A series of material parameters and production process parameters need to be determined in the design of hot in-plant recycled asphalt mixture, so as to make the pavement performance of recycled asphalt mixture meet the specification requirements. The rational determination of the aggregate gradation of the recycled mixture and the performance of the recycling agent, as critical parameters of the recycling design, has an important impact on the pavement performance of the recycled asphalt mixture. In this study, reclaimed asphalt pavement (RAP) from a seriously damaged pavement in Dalian, China was collected for recycling. Four recycling approaches with two different gradations and two different methods of recycling agent addition were designed, and the best recycling scheme was determined by a range of pavement performance tests. The results show that for the same method of adding recycling agent, the recycled asphalt mixture with the gradation close to the mid-value had better pavement performance, especially moisture damage resistance. Also, the two methods of adding recycling agent with different mechanisms exhibited basically the same performance of the recycled asphalt mixtures.
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