Superpave evaluation of higher RAP contents using WMA technologies

Abstract In this study, the objective was to conduct an investigation of Superpave mix design characteristics of WMA technologies in terms of various high percentages of reclaimed asphalt pavements (RAPs). One PG 58-28 binder, two PG 64-22 binders, and two RAP sources were selected from South Carolina. In addition, three mix technologies (e.g. hot mix asphalt (HMA), foaming technology, and Evotherm additive) were employed to produce the mixtures. Meanwhile, four RAP contents of 20%, 30%, 40%, and 50% (by weight of total mixture) were utilized to blend with virgin materials. 36 Superpave mix designs were conducted to explore the volumetric characteristics of various mixtures. In this study, the results indicated that, all mixtures have an optimum asphalt content (OAC) less than 5.0%, and most of these values are close to a minimum OAC value of 4.5% set by South Carolina Department of Transportation (SCDOT). No noticeable increases at the mixing and compaction temperatures for these mixtures containing a higher percentage of RAP (i.e., over 40%) were found in this study. In addition, the voids in mineral aggregate (VMA), voids filled with asphalt (VFA), dust/asphalt ratios, and moisture susceptibility meet the requirements of SCDOT’s specifications. Therefore, these specific mix designs could be used as the guidelines for developing a set of specifications for a higher percentage of RAP in terms of warm mix asphalt technology.

[1]  Bradley J. Putman,et al.  Effect of compaction temperature on rutting and moisture resistance of foamed warm-mix-asphalt mixtures , 2013 .

[2]  Rajib B. Mallick,et al.  Evaluation of Heated Reclaimed Asphalt Pavement Material and Wax-Modified Asphalt for Use in Recycled Hot-Mix Asphalt , 2007 .

[3]  Baoshan Huang,et al.  Laboratory Investigation of Mixing Hot-Mix Asphalt with Reclaimed Asphalt Pavement , 2005 .

[4]  B Middleton,et al.  Evaluation of Warm-Mix Asphalt Produced with the Double Barrel Green Process , 2008 .

[5]  Imad L. Al-Qadi,et al.  Mechanical Property Characterization of Warm-Mix Asphalt Prepared with Chemical Additives , 2014 .

[6]  Sheng Zhao,et al.  Laboratory Performance Evaluation of Warm-Mix Asphalt Containing High Percentages of Reclaimed Asphalt Pavement , 2012 .

[7]  Rajib B. Mallick,et al.  Using Warm-Mix Asphalt Technology to Incorporate High Percentage of Reclaimed Asphalt Pavement Material in Asphalt Mixtures , 2008 .

[8]  Wayne Hodo Field and Laboratory Investigation of Foamed Asphalt (Warm-Mix Asphalt) with High Recycled Asphalt Pavement Content for Sustainment and Rehabilitation of Asphalt Pavement , 2009 .

[9]  Wenbin Zhao,et al.  Influence of Antistripping Additives on Moisture Susceptibility of Warm Mix Asphalt Mixtures , 2010 .

[10]  Serji N. Amirkhanian,et al.  Laboratory Investigation of Moisture Damage in Warm-Mix Asphalt Containing Moist Aggregate , 2009 .

[11]  Serji N. Amirkhanian,et al.  Improved Resistance of Long-Term Aged Warm-Mix Asphalt to Moisture Damage Containing Moist Aggregates , 2013 .

[12]  Adam J. T. Hand,et al.  Laboratory and Field Evaluations of Foamed Warm-Mix Asphalt Projects , 2009 .