Design and evaluation of hot asphalt mixtures using 30% and 40% reclaimed asphalt pavement (RAP) contributions

Abstract

Demolition of deteriorated pavements generates large volumes of waste that contaminate the environment. The use of Reclaimed Asphalt Pavement (RAP) in the production of Hot Asphalt Mixtures (HMA) presents a sustainable alternative that turns waste into an integral component of new pavements. The objective of the research is to analyze the properties of dense HMA mixtures incorporating RAP with 30% and 40% contributions in order to identify the benefits that its production can offer. Using the control mix from a predecessor study as a comparative base, the research aims to identify the influence that RAP contributions will have on the stability and flow of the HMA through the Marshall method and on the tensile strength in relation to the change in moisture resistance. For the HMA with a 30% RAP contribution, an optimal asphalt content of 5.3%, a Marshall stability of 3564lbs, a flow of 11.64/100”, and a tensile strength ratio of 82.6% were determined. For the HMA with a 40% RAP contribution, an optimal asphalt content of 5.23%, a Marshall stability of 3502lbs, a flow of 10.97/100”, and a tensile strength ratio of 80.4% were determined. It is concluded that with the increase of RAP, the optimal asphalt content decreases and the susceptibility to moisture damage increases. All determined results are within the standards, so the use of RAP represents a good alternative to HMA made with 100% virgin aggregates.