Superpave Bitumen Specification
Last updated: 2026-09-30
Superpave bitumen is a performance-graded (PG) asphalt binder specified under AASHTO M 320 / MP1, classified by the maximum and minimum pavement temperatures it must withstand, such as PG 64-22 or PG 70-28. A standard PG 64-22 binder typically costs USD 480–560 per metric ton FOB depending on crude source and region, versus USD 520–610 per ton for polymer-modified PG 76-22. Superpave grading replaced the older penetration and viscosity systems precisely because it ties binder performance directly to climate and traffic loading.
What Is Superpave Bitumen? Definition and Grading System
Superpave (Superior Performing Asphalt Pavements) is a mixture design and binder specification system developed under the U.S. Strategic Highway Research Program (SHRP) between 1987 and 1993, with a budget of approximately USD 150 million. The binder portion, AASHTO M 320, grades bitumen by average seven-day maximum pavement design temperature and minimum pavement design temperature, expressed as PG XX-YY.
The key principle: instead of testing bitumen at arbitrary reference conditions (25°C penetration, 60°C viscosity), Superpave tests it at the temperatures the pavement will actually experience. A PG 64-22 binder means the binder must resist rutting up to 64°C and thermal cracking down to -22°C.
Three critical test parameters define the grade:
- Original binder: Dynamic Shear Rheometer (DSR), G/sin δ ≥ 1.00 kPa at the high-temperature grade
- RTFO-aged (rolling thin film oven): G/sin δ ≥ 2.20 kPa — simulates short-term aging during mixing and paving
- PAV-aged (pressure aging vessel): G·sin δ ≤ 5,000 kPa at intermediate temperature, plus creep stiffness ≤ 300 MPa and m-value ≥ 0.300 at low temperature
| PG Grade | High Temp (°C) | Low Temp (°C) | Typical Climate | Common Use |
|---|---|---|---|---|
| PG 58-28 | 58 | -28 | Cool, moderate traffic | Secondary roads |
| PG 64-22 | 64 | -22 | Most of US, EU temperate | Highways, standard |
| PG 64-28 | 64 | -28 | Cold winters, hot summers | Interstate, heavy load |
| PG 70-22 | 70 | -22 | Hot climate, high traffic | Urban arterials |
| PG 76-22 | 76 | -22 | Extreme heat, slow traffic | Intersections, ports |
| PG 82-22 | 82 | -22 | Desert, standing loads | Airfields, terminals |
Note the 6°C increments in high temperature and 6°C increments in low temperature — this is the standard Superpave grading ladder, so grades cannot be "invented" arbitrarily.
How Superpave Bitumen Differs from Penetration and Viscosity Grades
Superpave grades are climate-specific, while penetration (pen) grades are consistency-specific. This is the single biggest difference buyers need to understand.
A pen 60/70 binder tells you nothing directly about performance at 70°C or -20°C. A PG 64-22 tells you exactly that. For exporters, this means the same base bitumen can be certified to multiple PG grades depending on crude source and additive package.
- Penetration grades (ASTM D946): graded at 25°C, 100 g, 5 s — legacy system, still dominant in Africa, South Asia, Middle East
- Viscosity grades (ASTM D3381): graded at 60°C — legacy US system
- Superpave PG grades (AASHTO M 320): graded across the full service temperature range
| Parameter | Pen 60/70 | PG 64-22 |
|---|---|---|
| Grading basis | Needle penetration at 25°C | Pavement service temperature |
| Rutting resistance | Not directly specified | G/sin δ ≥ 1.00 / 2.20 kPa |
| Thermal cracking | Not directly specified | Creep stiffness ≤ 300 MPa |
| Aging simulation | None built in | RTFO + PAV required |
| Typical price (USD/MT FOB) | 430–500 | 480–560 |
| Main markets | Africa, South Asia | USA, Canada, EU, Australia |
Practical takeaway: If your project is in a region with 40°C+ summer pavement temperatures and slow-moving traffic, pen 60/70 is a gamble. PG 70-22 or PG 76-22 is the engineered answer.
Superpave Bitumen Specifications: AASHTO M 320 Test Requirements
The full AASHTO M 320 specification runs to more than a dozen tests. Below are the commercially decisive ones.
| Test | Standard | Requirement | Purpose |
|---|---|---|---|
| Flash point | AASHTO T 48 | ≥ 230°C | Safety in handling |
| Rotational viscosity @ 135°C | AASHTO T 316 | ≤ 3.0 Pa·s | Pumping/mixing workability |
| DSR G/sin δ @ high temp | AASHTO T 315 | ≥ 1.00 kPa | Rutting resistance (unaged) |
| Mass loss after RTFO | AASHTO T 240 | ≤ 1.00% | Volatile loss control |
| Test | Standard | Requirement | Purpose |
|---|---|---|---|
| DSR G/sin δ (RTFO) | AASHTO T 315 | ≥ 2.20 kPa | Rutting after aging |
| DSR G·sin δ (PAV) | AASHTO T 315 | ≤ 5,000 kPa | Fatigue cracking |
| BBR creep stiffness S (PAV) | AASHTO T 313 | ≤ 300 MPa | Low-temp cracking |
| BBR m-value (PAV) | AASHTO T 313 | ≥ 0.300 | Stress relaxation |
| Direct tension (optional) | AASHTO T 314 | ≥ 1.0% failure strain | Extreme low-temp |
Rotational viscosity at 135°C ≤ 3.0 Pa·s is one of the most frequently failed parameters in imported binder. If your supplier's binder exceeds 3.0 Pa·s at 135°C, the mixing plant will need higher temperatures, driving up fuel cost by roughly 5–8%.
