Permanent Deformation Characteristics of Hot Recycled Blends of Three Different RAP Sources

yAs the road networks are expanding worldwide, recycling pavements, both flexible and rigid pavements, is an important area of research nowadays. To achieve the sustainability objectives in the road construction industry, extensive research focused on reclaimed asphalt pavement (RAP) is required. Rheological parameters like Superpave stiffness parameter (G*/sin delta), true high PG temperature (PGH), and Zero Shear Viscosity (ZSV) have been widely used to study the permanent deformation characteristics of asphalt binder. The experimental campaign includes three RAP sources (RAP-D, RAP-UP, and RAP-UK) and one Recycling Agent, RA (soft binder grade VG-10). The proportion of RAP binder in total binder was 0%, 15%, 25%, 40%, 65%, 80%, and 100% (RAP binder) by weight of total binder. It was found that for highly aged RAP source having PGH of 154 degrees C, the linear blending chart concept is not applicable. Similarly, the tiered approach of RAP incorporation was found to over-predict the minimum RAP content when the RAP binder is highly aged. For the three RAP sources, it was observed that a log-linear relationship can improvise the conventional log-log relationship between PGH and ZSV. The same was verified with the statistical analysis and using a scatter plot of matrices (SPLOM). The effect of RAP content on mixing and compaction temperature of the hot recycled mix was analyzed based on the equi-viscous approach.