Evaluation of Warm-Mix Asphalt Mixtures Containing Recycled Asphalt Pavement in Nevada

Abstract

This report presents the results of a research study funded by the Nevada Department of Transportation (NDOT) to evaluate the performance of HMA and WMA mixtures containing 0 and 15% RAP binder ratio. Four WMA technologies were evaluated: zeolite foaming process, chemical process, organic (wax) process, and water injection system process. Each mixture was evaluated in terms of its resistance to moisture damage, rutting, and reflective cracking. Asphalt mixtures from four aggregate sources were evaluated; Lone Mountain and North Tenaya from southern Nevada and Spanish Springs and Lockwood from northern Nevada. Based on the analyses of the data generated from this laboratory experiment, the following recommendations can be made: ? NDOT should consider the inclusion of 15% RAP binder ratio with southern mixtures without changing the PG76-22NV grade of the virgin binder. ? NDOT should consider the use of Advera and Evotherm WMA additives in southern mixtures with 0 and 15% RAP binder ratio. ? NDOT should consider the use of the SonneWarmix WMA additive in southern mixtures with 15% RAP binder ratio. ? NDOT may consider reducing the OBC of WMA mixtures by 0.2% for new construction and overlays over un-cracked pavements but must be very cautious with overlays over cracked pavements due to their susceptibility to reflective cracking.