A Synthesis of Asphalt Foaming Parameters and Their Association in Foamed Binder and Mixture Characteristics

Water injected foamed warm mix asphalt (WMA) accounts for about 90% of all WMA produced in the last several years in the United States. This study aims for a documentation of recently developed asphalt foaming parameters and their correlation with foamed binder and mixture characteristics based on existing foamed WMA research. Incorporation of 1–3% water into hot binder stream at 141–171°C results in foamed asphalt binder through binder volume expansion and viscosity reduction, which is intended to improved coatability and workability. Foaming parameters: expansion ratio (ER), half-life (HL), surface area index (SAI), foamability index (FI), and collapse rate of semi-stable bubbles (k-value), together with foamed binder and mixture properties have been synthesized. Foaming water content (FWC) is found as a key parameter of foamed WMA practices. Optimization of FWC and subsequent evaluation of mixture properties show that foamed asphalt mixtures exhibit performance that is equivalent to or better than that of conventional hot mix asphalt (HMA).


  • English

Media Info

  • Media Type: Web
  • Pagination: pp 256-267
  • Monograph Title: Airfield and Highway Pavements 2017: Testing and Characterization of Bound and Unbound Pavement Materials

Subject/Index Terms

Filing Info

  • Accession Number: 01688477
  • Record Type: Publication
  • ISBN: 9780784480939
  • Files: TRIS, ASCE
  • Created Date: Oct 4 2018 4:34PM