Effect of long-term ageing on properties of RAP inclusive WMA mixes

Abstract

This paper is an attempt to enhance the long-term performance of Reclaimed Asphalt Pavement (RAP) inclusive dense bituminous macadam (DBM) mixes, in post ageing condition, via inclusions of a Warm Mix Additive. Two sources of Reclaimed Asphalt Pavement (RAP) with two inclusion proportions (35% and 70%) were considered. The effect of inclusions of both the technologies (RAP & WMA) on various properties of DBM mixes such as Marshall Stability, retained Marshall Stability, indirect tensile strength (wet & dry), rutting resistance and Cantabro abrasion loss were studied. Inclusions of WMA was found to significantly improve the aforementioned properties of the DBM mixes regardless of the type of aggregate used. Moreover, the RAP-WMA mixes were found to retain much of its properties even after long-term ageing as compared to RAP-HMA mixes. RAP fraction up to 35% may be used for DBM mixes without much compromising the mechanical and durability properties of the same (as found in the present study). Incorporation of WMA in these mixes would further improve the properties and would ensure the longevity even in the worst conditions of moisture. © 2019 Elsevier Ltd