Stabilized emulsions to produce warm asphalt mixtures with reclaimed asphalt pavements

Abstract Stabilized Emulsions (SE) is a Warm Mix Asphalt (WMA) technique that reduces mixing temperatures to approximately 100 °C, the range of WMA with the greatest reduction in temperature compared to Hot Mix Asphalt (HMA). The term ‘stabilized’ refers to the good storage stability of the stabilized emulsion compared to that of common emulsions. Another technique that reduces the environmental impact of asphalt mixtures is the addition of reclaimed asphalt pavement (RAP). This paper presents the research results in which the performance of SE-WMA with different amounts of added RAP were evaluated. SE-WMA was produced at 100 °C, and could be prepared with high RAP contents, reducing the consumption of virgin materials and lowering energy needs. The laboratory study and a pavement trial section were used to evaluate the performance of SE-WMA in comparison with HMA. The experimental results indicated that the physical and mechanical properties of SE-WMA, without RAP, are similar to conventional HMA, showing that the effect of reducing mixing temperature does not significantly affect the quality or performance of these asphalt mixtures. The performance of SE-WMA with 25% and 44% RAP, was slightly lower than that obtained from conventional HMA. However, the quality of the SE-WMA complied with the requirements of conventional HMA, indicating that SSE-WMA with up to 44% RAP content is suitable for pavement construction. Deflections measured in the HMA and SE-WMA trial sections without RAP and with 25% RAP showed similar results, although the SE-WMA with 44% RAP showed 8% higher deflection. The energy consumption to produce one ton of asphalt mixture calculated using a thermodynamic model showed that SE-WMA is effective for the reduction of energy consumption in asphalt plants. Overall, the study concludes that SE-WMA with RAP is a sustainable material for pavement construction that could save energy and consume less virgin material than conventional HMA pavements.

[1]  John T Harvey,et al.  FATIGUE PERFORMANCE OF ASPHALT CONCRETE MIXES AND ITS RELATIONSHIP TO ASPHALT CONCRETE PAVEMENT PERFORMANCE IN CALIFORNIA , 1995 .

[2]  Peter Domone,et al.  Construction materials : their nature and behaviour , 2001 .

[3]  Misko Cubrinovski,et al.  Full-Scale Experiment on Foam Bitumen Pavements in an Accelerated Testing Facility , 2009 .

[4]  John T Harvey,et al.  The effects of asphalt binder and granular material characteristics on foamed asphalt mix strength , 2011 .

[5]  Susan L. Tighe,et al.  Improving the Selection of Virgin Binders for Recycled Hot Mixtures in Ontario , 2015 .

[6]  Baoshan Huang,et al.  Laboratory evaluation of moisture susceptibility of foamed warm mix asphalt containing high percentages of RAP , 2012 .

[7]  Rajib B. Mallick,et al.  Effects of Warm-Mix Asphalt Additives on Workability and Mechanical Properties of Reclaimed Asphalt Pavement Material , 2009 .

[8]  Zhanping You,et al.  The determination of mechanical performance of laboratory produced hot mix asphalt mixtures using controlled RAP and virgin aggregate size fractions , 2012 .

[9]  Kent R Hansen,et al.  Asphalt Pavement Industry Survey on Recycled Materials and Warm-Mix Asphalt Usage: 2014 , 2015 .

[10]  Fujie Zhou,et al.  Impact of recycled asphalt pavement material variability on pavement performance , 2014 .

[11]  Ana Almeida-Costa,et al.  Economic and environmental impact study of warm mix asphalt compared to hot mix asphalt , 2016 .

[13]  Xiao Yao-hu,et al.  On Warm Mix Asphalt , 2010 .

[14]  Arianna Stimilli,et al.  Warm recycling of flexible pavements: Effectiveness of Warm Mix Asphalt additives on modified bitumen and mixture performance , 2017 .

[15]  Xiang Shu,et al.  Laboratory Investigation of Cracking Resistance of Hot-Mix Asphalt Field Mixtures Containing Screened Reclaimed Asphalt Pavement , 2011 .

[16]  Wing-gun Wong,et al.  Effects of moisture on strength and permanent deformation of foamed asphalt mix incorporating RAP materials , 2008 .

[17]  Sheng Zhao,et al.  Comparative evaluation of warm mix asphalt containing high percentages of reclaimed asphalt pavement , 2013 .

[18]  Taleb Al-Rousan,et al.  Performance of Asphalt Mixes Containing RAP , 2008 .

[19]  Kim Jenkins,et al.  Mix design of bitumen-stabilised materials – South Africa and abroad , 2017 .

[20]  Robert L. Lytton,et al.  Evaluation of the Moisture Susceptibility of WMA Technologies , 2014 .

[21]  Rajib B. Mallick,et al.  Pavement engineering : principles and practice , 2008 .

[22]  Pramod Kumar Jain,et al.  Characterization of Reclaimed Asphalt Pavement (RAP) for Use in Bituminous Road Construction , 2013 .

[23]  E. Schlangen,et al.  Effect of RAP and fibers addition on asphalt mixtures with self-healing properties gained by microwave radiation heating , 2018 .

[25]  Erik Schlangen,et al.  Effect of fibres addition on the physical and mechanical properties of asphalt mixtures with crack-healing purposes by microwave radiation , 2016 .

[27]  L. Poulikakos,et al.  Measuring the binder film residues on black rock in mixtures with high amounts of reclaimed asphalt , 2017 .

[28]  Audrey Copeland,et al.  Reclaimed Asphalt Pavement in Asphalt Mixtures: State of the Practice , 2011 .