Effects of Reclaimed Asphalt Pavement Contents on Construction Characteristics of Asphalt Mixtures

The objective of this research is to explore the influence of high reclaimed asphalt pavement (RAP) content on the construction temperature. Five mixtures with asphalt contents of 2.8%, 3.3%, 3.8%, 4.3%, and 4.8% and RAP content of 20%, 35%, and 50% were analyzed. The optimal asphalt content (OAC) increases with the increasing RAP content, while the added asphalt content decreases. The discharge temperature has a negative correlation with the RAP content. The higher RAP contents and initial water content result in the decrease of paving temperature. Simulated temperature segregation tests show that lower RAP content has little influence on the temperature segregation. Results in the study indicate that RAP could be successfully used in recycled asphalt mixtures depending on the OAC, thermal insulation measures, and suitable climatic conditions.