maximum densities, with Marshall stability and flow checks.
Standard: AS/NZS 2891 series · AS 2150 · Asphalt Institute MS-2
Open the live calculator → All pavements & traffic calculators
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 |
|---|---|---|
| Bulk density of compacted mix | 2.365 | t/m³ |
| Maximum density | 2.462 | t/m³ |
| Aggregate bulk particle density | 2.64 | t/m³ |
| Binder content (by mix) | 5.2 | % |
| Marshall stability | 10.8 | kN |
| Flow | 3.1 | mm |
| Air voids target min | 3 | % |
| Air voids target max | 5 | % |
| Min VMA | 14 | % |
Worked example — results
| Result | Value | Unit |
|---|---|---|
| Air voids | 3.94 | % |
| VMA | 15.07 | % |
| VFA | 73.86 | % |
| Stability / flow (quotient) | 3.48 | kN/mm |
- ✓ Air voids within target
- ✓ VMA ≥ min
- ✓ Stability ≥ 8 kN
Method, formulas and assumptions
- Air voids = 100*(2.462-2.365)/2.462 = 3.9399 %
- VMA = 100-2.365*(100-5.2)/2.64 = 15.075 %
- VFA = 100*(15.075-3.9399)/15.075 = 73.865 %
- Stability / flow (quotient) = 10.8/3.1 = 3.4839 kN/mm
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For preliminary design and education. Check every result against the current standard and your own engineering judgement before use.