Influence of warm-mix asphalt technology and rejuvenator on performance of asphalt mixtures containing 50% reclaimed asphalt pavement

Warm-mix asphalt (WMA) technology and rejuvenator are widely used nowadays because of numerous environmental and economic benefits. This study evaluated the effects of warm-mix asphalt (WMA) technology and rejuvenator on the rutting resistance, cracking resistance, and moisture susceptibility of three types of asphalt mixtures. The three types of asphalt mixtures were (a) an asphalt mixture with 50% reclaimed asphalt pavement (RAP), (b) an asphalt mixture with 50% RAP and rejuvenator, (c) a warm mixture containing 50% RAP. The WMA mixtures were plant-produced with a foaming technology commonly used in the United States. Laboratory performance tests included the Superpave indirect tension (IDT) test, tensile strength ratio (TSR) test, asphalt pavement analyzer (APA) rutting test, Hamburg Wheel-tracking test (HWT) and semi-circular bending (SCB) test. Research shows that the rejuvenator could improve the moisture and cracking resistance, but increase the rutting potentials and decrease the indirect tensile strength. In contrast with the mixture with 50% RAP, WMA technology showed promising results in the rutting resistance and moisture susceptibility. Besides, adoption of WMA technology was more cost-effective.