TESTING FLEXIBLE PAVEMENTS UNDER NORMAL TRAFFIC LOADINGS BY MEANS OF MEASURING SOME PHYSICAL QUANTITIES RELATED TO DESIGN THEORIES

IN AN INTRODUCTION THE PAPER DISCUSSES THE ARGUMENTS THAT LED TO THE CONCLUSION THAT IT IS NECESSARY TO CARRY OUT FULL SCALE ROAD TESTS TO BE ABLE TO FORM AN OPINION ON THE PRACTICAL VALUE OF VARIOUS CALCULATION METHODS. PROPERTIES OF MATERIALS AS WELL AS DIFFERENCES BETWEEN THE LOAD SYSTEM USED IN THE MATHEMATICAL APPROACH AND THE REAL WHEEL LOAD ARE ELUCIDATED. IT IS POINTED OUT THAT AS A FIRST STAGE IN THIS STUDY A SIMPLE CONSTRUCTION /TWO LAYER SYSTEM/ AND A SIMPLE LOAD SYSTEM /SINGLE WHEEL/ HAVE TO BE PREFERRED FOR THE EXPERIMENTAL INVESTIGATION. CONDITIONS OF TESTING WERE CHOSEN IN SUCH A WAY THAT A SINGLE CONSTRUCTION THICKNESS SUFFICED AS VARIATION IN THE PROPERTIES OF THE CHOSEN ALL BITUMINOUS CONSTRUCTION COULD BE OBTAINED BY TESTING OVER THE FOUR SEASONS AT DIFFERENT TEMPERATURES. THE MEASURING TECHNIQUES ARE ELUCIDATED AS THE STRAIN GAUGES AT VARIOUS LEVELS AND THE OPTICAL DEFLECTION TECHNIQUE USED PRESENT NEW DEVELOPMENTS. DETAILS OF THE CONSTRUCTION AND OF THE LOADING SYSTEM ARE GIVEN. THE PROPERTIES OF THE MATERIALS HAVE BEEN DETERMINED BOTH IN THE FIELD BY IN SITU MEASUREMENTS (VIBRATION TECHNIQUE) AND IN THE LABORATORY, AND THE PROPERTIES DURING THE TEST RUNS ARE DISCUSSED. FROM EXISTING MATHEMATICAL METHODS FOR THE ELASTIC DESIGN THEORY GRAPHS HAVE BEEN PREPARED FOR USE OF HANDLING AND WITH A VIEW TO SIMPLIFY APPLICATION, BOTH FOR THE BURMISTER METHOD AND FOR THE SLAB METHOD (JEUFFROY). THE RESULTS OF MEASUREMENTS UNDER THE CENTRE OF LOADING ARE DISCUSSED AND A COMPARISON IS MADE FOR ALL THE PHYSICAL PROPERTIES MEASURED BETWEEN DATA AND CALCULATED VALUES ACCORDING TO THE TWO METHODS. FROM THE RESULTS CONCLUSIONS ARE DRAWN AS TO THE CORRECTNESS BY WHICH THE ELASTIC THEORIES ARE ABLE TO PREDICT ACTUAL STRESSES, STRAINS AND DEFLECTIONS IN THE ROAD CONSTRUCTION UNDER TRAFFIC. IT WAS FOUND THAT FOR THE ROAD CONSTRUCTION TESTED THE AGREEMENT BETWEEN MEASURED VALUES WAS WITHIN A FEW PERCENT OF THOSE CALCULATED ACCORDING TO BURMISTER. THE RESULTS OF SOME MEASUREMENTS TO DETERMINE THE INFLUENCE ON THE LATERAL POSITION OF THE WHEEL ARE DISCUSSED. (AUTHOR)

• Supplemental Notes:
  • Preprint VoL, PP 556-572, 11 FIG, 11 TAB, 3 REF
• Authors:
  • Nijboer, L W
• Conference:
  • Intl Conf Struct Design Asphalt Pvmts
• Publication Date: 1967-1

Subject/Index Terms

• TRT Terms: Deflection; Elasticity (Mechanics); Field tests; Flexible pavements; Loads; Materials; Optical measurement; Pavements; Physical properties; Strain (Mechanics); Strain gages; Stresses; Testing; Traffic; Vibration devices
• Old TRIS Terms: Elastic theory; Insitu methods; Pavement deflection; Strains; Vibrators
• Subject Areas: Highways; Materials; Operations and Traffic Management; Pavements;

Filing Info

• Accession Number: 00206653
• Record Type: Publication
• Files: TRIS
• Created Date: Aug 1 1994 12:00AM