Impact of Coal Combustion Product Incorporation in Asphalt Mixture Performance

According to the American Coal Ash Association (ACAA) 129 million tons of Coal Combustion Product (CCP) are being produced but only 48% is currently being utilized in different applications. The remaining 52% goes to landfills. Moreover, only 0.13% of the CCP used is being used as mineral filler in asphalt cement. The need for better infrastructure together with the fact that very few researchers have reported on the benefits of CCP in asphalt binders and mixtures opens up new opportunities for beneficial CCP applications. The results of this study put significant confidence in CCP utilization in asphaltic mixtures (ASHphalt) in general and pavements in specific, as made evident by the results of the testing program. In this study, the CCP was introduced as part of the asphalt binder rather than the traditional approach of adding fillers as part of the aggregate. When fabricating samples, 10% of the optimum asphalt content is replaced with CCP of different physical and chemical properties. Mixing and compacting of ASHphalt samples showed no change in properties compared to control mix. The laboratory performance results validated the hypothesis that some CCPs can act as enhancers and extenders to the binder. Significant improvement was observed for mixture aging resistance, moisture damage resistance, fatigue life, and thermal cracking resistance. As compared to the control mix, the ASHphalt samples showed an increase in the tensile strength (dry and wet), an increase in the tensile strength ratio, up to 5.5 times increase in fatigue life, and an increase in low temperature fracture energy ranging from 22% to 120%. In summary, this study shows that replacing 10% of the asphalt binder by volume with some CCPs does not hinder workability, and can potentially improve aging resistance, moisture damage resistance, fatigue life, and thermal cracking resistance. This implies significant impact on CCP utilization in flexible pavements rather than sending it to landfills.

• Supplemental Notes:
  • This paper was sponsored by TRB committee AFK30 Standing Committee on Non-Binder Components of Asphalt Mixtures. Alternate title: Impact of Coal Combustion Products Incorporation in Asphalt Mixtures Performance.
• Corporate Authors:

  Transportation Research Board

  500 Fifth Street, NW
  Washington, DC  United States  20001
• Authors:
  • Faheem, Ahmed
  • Cloutier, Clayton
  • Bautista, Emil G
  • Sobolev, Konstantin
• Conference:
  • Transportation Research Board 96th Annual Meeting
  • Location: Washington DC, United States
  • Date: 2017-1-8 to 2017-1-12
• Date: 2017

Language

• English

Media Info

• Media Type: Digital/other
• Features: Figures; Photos; References; Tables;
• Pagination: 17p
• Monograph Title: TRB 96th Annual Meeting Compendium of Papers

Subject/Index Terms

• TRT Terms: Aging (Materials); Asphalt mixtures; Fatigue (Mechanics); Fly ash; Moisture damage; Salvage; Tensile strength; Thermal degradation; Waste products (Materials)
• Uncontrolled Terms: Coal combustion products; Tensile strength ratio
• Subject Areas: Highways; Materials; Pavements;

Filing Info

• Accession Number: 01629816
• Record Type: Publication
• Report/Paper Numbers: 17-05853
• Files: TRIS, TRB, ATRI
• Created Date: Mar 26 2017 5:39PM