Effects of Filler Types and High RAP Content on the Ability of HMA to Withstand Moisture Damage

Civil Engineering Department, University of Technology, Baghdad, Iraq

^a* Corresponding author bce.20.23@grad.uotechnology.edu.iq
^b 40273@uotechnology.edu.iq
^c 40162@uotechnology.edu.iq

Abstract

Using hot mix asphalt (HMA) and recycled asphalt pavement (RAP) simultaneously has many technological benefits. At all service temperatures, moisture damage is a hazard with these mixes. Thus, moisture's effects on mixtures' effectiveness were studied using experimental techniques, such as the tensile strength ratio (TSR). Four different ratios of RAP for the surface layer (20, 30, 40, and 50%)) were added to the asphalt mixture (HMA) to study as well as find the content Optimal RAP for both layers RAP through Marshall stability and hygroscopic resistance of asphalt mixtures through moisture damage is examined. The ratio (TSR) of the optimal RAP content mixture is compared with the asphalt mixture without RAP for three fillers and for both layers. The findings revealed a slight reduction in tensile strength of the (HMA) that does not contain RAP in contrast to the asphalt control mix containing the reclaimed pavement, where it was found that the percentages were slightly more and still higher than 80%. The results indicate that, in general, "Hot asphalt mixtures" containing RAP can be recommended for areas that experience moisture damage without worrying about environmental and natural resource restrictions.