Abstract:In order to investigate the influence of gradation, RAP content and compaction temperature on the compaction characteristics of RHMA, such as void ratio(VV), compaction energy index(CEI), slope of accumulated compaction energy(K) and lock point. The orthogonal experiment was designed, and the influence degree between the factors and the compaction characteristic index were analyzed by range and variance analysis, and variation law was analyzed by regression model. In addition, the influence of different factors on compaction characteristics is further demonstrated by field construction. The results show that gradation, RAP content and compaction temperature have significant influence on the compaction characteristics of RHMA, and the influence degree of gradation is higher than that of RAP content. The relationship between the factors and the compaction characteristic indexes of VV and CEI were established by quadratic regression model, and the VV and CEI are negatively correlated with the changes of gradation, RAP content and compaction temperature. The proposed results was proved valid in project of the Sanming section of Fuzhou-Yinchuan expressway, and the gradation can significantly affect the VV of recycled asphalt mixture, and the finer the gradation, the easier the compaction.