COMPARISON BETWEEN FIELD MEASUREMENTS AND ELASTIC AND NON-LINEAR FINITE ELEMENT SOLUTIONS OF THE FLEXIBILITY SECTIONS OF THE S12/2 EXPERIMENTAL ASPHALT PAVEMENT

THIS REPORT EXAMINES THE SUITABILITY OF THE APPLICATION OF LINEAR ELASTIC AND NON-LINEAR ELASTIC FINITE ELEMENT COMPUTER PROGRAMS TO THE PREDICTION OF THE CRITICAL STRAINS IN THE BITUMINOUS LAYERS OF AN ASPHALT PAVEMENT CONSTRUCTION. THE CRITICAL STRAINS WERE COMPARED BOTH FROM PRACTICAL MEASUREMENTS AND THEORETICAL PREDICTIONS OVER A RANGE OF SURFACING THICKNESSES VARYING FROM 25 MM TO 100 MM FOR A CONTINUOUSLY GRADED ASPHALTIC CONCRETE AND A GAP-GRADED BITUMINOUS SURFACING MIXTURE. THE BASE LAYER, WHICH PREDOMINANTLY DETERMINES THE BEHAVIOR OF THE SURFACING, CONSISTS OF A 300 MM THICK UNBOUND CRUSHER- RUN. THE NECESSITY OF TAKING ACCOUNT OF THE STRESS NON-LINEARITY OF THIS GRANULAR LAYER IS CLEARLY DEMONSTRATED BY THE RESULTS PRESENTED. IT IS SHOWN THAT THE MAGNITUDE OF THE MAXIMUM TENSILE STRAIN AT THE SURFACING-BASE INTERFACE IS SIGNIFICANTLY INFLUENCED BY SURFACING TYPE, SURFACING TEMPERATURE, AND SURFACING THICKNESS VARIATIONS. THE INFLUENCE OF WHEEL LOADS AND TIRE PRESSURE ON THE MAXIMUM TENSILE STRAINS IS DISCUSSED AND PRACTICAL CONFIRMATION IS OBTAINED OF THE CONCEPT THAT THE TIRE CONTACT PRESSURE IS THE DOMINANT TRAFFIC FACTOR WHICH DETERMINES THE MAXIMUM TENSILE STRAIN UNDER THIN SURFACINGS, THE WHEEL LOAD BEING OF SECONDARY IMPORTANCE. THE STUDY REVEALS THAT VEHICLES WITH DUAL WHEELS, AS OPPOSED TO SINGLE WHEEL, UNDER EQUIVALENT LOADING CONDITIONS REDUCE THE MAXIMUM TENSILE STRAIN UNDER THE SURFACING, WHEN THE SURFACING THICKNESS IS IN THE ORDER OF 100 MM OR GREATER. FINALLY, PREDICTIONS ARE MADE OF THE MOST PROBABLE VALUES OF MAXIMUM TENSILE STRAIN IN THE DIFFERENT SURFACINGS, OVER A WIDE RANGE OF ENVIRONMENTAL, TRAFFIC, AND STRUCTURAL CONDITIONS WHICH ARE MOST LIKLEY TO EXIST AT THE EXPERIMENTAL PAVEMENT DURING ITS SERVICE LIFE. /AUTHOR/

  • Corporate Authors:

    Nat Inst Road Research /S Africa

    ,    
  • Authors:
    • Freeme, C R
  • Publication Date: 1971-11

Media Info

  • Features: Figures; References; Tables;
  • Pagination: 34 p.

Subject/Index Terms

Filing Info

  • Accession Number: 00206050
  • Record Type: Publication
  • Files: TRIS
  • Created Date: May 7 1973 12:00AM