Preliminary examination of soybean oil derived material as a potential rejuvenator through Superpave criteria and asphalt bitumen rheology

The increased use of recycled asphalt materials in bituminous mixtures has led to increasing interest in rejuvenators. Rejuvenators are primarily used to restore the rheological properties of aged bitumens to their unaged state. In this work, the effect of adding a soybean-derived biomaterial at a 0.75% by mass of bitumen to a polymer modified PG64-28 and a neat PG58-28 is studied. Dynamic Shear Rheometer, Bending Beam Rheometer, and Rotational Viscometer are used to characterize the bitumens rheology. The effect of aging on the longevity of the soybean additive is examined. It was revealed that this material is a viable candidate as a rejuvenator. At such low dosage, it had a remarkable effect on the fatigue and low temperature properties of both bitumens. It also led to a notable decrease in the complex shear modulus accompanied by an increase in the phase angle, which is essentially reversing the effect of aging.