Moisture Susceptibility and Rut Resistance of RAP Asphalt Mixtures with High Percentage of Natural Sand

Abstract

The objective of this research study was to conduct a laboratory investigation of reclaimed asphalt pavement (RAP), containing a high percentage of natural sand mixtures, in terms of moisture susceptibility, permanent deformation, and fracture energy with respect to the use of both hydrated lime and liquid antistripping additives (ASAs). The experimental design included one base binder, one natural sand, three ASAs, two aggregate sources, two RAP contents, and two surface mix types (Types B and C). A total of 12 mixtures were investigated and a total of 160 specimens were made and tested in this study. The test results indicated that the indirect tensile strength (ITS) and tensile strength ratio values of RAP with 20% natural sand showed that hydrated lime and liquid ASAs could be used to resist moisture damage, regardless of the aggregate source. In addition, the rut depths of Surface C mixtures were generally less than 5 mm, irrespective of aggregate source and ASA type. Moreover, various ASAs, aggregate sources, and surface types slightly affect the dissipated energy of wet samples. Furthermore, there are some general correlations between dissipated energy and its corresponded ITS values, in terms of aggregate source and surface type used in this study.