Reference Guide & Unit Converter
Asphalt Density
Understanding density parameters for converting compacted asphalt volume to total mass and tonnage.
Asphalt Density Unit Converter
Convert asphalt mix density values between SI metric and imperial units.
kg/m³2,400
t/m³2.40
lb/ft³149.83
What Is Asphalt Density?
Asphalt density represents the mass of a compacted asphalt mixture per unit of volume. It serves as the mathematical bridge connecting geometric field measurements (length, width, thickness) to physical material weight (tonnes or US tons).
Mass (kg) = Volume (m³) × Density (kg/m³)
Typical Asphalt Mix Density Ranges
Density varies based on aggregate specific gravity, bitumen binder content, air void targets, and field compaction effort. Below are standard engineering benchmarks:
| Material State / Mix Type | kg/m³ | t/m³ | lb/ft³ |
|---|---|---|---|
| Standard Compacted HMA (Default Example) | 2400 | 2.40 | 149.8 |
| Stone Mastic Asphalt (SMA) | 2380 – 2460 | 2.38 – 2.46 | 148.5 – 153.5 |
| Loose / Uncompacted Hot Mix | 1600 – 1800 | 1.60 – 1.80 | 99.8 – 112.3 |
| Milled Asphalt (RAP) Bulk Loose | 1400 – 1600 | 1.40 – 1.60 | 87.4 – 99.8 |
Factors Influencing Field Density
- Compaction Roller Operations: Steel-wheel vibratory and pneumatic-tire rollers reduce air voids to target percentages (typically 3%–5%).
- Aggregate Mineralogy: Dense basalt or granite aggregates yield higher mix densities than lighter limestone formulations.
- Temperature Loss: Cool ambient temperatures during placement inhibit proper roller compaction, lowering final density.