IMPROVED CHARACTERIZATION MODEL FOR GRANULAR BASES

Laboratory resilient modulus tests were conducted on granular materials at stress states exceeding the materials' static shear strengths. The test results show that, above the static strength, the modulus decreases with increasing stress levels. These data were used to develop a characterization model that is a modification of the commonly used k-theta-n model. The modification consists of the addition of a stress ratio (stress/strength) parameter. The stress ratio model was used in the finite element program ILLI-PAVE to analyze typical flexible pavement sections. The analysis results are compared with similar analyses using the Mohr-Coulomb stress adjustment model normally used with ILLI-PAVE. The comparison shows that similar stress and strain patterns are predicted by both models but that the stresses predicted in the granular base by the stress ratio model appear to be more realistic. Also, the stress ratio model provides a means for analyzing the structural effects of granular materials having different shear strength characteristics.

• Record URL:
  • http://onlinepubs.trb.org/Onlinepubs/trr/1989/1227/1227-013.pdf
• Record URL:
  • https://scholar.google.com/scholar_lookup?title=IMPROVED+CHARACTERIZATION+MODEL+FOR+GRANULAR+BASES&author=R.+Elliott&author=L.+David&publication_year=1989
• Availability:
  • Find a library where document is available. Order URL: http://worldcat.org/isbn/0309048222
• Supplemental Notes:
  • This paper appears in Transportation Research Record No. 1227, Rigid and Flexible Pavement Design and Analysis: Unbound Granular Materials, Tire Pressures, Backcalculation, and Design Methods. 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:
  • Elliott, Robert P
  • David, Lourdesnathan
• Publication Date: 1989

Media Info

• Features: Figures; References; Tables;
• Pagination: p. 128-133
• Monograph Title: Rigid and flexible pavement design and analysis: unbound granular materials, tire pressures, backcalculation, and design methods
• Serial:
  • Transportation Research Record
  • Issue Number: 1227
  • Publisher: Transportation Research Board
  • ISSN: 0361-1981

Subject/Index Terms

• TRT Terms: Alternatives analysis; Computer programs; Finite element method; Flexible pavements; Granular bases; Laboratory tests; Mathematical models; Modulus of resilience; Shear strength; Stress ratio
• Old TRIS Terms: Test results
• Subject Areas: Design; Highways; Pavements; I22: Design of Pavements, Railways and Guideways;

Filing Info

• Accession Number: 00495073
• Record Type: Publication
• ISBN: 0309048222
• Files: TRIS, TRB, ATRI
• Created Date: Jun 30 1990 12:00AM