A Device for Measuring Shape and Angularity of Fine Granular Materials

The inherent particle characteristics of aggregates influencing the strength of hot mix asphalt (HMA) pavements inlcude particle size, particle size ditribution, particle shape, angularity, hardness, and surface roughness. This study aims at revising the Fine Aggregate Angularity test, adopted as a Superpave consensus test for determination of fine aggregate shape and angularity due to its limitations. From the results of this study a better measure of fine aggregate morphology and inherent particle characteristics can be obtained by measuring the flow rate of the material through a hopper. To determine the effect of inherent particle characteristics on flow rate, a wide range of materials were tested. These materials ranged from manufactured sands and glass beads to natural sands. To achieve the objective of quantifying shape and angularity, a new technique was developed utilizing the image analyzer. Two shape parameters, namely Shape Factor and Angularity Factor were determined for various materials. Shape and Angularity Facor were correlated with flow rate. Overall, the results indicate that as shape and angularity of particles increase, the flow rate decreases. A good correlation between drained shear strength properties and the flow rates measured in the cone was also established. Therefore, index tests such as flow rate through a flow cone (hopper) have the potential to be used to estimate the drained monotonic strength of particulate materials, as well as determine the shape and angularity of the aggregates.

  • Availability:
  • Authors:
    • Sukumaran, Beena
    • Ashmawy, Alaa K
    • Mehta, Yusuf
  • Publication Date: 2006-1

Language

  • English

Media Info

  • Media Type: Print
  • Features: Appendices; Figures; References; Tables;
  • Pagination: pp 130-141
  • Serial:

Subject/Index Terms

Filing Info

  • Accession Number: 01054613
  • Record Type: Publication
  • Files: TRIS
  • Created Date: Jul 20 2007 9:41PM