Investigation of Compaction Process of Graphene Nano-Platelet Modified Asphalt Mixtures

The project will perform a series experiments and simulations to build a framework for modeling the Graphene Nano-Platelet (GNP) influenced improved compactivity of asphalt mixtures. To do so, the project will consider asphalt mixtures in their most common form, a combination of gravel and other macroscopic particles in a crude oil residue comprised of a viscoelastic matrix with dispersed hard mineral colloidal particles. The work over the course of the year involves three research tasks: Task 1: The project will perform rheological measurements to determine how the properties of the binder change with percentage of GNP added using a temperature-controlled Brookfield rheometer. The results will be compared with previous theoretical predictions and experiments on the behavior of similar but more idealized viscoelastic fluids with particle dispersions. Task 2: The project will perform computational simulations of the compaction process using the measured rheological properties of the binder to help investigate how the GNP influences the compaction behavior of asphalt mixtures, e.g., through binder rheology or effective interparticle friction. The modeling component will primarily be based on an in-house Discrete Element Method (DEM) code where the macroscopic particles are simulated directly and the effect of the GNP on binder rheology and friction coefficients are parameterized. The form of the parameterization will be twofold: (1) a lubrication-like modification of the interparticle forces based on measured viscoelastic binder rheology and (2) the less-well-understood interparticle frictional modification based on measurements of other unbound materials. The influence of the small amount of air in the binder will be incorporated using the mixture theory. The project will set up boundary conditions similar to those run in laboratory compaction tests and field installations so the project can validate and improve the model through comparisons with previously published data and new experiments performed over the year of the project (Task 3). To maximize the generalizability and thus future use of the model for practical applications, the project team will also use the simulations to build an understanding of the physics that governs the influence of the GNP-modified binder on the asphalt compactivitity. These include particle-scale effects such as mesoscopic interparticle force structures (e.g., force chains) and system scale effects such as the evolution of the constitutive behavior. Over the course of the year, the project plan to develop a more fully coupled computational fluid dynamics/discrete element method (CFD/DEM) model, likely based on CFDEM ( an open source parallelizable code for coupled CFD and DEM simulations to enable the development of protocols for use of GNP for improved performance in specific applications, including large-scale field installations. Task 3: The project will perform compaction experiments using binder mixtures measured in Task 1 with particles of similar size distributions simulated in Task 2 to help validate the code. The project will compare measured compaction with those predicted to the simulations to improve the parameterizations in the both generations of the simulations. Compaction curves of asphalt mixtures with (B, C, D) and without (A) addition of GNPs parametric studies, from which the projects can determine the influence of aggregate size distribution on the manner in which GNP affects the compaction performance of asphalt mixtures in terms of the final air void ratio for the given compaction temperature and the number of compaction gyrations.


  • English


  • Status: Active
  • Contract Numbers:


  • Sponsor Organizations:

    Center for Transportation Studies

    University of Minnesota
    500 Washington Avenue SE, TSB 200
    Minneapolis, MN  United States  55118
  • Project Managers:

    Grune, Hannah

  • Performing Organizations:

    University of Minnesota, Minneapolis

    Department of Civil Engineering
    500 Pillsbury Drive, SE
    Minneapolis, MN  United States  55455-0116
  • Principal Investigators:

    Le, Jialiang

  • Start Date: 20160201
  • Expected Completion Date: 20160630
  • Actual Completion Date: 0

Subject/Index Terms

Filing Info

  • Accession Number: 01589846
  • Record Type: Research project
  • Source Agency: University of Minnesota, Minneapolis
  • Contract Numbers: CTS-2016057
  • Files: RiP
  • Created Date: Feb 4 2016 10:07AM