FATIGUE AND MOISTURE SUSCEPTIBILITY CHARACTERISTICS OF RECLAIMED ASPHALT PAVEMENT MIXTURES IN IRAQ

Abstract

: One of today’s most important societal concepts is sustainability. This ideal can be described as meeting the needs of the present without compromising the ability of future generations to meet their own needs. Hot mix asphalt (HMA) recycling produces an eco-friendly mixture known as Reclaimed Asphalt Pavement (RAP). The main objective of this paper is to determine the effect of RAP percentage usage on the characteristics and properties of asphalt concrete mixtures. In this paper, a detailed laboratory study is carried out by preparing asphalt mixtures specimens using aggregate from Al-Nibaay quarry, (40-50) grade asphalt from dourah refinery and four different percentages of RAP material: 0%, 5%, 10%, and 15%. The experimental testing program included four point repeated load and Indirect Tensile Strength tests. The experimental results indicate that, that the inclusion of RAP materials improves fatigue properties of HMA mixtures; fatigue life (Nf (at RAP content of (15 %) increases by (157.1%), (100%), and (150%) at testing temperature 25, 10, and 40°C respectively. Based on the modified Lottman test, it was found that HMA with RAP additive had a high resistance to moisture damage through increasing the indirect tensile strength of such mixtures. The results of four point repeated load test and IDT test indicate that the amount of new binder that needs to be added to the RAP mixture can be reduced without significant effects on the quality of the produced mix.