Aggregate-Geogrid Interaction Model Incorporating Moisture Effects

The aggregate-geogrid interaction model is a numerical model of an unsaturated granular material containing geogrid. The mechanical behavior of this system is simulated by the three-dimensional discrete-element program PFC3D. The granular material is modeled as spherical grains, and the geogrid is modeled as strings of overlapping bonded spherical balls such that the geogrid deforms in response to loads imposed by the grains, and thereby constrains the motion of the grains. The numerical model is embodied in a pavement-design package that supports creation and triaxial testing of the synthetic system. The model is being used to support a larger research initiative of the Minnesota Department of Transportation (MnDOT) to better understand and quantify the structural benefit of including geogrid in the aggregate base layer of asphalt-surface roadways. Geogrid increases the aggregate base layer modulus, which is an important property influencing the roadway performance. The base layer modulus is an input to the mechanistic-empirical flexible pavement design program MnPAVE, and its increase arising from the presence of geogrid is quantified by a geogrid gain factor. The geogrid gain factor is defined as the ratio of resilient modulus of the aggregate with geogrid to resilient modulus of the aggregate without geogrid. The geogrid gain factors for typical aggregate-geogrid roadway configurations are computed by the pavement-design package. The computed factors are sensitive to grain-size distribution, initial specimen porosity, material moisture content and confining stress.

• Supplemental Notes:
  • This paper was sponsored by TRB committee AFS70 Standing Committee on Geosynthetics.
• Corporate Authors:

  Transportation Research Board

  500 Fifth Street, NW
  Washington, DC  United States  20001
• Authors:
  • Potyondy, David
  • Siekmeier, John
  • Petersen, Lee
• Conference:
  • Transportation Research Board 95th Annual Meeting
  • Location: Washington DC, United States
  • Date: 2016-1-10 to 2016-1-14
• Date: 2016

Language

• English

Media Info

• Media Type: Digital/other
• Features: Figures; References; Tables;
• Pagination: 18p
• Monograph Title: TRB 95th Annual Meeting Compendium of Papers

Subject/Index Terms

• TRT Terms: Asphalt pavements; Discrete element method; Geogrids; Granular bases; Mathematical models; Mechanistic-empirical pavement design; Modulus of resilience; Moisture content
• Geographic Terms: Minnesota
• Subject Areas: Design; Highways; Pavements;

Filing Info

• Accession Number: 01596063
• Record Type: Publication
• Report/Paper Numbers: 16-6085
• Files: TRIS, TRB, ATRI
• Created Date: Apr 18 2016 12:29PM