Bitumen Performance Grade 70-16
High-Temperature Performance:
The PG 70-16 bitumen exhibits excellent high-temperature performance, suitable for pavements experiencing maximum pavement design temperatures below 70 °C. Its Dynamic Shear Rheometer (G/sinδ)* value at 70 °C reaches the minimum required 1 KPa, ensuring strong resistance against rutting. After Rolling Thin Film Oven (RTFO) aging, the G*/sinδ remains at 2.2 KPa at 70 °C, confirming continued stability under short-term aging. The bitumen also maintains a flash point above 230 °C and a viscosity of 3 Pa.s at 135 °C, facilitating safe handling and effective mixing during asphalt production. These characteristics make PG 70-16 ideal for high-traffic roads in hot climates.
Low-Temperature Performance and Long-Term Durability:
At low temperatures, PG 70-16 ensures pavement flexibility and crack resistance. The Bending Beam Rheometer (PAV) and creep stiffness results indicate a maximum stiffness of 300 MPa and a minimum m-value of 0.300 at -6 °C, demonstrating excellent resistance to thermal cracking. Additionally, the direct tension failure strain at -6 °C exceeds 1 %, and the critical low cracking temperature determined by PP42 is also -6 °C, highlighting its suitability for cold-weather conditions. The bitumen maintains long-term durability with a maximum G*/sinδ of 5000 KPa after PAV aging, providing a balanced combination of flexibility at low temperatures and rutting resistance at high temperatures for highways and heavy-duty pavements.
| Bitumen PG 70-16 Specification | |||
|---|---|---|---|
| Specification | Unit | Value | Method |
| Average 7-Day Maximum Pavement Design Temperature | °C | < 70 | – |
| Minimum Pavement Design Temperature | °C | > -16 | – |
| Flash Point Temperature | °C | Min 230 | AASHTO T48 |
| Viscosity Maximum 3 Pa.s, Test Temperature | °C | 135 | AASHTO T316 |
| Dynamic Shear G*/sin Minimum 1 KPa Test Temperature | °C | 70 | AASHTO T315 |
| Rolling Thin Film Oven Test (AASHTO T240) | |||
| Mass Change | % | Max 1.00 | – |
| Dynamic Shear G*/sin Minimum 2.2 KPa Test Temperature, @10 rad/s | °C | 70 | AASHTO T315 |
| Pressure Aging Vessel (PAV) Test (AASHTO R28) | |||
| PAV Aging Temperature | °C | 100 (110) | AASHTO R28 |
| Dynamic Shear G*/sin Maximum 5000 KPa Test Temperature, @10 rad/s | °C | 31 | AASHTO T315 |
| Creep Stiffiness S Maximum 300 Mpa M-Value Minimum 0.300 Test Temp,@60s | °C | -6 | AASHTO T313 |
| Direct Tension Failure Strain Minimum 1 % Test Temp@1mm/min | °C | -6 | AASHTO T314 |
| Critical Low Cracking Temperature Critical Cracking Determined by PP42 Test Temp | – | -6 | AASHTO PP42 |