Superpave Bitumen Pricing and Logistics Data
Superpave-grade binders carry a premium over penetration grades because of tighter crude selection and, for PG 70-22 and above, polymer modification (typically 2–4% SBS by weight).
| Grade | USD / Metric Ton | Premium vs Pen 60/70 | Modification |
|---|---|---|---|
| Pen 60/70 (reference) | 430–500 | — | None |
| PG 58-28 | 460–520 | +5–7% | None |
| PG 64-22 | 480–560 | +8–12% | None |
| PG 64-28 | 495–575 | +12–16% | None |
| PG 70-22 | 510–590 | +15–20% | Optional |
| PG 76-22 | 520–610 | +18–25% | SBS 2–4% |
- Standard shipment: 1,000–5,000 MT per vessel parcel
- Flexitank / ISO tank: 20–24 MT per unit
- New steel drum: 150–182 kg net, 110–150 drums per 20 ft container
- Jumbo bag (1 MT): 20 bags per 20 ft container
- Typical lead time: 10–25 days from order confirmation to loading, depending on refinery schedule
- Minimum order quantity (MOQ): usually 100–500 MT for drummed, 1,000 MT+ for bulk vessel
Viscosity and temperature note: Superpave binders must be stored at 150–165°C and mixed at 160–175°C. Every 10°C of unnecessary overheating ages the binder and can push PAV G·sin δ past the 5,000 kPa fatigue limit.
Choosing the Right Superpave Grade for Your Project
Grade selection is driven by three inputs: climate, traffic speed, and traffic volume (ESALs). Superpave's high-temperature grade can be bumped by one or two levels (6°C or 12°C) for slow or standing traffic.
| Condition | Recommended PG | Reason |
|---|---|---|
| 7-day max pavement temp 58°C | PG 58-XX | Base high-temp grade |
| 7-day max pavement temp 64°C | PG 64-XX | Most common globally |
| Slow traffic (< 20 km/h) at 64°C | PG 70-22 | +1 grade for loading |
| Standing traffic (ports, terminals) | PG 76-22 | +2 grades, SBS required |
| Min pavement temp -22°C | -22 low grade | Standard cold grade |
| Min pavement temp -28°C | -28 low grade | Cold climate |
| Min pavement temp -34°C | -34 low grade | Severe cold |
Rule of thumb: Add one 6°C grade step for traffic between 10–20 km/h, and two steps for traffic below 10 km/h or standing loads. This is why PG 76-22 dominates at ports, bus terminals, and heavily congested intersections.
FAQ: Superpave Bitumen
What does PG 64-22 mean in Superpave bitumen?
PG 64-22 means the binder must resist rutting at pavement temperatures up to 64°C and thermal cracking down to -22°C, verified by DSR and BBR testing under AASHTO M 320. The "64" is the average seven-day maximum pavement design temperature, and "-22" is the minimum pavement design temperature.
Is Superpave bitumen better than pen 60/70?
They serve different specification systems, but Superpave grades are performance-based and climate-specific, making them more reliable for rutting and cracking control. Pen 60/70 remains cheaper at USD 430–500 per MT versus USD 480–560 per MT for PG 64-22, so the choice depends on project requirements and local standards.
What is the price difference between PG 64-22 and PG 76-22?
PG 76-22 typically costs USD 520–610 per metric ton FOB, roughly 8–10% more than PG 64-22 at USD 480–560 per MT. The premium comes from SBS polymer modification at 2–4% by weight and tighter crude selection.
How is Superpave binder tested?
Three stages are used: original binder (DSR, viscosity, flash point), RTFO-aged residue (simulates mixing and paving), and PAV-aged residue (simulates 7–10 years of service). Key limits include G/sin δ ≥ 1.00 kPa unaged, ≥ 2.20 kPa after RTFO, and G·sin δ ≤ 5,000 kPa after PAV.
What is the maximum rotational viscosity allowed for Superpave bitumen at 135°C?
AASHTO M 320 requires rotational viscosity at 135°C to be ≤ 3.0 Pa·s for all PG grades. Binders exceeding this limit are harder to pump and mix, and require higher plant temperatures that increase fuel consumption and accelerate binder aging.
Get an Instant Superpave Bitumen Cost Estimate
Pricing on Superpave grades moves with crude benchmarks, polymer costs, and freight rates — often week to week. Before you commit to a 1,000 MT PG 64-22 or PG 76-22 parcel, run the numbers properly.
Use the 6Tar cost calculator to model your landed cost per metric ton, including FOB price, freight, drums or flexitank, insurance, and port charges. It takes under two minutes and gives you a per-ton figure you can take straight into negotiation — so you never overpay on a Superpave binder shipment again.