The purpose of this investigation was to develop a grading specification that would provide a more satisfactory pavement and be more compatible with source characteristics so they would lessen production and construction difficulties. Conservation of materials, cost savings, decreased asphalt requirements, higher friction surfaces, and mineral filler elimination were associated benefits that appeared to be realizeable as the study progressed. Bituminous pavement mixtures using Yellowstone River aggregates exhibited characteristics associated with over-sanding when produced under the Standard Specifications. This specification nominally limited the -40M fraction to a maximum of 25%, however waivers generally allowed 30% and this figure was often exceeded in production. The high sand fraction in turn required a substantial proportion of fine particles (-80 & -200M) to fill void spaces in the sand. In order to ascertain gradation characteristics of the natural gravel deposits, several sites along the river were chosen for statistical analyses. Data was taken from the files of completed projects which were located at more or less equal distances apart and which provided a large number of samples.

  • Corporate Authors:

    Montana Department of Highways

    Materials Bureau, 2701 Prospect Avenue
    Helena, MT  United States  59620

    Federal Highway Administration

    Office of Research and Development, 1200 New Jersey Avenue, SE
    Washington, DC  United States  20590
  • Authors:
    • Weber, S F
    • Braut, A
  • Publication Date: 1975-5

Media Info

  • Pagination: 92 p.

Subject/Index Terms

Filing Info

  • Accession Number: 00151808
  • Record Type: Publication
  • Source Agency: National Technical Information Service
  • Report/Paper Numbers: Res. Project-7924 Final Rpt., FHWA/RD/M-0342
  • Created Date: May 11 1977 12:00AM