STRUCTURAL DETERIORATION OF TEST PAVEMENTS: FLEXIBLE

THE TREND OF SERVICEABILITY OF FLEXIBLE PAVEMENTS WAS OBSERVED WITH TIME OR LOAD APPLICATION. THE THREE ELEMENTS OF SERVICEABILITY OBSERVED AT THE AASHO ROAD TESTS WERE SLOPE VARIANCE (MEASURE OF LONGITUDINAL ROUGHNESS), RUTTING IN THE WHEEL PATHS, AND CRACKING AND PATCHING. THE EXTENT TO WHICH EACH OF THESE ELEMENTS AFFECTED THE SERVICEABILITY WAS DETERMINED FROM A GIVEN EQUATION. RESULTS SHOW THAT THE PAVEMENT IN THE VARIOUS LOOPS HEAVED APPROXIMATELY 0.4 INCHES DURING THE WINTER WITH THE EDGES RISING ABOUT 0.6 INCHES AND THE INTERIOR PORTION ABOUT 0.3 INCHES. MOST OF THIS HEAVING WAS ATTRIBUTED TO EXPANSION OF THE EMBANKING SOIL. RUTTING OF THE PAVEMENT WAS DUE PRINCIPALLY TO DECREASES IN THICKNESS OF THE COMPONENT LAYERS. ONLY 20 PERCENT OF THE CHANGE IN THICKNESS OF THE SURFACING AND 4 PERCENT OF THE CHANGE IN SUBBASE THICKNESS WAS ACCOUNTED FOR BY INCREASES IN DENSITY OF THE MATERIALS. THE PRESENCE OF SLIGHTLY MORE MOISTURE IN THE GRADULAR MATERIALS IN THE SPRING MONTHS WAS RESPONSIBLE FOR THE LOW STRENGTH AND WAS A MAJOR CONTRIBUTING FACTOR FOR THE POOR PERFORMANCE OF FLEXIBLE PAVEMENT SECTIONS AT THIS TIME. THE MARKED DECREASES IN THE STRENGTH (CBR) OF THE GRAVEL SAND SUBBASE DURING THE SPRING WAS NOT EXPLAINED BY CHANGE IN ITS MOISTURE CONTENT. IN SECTIONS THAT SURVIVED THE TEST, THE RATE OF DEVELOPMENT OF RUTTING DURING THE FIRST YEAR OF TRAFFIC GENERALLY EXCEEDED THE RATE OBSERVED DURING THE SECOND YEAR.

• Record URL:
  http://onlinepubs.trb.org/Onlinepubs/sr/sr73/73-011.pdf
• Supplemental Notes:
  • pp 173-185, 11 FIG, 2 TAB 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
• Corporate Authors:

  Highway Research Board

  2101 Constitution Avenue, NW
  Washington, DC    20418

  Transportation Research Board

  500 Fifth Street, NW
  Washington, DC  United States  20001
• Authors:
  • Benkelman, A C
• Conference:
  • Highway Research Board Conference on the AASHO Road Test
  • Location: St Louis MO, United States
  • Date: 1962-5-16 to 1962-5-18
• Publication Date: 1962

Media Info

• Monograph Title: THE AASHO ROAD TEST - PROCEEDINGS OF A CONFERENCE HELD MAY 16-18, 1962, ST. LOUIS, MISSOURI
• Serial:
  • Highway Research Board Special Report
  • Issue Number: 73
  • Publisher: Highway Research Board

Subject/Index Terms

• TRT Terms: California bearing ratio; Flexible pavements; Pavement performance; Plastic deformation; Serviceability; Slopes; Subbase materials; Variance
• Identifier Terms: AASHO Road Test
• Subject Areas: Design; Highways; Pavements;

Filing Info

• Accession Number: 00207115
• Record Type: Publication
• Files: TRIS, TRB
• Created Date: Aug 26 1970 12:00AM