Review on the fatigue properties of recycled asphalt concrete containing construction and demolition wastes

Road construction is the primary method for high-value utilization of construction and demolition wastes (CDWs), but the research on its application to the asphalt pavement surface layer is still in the early stages of development. The service life of recycled asphalt concrete (RAC) has become a "troublesome issue," so in-depth research on the fatigue properties of RAC is needed. This paper gives a detailed review of the fatigue properties of RAC. First, the properties of recycled aggregates (RAs) are summarized, noting that the properties of RAs and natural aggregates (NAs) vary widely. Recycled concrete coarse aggregates (RCCAs) are most appropriate for the application. Second, the design points of RAC are discussed, and it is concluded that in the design process of RAC, gradation correction is needed. The optimal asphalt content should be calculated by volume index. Third, the fatigue properties test plan and the influence of RAs on it are analyzed, finding that it ignores the applicability of different test methods and the impacts of regional temperature and climate conditions. The existing research mainly focuses on the correlation between recycled aggregate (RA) content and fatigue properties. There is insufficient research on the influence of RA properties on fatigue properties. Finally, future research directions and recommendations for a test plan regarding the fatigue properties of RAC are proposed. Research should focus on the effect of RA properties on fatigue properties. It should be carried out with reasonable test methods, service life characterization models, and climate identical test conditions to clarify the durability index. The evaluation system of fatigue properties of RAC should be established, and solid theoretical supports for the application of CDWs should be provided, thereby accelerating the application of recycled asphalt pavement containing CDWs.