MARYLAND INVESTIGATION OF CONTINUOUSLY-REINFORCED CONCRETE PAVEMENT: 1959-1964 STRAIN OBSERVATIONS

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

• Record URL:
  http://onlinepubs.trb.org/Onlinepubs/hrr/1966/112/112-005.pdf
• Supplemental Notes:
  • 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:
  • Nixdorf, Richard H
  • Lepper Jr, Henry A
• Publication Date: 1966

Media Info

• Media Type: Digital/other
• Features: Figures; References; Tables;
• Pagination: pp 82-105
• Monograph Title: Concrete pavement design
• Serial:
  • Highway Research Record
  • Issue Number: 112
  • Publisher: Highway Research Board

Subject/Index Terms

• TRT Terms: Age; Construction; Continuously reinforced concrete pavements; Cracking; Crash investigation; Experimental roads; Expressways; Material reinforcement; Pavement cracking; Percent; Size; Steel; Strain measurement; Stresses; Studies; Temperature; Temperature measurement
• Identifier Terms: Interstate 83
• Geographic Terms: Maryland
• Subject Areas: Construction; Highways; Pavements; Safety and Human Factors;

Filing Info

• Accession Number: 00205330
• Record Type: Publication
• Files: TRIS, TRB
• Created Date: Nov 10 1994 12:00AM