ULTRASONIC MODULI OF ASPHALT CONCRETE

THERE HAS BEEN A NEED FOR A NONDESTRUCTIVE, DYNAMIC TECHNIQUE FOR EVALUATING CERTAIN "ELASTIC" CONSTANTS OF ASPHALT PAVING MATERIALS. IN THIS STUDY, A METHOD IS DEVELOPED BY WHICH THE DYNAMIC E-MODULUS, G-MODULUS, AND POISSON'S RATIO OF COMPACTED ASPHALT- AGGREGATE SPECIMENS ARE DETERMINED FROM MEASUREMENT OF THE PROPAGATION VELOCITIES OF PULSED ULTRASONIC SHEAR AND COMPRESSIONAL WAVES THROUGH THE TEST MATERIAL. THIS TEST PROCEDURE PROVED TO BE EASILY AND RAPIDLY PERFORMED ON STANDARD HVEEN-GYRATORY SPECIMENS. THE RESULTS OBTAINED COMPARED FAVORABLY WITH THOSE REPORTED BY OTHER INVESTIGATORS USING DIFFERENT PROCEDURES. A BRIEF STUDY OF A SINGLE ASPHALT-AGGREGATE MIXTURE, USING A VARIETY OF ASPHALT AND VOID CONTENTS, RESULTED IN THE FOLLOWING OBSERVATIONS: (A) AN INCREASE IN THE TEMPERATURE OF THE TEST MATERIAL RESULTED IN A DECREASE OF THE VALUES OF BOTH THE DYNAMIC E- AND G-MODULI; (B) MAXIMUM MODULI OCCURRED AT AN "OPTIMUM" ASPHALT CONTENT FOR WAVE TRANSMISSION OF 6 PERCENT; (C) THE DYNAMIC POISSON'S RATIO INCREASED DIRECTLY WITH INCREASED ASPHALT CONTENT OF THE SPECIMENS; (D) AT TEMPERATURES GREATER THAN APPROXIMATELY 100 F, POISSON'S RATIOS INCREASED RAPIDLY TOWARD THE THEORETICAL MAXIMUM OF 0.50; AND (E) THE AMOUNT OF VOIDS CONTAINED IN A COMPACTED SPECIMEN HAD ONLY A MINOR INFLUENCE ON THE RATE OF WAVE TRANSMISSION THROUGH THE SPECIMENS AT LOW TEMPERATURES, BUT ABOVE 80 F THIS INFLUENCE WAS MORE PRONOUNCED. /AUTHOR/

Media Info

  • Media Type: Print
  • Features: Figures; References; Tables;
  • Pagination: pp 8-21
  • Monograph Title: Asphalt mixture characterization and asphalt grading
  • Serial:

Subject/Index Terms

Filing Info

  • Accession Number: 00211769
  • Record Type: Publication
  • Files: TRIS, TRB
  • Created Date: Apr 2 1973 12:00AM