Performance evaluation of rutting and moisture damage containing warm mix asphalt mixtures with recycled asphalt pavement

Abstract

Comprehensive road networks are a basis for the economic development of any country. The use of reclaimed asphalt pavement (RAP) serves a distinct part in achieving the national goal of prosperity. This research work presents an experimental study to evaluate the effect of different percentages of RAP on the volumetric properties of asphalt mixtures. Mix designs of one aggregate source and a RAP source with and without the addition of 2% Sasobit for warm mix asphalt (WMA) using 12.5 mm nominal maximum aggregate size were prepared. The mix designs included a control mix with 0% RAP and six samples of HMAs with 10%, 20%, 30%, 45%, 60% and 100% RAP to get an optimal percentage on which performance testing to be done after finding out the volumetric of RAP containing mixtures. This research-study undertakes the rutting susceptibility and moisture damage in RAP incorporated asphalt mixes using the Hamburg Wheel Tracking Device (HWTD). Rutting resistance of only RAP containing mixture is increased up to 18.18% for 20% RAP and RAP containing WMA increased up to 29.12 % for 20% RAP with 2% Sasobit, as compared to the controlled mixtures. Moisture damage results at 50°C temperature of water showed 21.55% increased resistance for 20% RAP and 16.54 % for a mix containing 20% RAP with 2% Sasobit, in comparison to the controlled mixtures. This research showed that all tested HMAs with RAP and WMAs with both RAP and Sasobit performed better than the mixtures prepared with virgin aggregate.