DURABILITY CHARACTERISTICS OF ASPHALTIC MATERIALS - FINAL REPORT

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

  • Supplemental Notes:
    • Hpr-1(4)8 EES 300, 17-69
  • Corporate Authors:

    Ohio State University, Columbus

    190 North Oval Drive
    Columbus, OH  United States  43210

    Ohio Department of Highways

    Columbus, OH  United States  43210

    Bureau of Public Roads /US

    400 7th Street, SW
    Washington, DC  United States  20590
  • Authors:
    • Majidzadeh, K
  • Publication Date: 1969

Subject/Index Terms

Filing Info

  • Accession Number: 00210421
  • Record Type: Publication
  • Source Agency: Bureau of Public Roads /US
  • Files: TRIS
  • Created Date: Dec 22 1994 12:00AM