SOME FATIGUE CONSIDERATIONS IN THE DESIGN OF THIN PAVEMENTS

AN INTEGRAL TRANSFORM TECHNIQUE IS USED TO SOLVE FOR STRESSES AND STRAINS OCCURRING IN A HIGHWAY SUBGRADE. A SENSITIVITY ANALYSIS OF THE SOLUTION TECHNIQUE SELECTED IS STUDIED IN CONSIDERABLE DETAIL. THIS SENSITIVITY ANALYSIS INDICATED THAT THE VERTICAL COMPRESSIVE STRAIN IN THE SUB- GRADE, AND THE DEFLECTION OCCURRING IN THE HIGHWAY SYSTEM WERE PRIMARILY FUNCTIONS OF THE SUBGRADE MODULUS. THE INFLUENCE OF THE LAYERS ABOVE THE SUBGRADE ON THESE TWO RESPONSES WAS MINIMAL. THE TANGENTIAL STRAIN ON THE UNDERSIDE OF THE ASPHALTIC CONCRETE WAS, HOWEVER, INFLUENCED BY THE RESILIENT MODULI OF EACH OF THE VARIOUS LAYERS. THE FINAL PHASE INVESTIGATED THE EFFECT THAT CHANGING LEGAL AXLE WEIGHTS WOULD PRODUCE IN THE FATIGUE LIFE OF A THIN PAVEMENT STRUCTURE. THIS INDICATED THAT INCREASES IN THE AXLE WEIGHTS WOULD REDUCE THE FATIGUE LIFE FROM 10 TO 20 PERCENT FOR FALL LOADING CONDITIONS AND 15 TO 30 PERCENT FOR SPRING CONDITIONS. THE TYPE OF ANALYSIS CARRIED OUT HAS PROMISE FOR ADOPTION AS A DESIGN PROCEDURE, IF CERTAIN PROBLEMS CAN BE RESOLVED. /RATAOC/

• Supplemental Notes:
  • 332 P, 185 FIG, 43 TAB, 41 REF, 6 APP.
• Corporate Authors:

  University of Saskatchewan, Canada

  Saskatoon, Saskatchewan  Canada  S7N 0W0
• Authors:
  • MacLeod, D R
• Publication Date: 1971-3

Subject/Index Terms

• TRT Terms: Axle load force; Deformation curve; Fatigue (Mechanics); Pavement layers; Subgrade (Pavements)
• Uncontrolled Terms: Fatigue life; Pavement structure
• Subject Areas: Highways; Pavements;

Filing Info

• Accession Number: 00206597
• Record Type: Publication
• Source Agency: Roads & Transportation Assoc /Canada
• Files: TRIS
• Created Date: Aug 7 1972 12:00AM