GEL PERMEATION CHROMATOGRAPHY DATA ON ASPHALTS BEFORE AND AFTER SERVICE IN PAVEMENTS AND DISCUSSION

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

• Supplemental Notes:
  • Vol 39, pp 683-702, 11 FIG, 2 TAB, 9 REF
• Authors:
  • Bynum, D
  • Traxler, R N
• Conference:
  • Association of Asphalt Paving Technologists Proc
• Publication Date: 1970

Subject/Index Terms

• TRT Terms: Asphalt; Before and after studies; Bituminous pavements; Chromatography; Gels; Permeability; Rheological properties
• Subject Areas: Highways; Materials;

Filing Info

• Accession Number: 00211673
• Record Type: Publication
• Files: TRIS
• Created Date: Jul 25 1971 12:00AM