Performance Grade Bitumen (PG Bitumen) is an advanced asphalt binder classified based on its actual performance at specific pavement temperatures rather than traditional empirical tests such as penetration or viscosity. The PG grading system was developed under the Superpave (SUperior PERforming Asphalt PAVEments) program by AASHTO to ensure long-term pavement durability under real traffic loads and climatic conditions.
PG bitumen is engineered to resist rutting at high temperatures, fatigue cracking under repeated traffic loading, and thermal cracking at low temperatures.
Understanding the PG Grading System
PG grades are expressed in the format PG XX-YY:
XX → Maximum average 7-day pavement temperature (°C) the binder can withstand without rutting
YY → Minimum pavement temperature (°C) the binder can endure without thermal cracking
Example: PG 64-22
✔ Reliable performance at +64°C high pavement temperature
✔ Flexible behavior down to −22°C low pavement temperature
Why Performance Grading Is Superior
Reflects actual pavement temperature conditions rather than laboratory assumptions, accounts for climate and traffic loading, minimizes premature pavement failures, and allows precise binder selection for each project location.
Manufacturing & Modification Process
Base Bitumen Selection
Carefully selected refinery residues with stable rheological properties.
Polymer Modification (Optional)
SBS, EVA, or elastomeric polymers enhance elastic recovery, stiffness at high temperatures, and fatigue life.
Rheological Engineering
Binder is engineered for rutting resistance, fatigue resistance, and low-temperature cracking resistance.
Superpave Testing & Certification
Verified using DSR, BBR, RTFO, and PAV aging simulations.
Key Performance Characteristics
✔ Superior temperature resistance
✔ Excellent rutting and fatigue resistance
✔ Enhanced elasticity and flexibility
✔ Strong moisture and adhesion performance
✔ Consistent and predictable quality
Typical Mechanical & Performance Properties
| Property | Typical Range |
|---|---|
| Penetration @25°C | 40 – 90 dmm |
| Softening Point | 55°C – 80°C |
| Flash Point | > 230°C |
| DSR Rutting Parameter (G*/sinδ) | High (Grade Specific) |
| BBR Low Temperature Stiffness | Grade Compliant |
| Elastic Recovery (Modified) | > 70% |
Common PG Grades & Typical Usage
| PG Grade | Typical Application |
|---|---|
| PG 58-22 | Mild climate roads |
| PG 64-22 | Standard highways |
| PG 70-22 | Hot climates, heavy traffic |
| PG 76-22 | Expressways, airports |
| PG 82-22 | Ultra-heavy load pavements |
| PG 64-28 / PG 58-34 | Cold climate regions |
Available Supply Forms
Bulk tanker supply for highway projects, steel drums (180–200 kg), poly bags or jumbo bags for export logistics, and polymer-modified PG bitumen for premium infrastructure.
Applications of Performance Grade Bitumen
Highways and expressways, airport runways and taxiways, urban roads and bus lanes, bridges and flyovers, industrial pavements, container terminals, and roads in extreme climatic regions.
Advantages of PG Bitumen Over VG & Penetration Grades
Climate-specific binder selection, superior durability, lower lifecycle cost, reduced maintenance, and international acceptance as a performance-based standard.