MEASURING THE LOAD SUPPORTING VALUE OF FLEXIBLE PAVEMENTS

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

• Record URL:
  https://onlinepubs.trb.org/Onlinepubs/hrbproceedings/21/21-010.pdf
• Supplemental Notes:
  • Vol 21, pp 142-146, 2 FIG, 5 TAB. Distribution, posting, or copying of this PDF is strictly prohibited without written permission of the Transportation Research Board of the National Academy of Sciences. Unless otherwise indicated, all materials in this PDF are copyrighted by the National Academy of Sciences. Copyright © National Academy of Sciences. All rights reserved.
• Authors:
  • Campen, W H
  • Smith, J R
• Publication Date: 1942

Media Info

• Media Type: Digital/other
• Monograph Title: Proceedings of the Twenty-First Annual Meeting of the Highway Research Board Held at the Johns Hopkins University, Baltimore, Maryland, December 2-5, 1941
• Serial:
  • Highway Research Board Proceedings
  • Volume: 21
  • Publisher: Highway Research Board

Subject/Index Terms

• TRT Terms: Compaction; Deformation; Flexible pavements; Loads; Moisture content; Soil aggregates; Soil compaction; Subgrade (Pavements)
• Old TRIS Terms: Maximum density (Laboratory tests); Optimum moisture content; Soil aggregate mixtures
• Subject Areas: Geotechnology; Highways; Pavements;

Filing Info

• Accession Number: 00207279
• Record Type: Publication
• Files: TRIS, TRB
• Created Date: Sep 6 1971 12:00AM