How Mixture, Fabrication, and Plant Production Parameters Affect Mixture Properties

This paper presents summary results from three recently completed projects in the northeast United States to illustrate potential impacts from various mixture, fabrication, and plant production parameters on measured asphalt mixture properties. Binders were evaluated using performance grading, rheological indices, and the Glover-Rowe (G-R) parameter. Mixtures were evaluated with complex modulus, simplified viscoelastic continuum damage (SVECD) fatigue, and pavement life evaluation with layered viscoelastic critical distresses (LVECD). In general, laboratory produced materials were stiffer than plant produced materials and also had lower phase angles. The SVEC fatigue curves change depending on the method as well. The PG of the binder and the amount of recycled material in the mixture impact the magnitude of the differences observed between the laboratory- and plant-produced materials. Reheating material for specimen fabrication changes the measured properties as the materials undergo additional aging during the reheating. The magnitude of the differences depended on the aging susceptibility of the materials. Generally, softer binder grades showed larger differences and the differences were smaller with higher recycle content. As mixtures are kept at elevated temperatures, additional aging may occur that results in stiffening and embrittlement of the materials. Both virgin and reclaimed asphalt pavement (RAP) mixtures experienced changes as a result of being stored in the silo, but the RAP mixture may have experienced larger changes. This indicates that there may be a combination of short-term aging within the silo and a blending or diffusion process occurring with the RAP mixture. These studies have shown that current laboratory protocols do not always capture what happens in the plant and have highlighted the need to recognize potential impacts of fabrication methods and production parameters on measured properties. Additional work needs to be done to determine how the differences in measured properties translate to differences in actual field performance so that appropriate methodologies can be selected and adopted for use in performance-related specifications.

Language

  • English

Media Info

  • Media Type: Digital/other
  • Features: Figures; References;
  • Pagination: pp 1-20
  • Monograph Title: Relationships of Laboratory Mixture Aging to Asphalt Mixture Performance
  • Serial:

Subject/Index Terms

Filing Info

  • Accession Number: 01684115
  • Record Type: Publication
  • Files: TRIS, TRB, ATRI
  • Created Date: Oct 22 2018 1:49PM