PETROGRAPHIC INSIGHTS INTO THE SUSCEPTIBILITY OF AGGREGATES TO WEAR AND POLISHING

Results from three studies confirm that a strong relation exists between the petrographic properties of an aggregate and its susceptibility to wear and polishing. Constituent mineral composition; hardness; differential hardness; porosity; grain shape, size, and distribution; and bonding between grains or crystals and matrix are all important properties that contribute to aggregate wear resistance and polish resistance. Hard, well-bonded minerals will resist wear but will eventually polish though at a slower rate than softer minerals. Loosely bonded materials will resist polishing but will wear at a rate that may render them not durable. Two subtasks in the studies revealed that an inverse relation exists between the rate of wear of an aggregate and its susceptibility to polishing. To resist both polishing and wear, an aggregate should ideally contain a high percentage of hard, coarse, angular crystals well bonded into a matrix of softer, finer grains, or the hard crystals should be well bonded together in a porous structure so that slow, gradual, irregular fracture of the crystals will occur. Based on the findings from the three studies and other research, a table has been prepared that includes suggestions for aggregate property values that will result in high resistance to both wear and polishing. /Author/

Media Info

  • Media Type: Print
  • Features: Figures; Photos; References; Tables;
  • Pagination: pp 20-27
  • Monograph Title: Bituminous materials, mixtures, and performance
  • Serial:

Subject/Index Terms

Filing Info

  • Accession Number: 00300681
  • Record Type: Publication
  • ISBN: 0309028418
  • Files: TRIS, TRB
  • Created Date: Nov 7 1979 12:00AM