DEFLECTION AND CURVATURE AS CRITERIA FOR FLEXIBLE PAVEMENT DESIGN AND EVALUATION

THE EXCESSIVE PLASTIC DEFORMATION OF THE SUBGRADE AND THE FATIGUE CRACKING OF ASPHALT SURFACES ARE TWO MAJOR CAUSES OF PAVEMENT FAILURES. A METHOD TO PRECLUDE SUCH FAILURES IS TO CONSIDER THE PAVEMENT AS A THREE- LAYER ELASTIC SYSTEM BY LIMITING THE VERTICAL COMPRESSIVE STRAIN ON THE SURFACE OF THE SUBGRADE AND THE HORIZONTAL TENSILE STRAIN AT THE BOTTOM OF THE ASPHALT-BOUND LAYER. THE DISADVANTAGE IS THAT THESE STRAINS CANNOT BE EASILY MEASURED IN THE FIELD, SO THE ADEQUACY OF THE METHOD CANNOT BE PROPERLY EVALUATED. THE PURPOSE IS TO FIND THE RELATIONSHIPS AMONG DEFLECTION, CURVATURE, COMPRESSIVE STRAIN ON THE SUBGRADE, AND TENSILE STRAIN IN THE ASPHALT LAYER SO THAT DEFLECTION AND CURVATURE, INSTEAD OF COMPRESSIVE AND TENSILE STRAINS, CAN BE USED AS CRITERIA FOR PAVEMENT DESIGN AND EVALUATION. THESE RELATIONSHIPS ARE EXPRESSED AS DIMENSIONLESS RATIOS AND PRESENTED IN TABULAR FORMS. THE APPLICATION OF THESE TABLES TO PAVEMENT DESIGN AND EVALUATION IS ILLUSTRATED. IT IS SHOWN THAT, FOR THINNER PAVEMENTS, CURVATURE IS A BETTER INDICATOR OF THE COMPRESSIVE STRAIN ON THE SUBGRADE, WHILE FOR THICKER PAVEMENTS, DEFLECTION IS THE BETTER INDICATOR. THE TENSILE STRAIN IN THE ASPHALT LAYER IS RELATED TO THE CURVATURE AND THE THICKNESS OF THE ASPHALT LAYER. /AUTHOR/

• Record URL:
  http://onlinepubs.trb.org/Onlinepubs/hrr/1971/345/345-001.pdf
• Supplemental Notes:
  • Paper sponsored by Committee on Strength and Deformation Characteristics of Pavement Sections and presented at the 50th Annual Meeting. 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:
  • Huang, Y H
• Discussers:
  • Vaswani, N K
• Publication Date: 1971

Media Info

• Media Type: Print
• Features: Appendices; Figures; References; Tables;
• Pagination: pp 1-14, 5 FIG,
• Monograph Title: Highway soils engineering
• Serial:
  • Highway Research Record
  • Issue Number: 345
  • Publisher: Highway Research Board

Subject/Index Terms

• TRT Terms: Asphalt; Compression; Curvature; Deflection; Elasticity (Mechanics); Failure; Fatigue (Physiological condition); Fracture mechanics; Pavement design; Pavements; Plastic deformation; Strain (Mechanics); Subgrade (Pavements); Surfaces; Tension
• Uncontrolled Terms: Criteria; Relationships
• Old TRIS Terms: Layered system mechanics; Pavement deflection; Strains
• Subject Areas: Highways; Pavements;

Filing Info

• Accession Number: 00205931
• Record Type: Publication
• Files: TRIS, TRB
• Created Date: Sep 13 1971 12:00AM