A comprehensive review on the utilization of reclaimed asphalt material with warm mix asphalt technology

Abstract

Use of reclaimed asphalt pavement (RAP) materials in warm mix asphalt (WMA) mixtures is getting popular around the world due to economic and environmental benefits. However, the performance of WMA containing RAP is one of the main concerns for researchers over the past decade. Many discrepancies can be seen in the literature regarding performance parameters of WMA containing RAP. The main reasons for such vague and contradictory conclusions are the availability of numerous warm mix asphalt technologies, inconsistency in RAP materials, use of various percentages of RAP, adhering to different testing methods to evaluate the performance and the generalization of WMA as a sole technology. Hence, it is important to evaluate and analyze the available literature to understand the performance of RAP in WMA mixture in a holistic approach while focusing on the performance of different technologies separately. This paper extensively evaluates the literature available on the WMA technology, RAP mixtures and finally the incorporation of RAP in WMA to fully understand the performance aspects. From the analysis, it is concluded that the use of RAP in WMA technology can enhance the properties of asphalt mixtures in terms of rutting resistance, moisture susceptibility, and workability. The fatigue performance of WMA mixtures with organic additives are improved whereas both foaming technology and chemical additives show a reduction in fatigue resistance. Even though the analysis shows positive results on low-temperature performance it is recommended investigating more to increase the accuracy of the results.