Description
Pre-treated crumb rubber technologies are emerging based on the idea of making asphalt rubber mix production more efficient in the field. The objective of this research study was to evaluate the rheological and aging properties of binders modified with one such product. Two binders were used for this study: Performance Grade PG 70-10 and PG 64-22. Laboratory tests included: penetration, softening point, viscosity, Dynamic Shear Rheometer (DSR) and Bending Beam Rheometer (BBR). Tests were conducted using original, short-term aging conditions, and long-term aging conditions. Observations from the results indicate that there was a higher improvement when the activated binder was added to the softer, PG 64-22 binder. For short-term aging, the modified binder showed a higher aging index compared to the control. However, long-term aging was more favorable for the modified binders. The DSR results showed that the PG 64-22 binder high temperature would increase to 82°C, and PG 70-10 would be increased to 76°C, both favorable results. The intermediate temperatures also showed an improvement in fatigue resistance. Test results at low temperatures were also favorable and showed reduced stiffness.
