DEFLECTION CRITERIA FOR FLEXIBLE PAVEMENTS

THE LONG-TERM PERFORMANCE OF A FLEXIBLE PAVEMENT IS RELATED TO THE MAGNITUDE OF THE TRANSIENT DEFLECTIONS WHICH OCCUR UNDER TRAFFIC. MEASUREMENTS MADE OVER THE PAST 15 YEARS ON EXPERIMENTAL PAVEMENTS HAVE SHOWN THAT IT IS POSSIBLE TO RELATE THE DEFLECTION MEASURED UNDER A "STANDARD" WHEEL-LOAD TO PAVEMENT LIFE IN TERMS OF THE CUMULATIVE COMMERCIAL TRAFFIC. DEFLECTION CRITERIA CURVES OF THIS TYPE HAVE BEEN DEVELOPED FOR PAVEMENTS WITH CRUSHED STONE, ROLLED ASPHALT, TARMACADAM AND CEMENTED BASES UNDER ROLLED ASPHALT SURFACINGS. THE DATA REPORTED HERE WAS COLLECTED FROM THE LABORATORIES FULL-SCALE PAVEMENT DESIGN EXPERIMENTS, AND PARTICULARLY FROM THE ALCONBURY HILL EXPERIMENT CONSTRUCTED IN 1957. THE DEFLECTION MEASUREMENTS HAVE BEEN MADE WITH THE DEFLECTION BEAM. THE DEFLECTION CRITERION CURVES FOR PAVEMENTS WITH CRUSHED STONE, ROLLED ASPHALT AND COATED MACADAM BASES ARE IDENTICAL WITHIN THE LIMITS OF THE EXPERIMENTAL ACCURACY, BUT ACCEPTABLE DEFLECTION LEVELS ARE MUCH LOWER ON PAVEMENTS WITH CEMENTED BASES. THE MANNER IN WHICH DEFLECTION CRITERION CURVES CAN BE USED TO ESTIMATE FUTURE PERFORMANCE AND FUTURE MAINTENANCE REQUIREMENTS FOR FLEXIBLE PAVEMENTS IS DESCRIBED. DETAILS OF EXPERIMENTS WITH THE DEFLECTION BEAM ARE TABULATED AND THE MAIN CONCLUSIONS ARE DISCUSSED IN TERMS OF BASE MATERIALS USED. DETAILS ARE GIVEN OF THE DEFLECTION PROGRAMME AT THE ALCONBURY HILL EXPERIMENT AND THE RESULTS ARE REVIEWED. OTHER ASPECTS DISCUSSED INCLUDE STRUCTURAL PARAMETERS AND THE DEFLECTION - PERFORMANCE RELATIONSHIP; COMPARISON WITH EARLIER RECOMMENDATIONS; AND THE APPLICATION OF DEFLECTON CRITERIA TO ROAD MAINTENANCE REQUIREMENTS. CONCLUSIONS MADE ON THE BASIS OF THE STUDY ARE LISTED.

  • Supplemental Notes:
    • TRRL REPT LR 375
  • Corporate Authors:

    Transport and Road Research Laboratory (TRRL)

    Wokingham, Berkshire  United Kingdom 
  • Authors:
    • Lister, N W
  • Publication Date: 1972

Media Info

  • Features: Figures; Photos; References; Tables;
  • Pagination: 28 p.

Subject/Index Terms

Filing Info

  • Accession Number: 00206092
  • Record Type: Publication
  • Files: TRIS, ATRI
  • Created Date: Apr 20 1974 12:00AM