To evaluate the effect of rejuvenating agent on reclaimed SBS (styrene-butadiene-styrene) modified asphalt pavement (RSMAP) material, different tests of asphalt and mixtures were conducted. Firstly, the improvement effect of rejuvenating agents on the aged modified asphalt was tested at macroscopic and microscope level. Then the properties of hot mix asphalt (HMA) with different RSMAP contents (0%, 30%, 50% and 70%) were evaluated by conducting freeze-thaw split, semi-circular bending (SCB) and dynamic modulus (DM). The results indicate that rejuvenating agent can recycle the properties of aged modified asphalt effectively. The initial phase structure of the aged modified asphalt is not changed by adding rejuvenating agents. Moreover, the SBS particles area ratio of modified asphalt blends is significantly correlated with tenacity as the proportion of rejuvenating agent increases. For mixtures, RSMAP is harmful to moisture susceptibility and low-temperature cracking resistance of recycled mixture, especially with high RSMAP content. Moreover, the two properties can be improved by adding rejuvenating agents, but the recycled mixtures with high RSMAP content are not easy to recover to HMA mixture level. In general, the rejuvenating agent has an effect on the stiffness of the recycled mixture, but this is effect not obvious. When loading frequency reaches a higher value, the DM of recycled mixtures and HMA mixture tend to be consistent including high RSMAP content.

Increasing the percentage of reclaimed styrene-butadiene-styrene (SBS)–modified asphalt pavement (RAP-SBS) is a promising way to promote the development of sustainable roadway systems. The excellent properties of RAP-SBS are the key to its application in high percentages. This study evaluates the properties of hot mix asphalt (HMA) mixtures with 0%, 30%, 50%, and 70% RAP-SBS replacement in terms of rutting, low-temperature anticracking, and moisture susceptibility. The dynamic modulus test evaluates the stiffness. Both unaged and long-term aged (LOTA) samples are evaluated. Moreover, the effect of freeze-thaw (F-T) cycles on the splitting strength is also investigated. The results show that the RAP-SBS is feasible to recycle, and HMAs mixture with higher percentages of RAP-SBS exhibit better rutting resistance, and lower anti-cracking properties and moisture susceptibility. When the RAP-SBS percentage is less than 30%, the anticracking property of the recycled mixture is basically close to that of HMA mixture between $-20$ to $-10°\mathrm{C}$ , and the moisture susceptibility of the two types of mixture is similar when the percentage is less than 50%, but the durability of both recycled mixtures is poor. In addition, no continuous increase in dynamic modulus is demonstrated as the RAP-SBS percentage increases. When subjected to F-T cycles, the strength of mixtures with RAP-SBS is more sensitive than that of HMA mixtures, especially for mixtures with high RAP-SBS percentages.