EXPERIENCES WITH GYRATORY TESTING MACHINE

THE STUDIES PERFORMED AT WEST VIRGINIA UNIVERSITY, PROBLEMS ENCOUNTERED WITH THE EQUIPMENT, TENTATIVE CONCLUSIONS REACHED FROM THE RESULTS, AND THE PRESENT TREND AND FUTURE EXPECTATIONS OF THE WEST VIRGINIA UNIVERSITY RESEARCH WITH THE GYRATORY TESTING MACHINE ARE DESCRIBED. THE OPERATIONAL ASPECTS OF THE MODEL 4-C GYRATORY TESTING MACHINE ARE DISCUSSED. COMPARATIVE COMPACTION STUDIES INDICATE THAT THE GYRATORY TESTING MACHINE DOES PROVIDE A METHOD OF COMPACTION WHICH WILL GIVE REPRODUCIBLE RESULTS AND THE METHOD OF SAMPLE PREPARATION DOES INFLUENCE THE OBTAINED RESULTS. THE DESIGN ASPHALT CONTENT IS DETERMINED BY SELECTING AN ASPHALT CONTENT 3.5 PERCENT BELOW THAT WHERE FLUSHING OCCURS AS INDICATED BY THE WIDENING OF THE GYROGRAPH. THE DESIGN APPROACH PRESENTED BY KALLAS WAS VERIFIED WITHIN CERTAIN LIMITATIONS. TEST RESULTS OBTAINED IN ESTABLISHING THE KALLAS CRITERION INDICATE THAT THE OBTAINED ASPHALT CONTENTS ARE ESSENTIALLY THE SAME AS THOSE DETERMINED BY THE MARSHALL AND HVEEM METHOD OF MIX DESIGN AND APPARENTLY PROVIDE DESIRABLE AIR VOID CONTENTS. THE PROBLEMS ASSOCIATED WITH THE USE OF THE FIXED ROLLER IN THE DESIGN OF BITUMINOUS MIXTURE ARE SUMMARIZED' /1/ THE FIXED- STRAIN METHOD OF TESTING MAY NOT BE COMPATIBLE TO FIELD COMPACTION BECAUSE OF THE SAMPLE RESTRAINT IN THE MOLD, /2/ THE GYROGRAPH DOES NOT PROVIDE ADEQUATE SENSITIVITY, /3/ WIDENING OF THE GYROGRAPH TO DETERMINE THE DESIGN ASPHALT CONTENT IS DEPENDENT ON MATERIAL TYPE AND GRADATION AND CONSEQUENTLY, DOES NOT EVALUATE THE RELATIVE STABILITY OF DIFFERENT MIXTURES, AND /4/ THE MECHANISM OF FLUSHING WITH FIXED-STRAIN OPERATION IS ENTIRELY DEPENDENT ON THE WEIGHTS OF THE MOLD AND MOLD CHUCK WHICH BECOME MORE CRITICAL AS THE ANGLE OF GYRATION IS INCREASED REFERENCES' DEVELOPMENT OF THE GYRATORY TESTING MACHINE AND PROCEDURES FOR TESTING OF BITUMINOUS PAVING MIXTURES, U.S. ARMY ENGINEER WATERWAYS EXPERIMENT STATION, VICKSBURG, MISS., TECH. REPT. NO. 3-595, 1962 GYRATORY TESTING MACHINE PROCEDURES FOR SELECTING THE DESIGN ASPHALT CONTENT OF PAVING MIXTURES, B.F. KALLAS, PAPER PRESENTED AT 1964 ANN. MTG. AAPT. USE OF A GYRATORY TESTING MACHINE IN EVALUATING BITUMINOUS MIXTURES, H.W. BUSCHING AND W.H. GOETZ, HIGHWAY RESEARCH RECORD NO. 50, PP. 19-43, 1964. STABILITY RELATIONSHIPS OF GYRATORY-COMPACTED BITUMINOUS MIXTURES, H.W. BUSCHING, M.S.C.E. THESIS, PURDUE UNIVERSITY, 1963. MECHANICAL PROPERTIES OF BITUMINOUS PAVING MIXTURES, J.F. GOODE, UNPUB. REPORT TO HIGHWAY RESEARCH BOARD COMMITTEE, J.F. GOODE, DEPARTMENT OF MATERIALS AND CONSTRUCTION, 1964. THE GYRATORY METHOD OF MOLDING ASPHALTIC CONCRETE TEST SPECIMENS, ITS DEVELOPMENT AND CORRELATION WITH FIELD COMPACTION METHODS, LAWRENCE ORTOLANI AND HARRY A. SANBERG, JR., A TEXAS HIGHWAY DEPARTMENT PROCEDURE, PROX. AAPT, VOL. 21, 1952.

Media Info

  • Media Type: Print
  • Features: Figures; References; Tables;
  • Pagination: pp164-189
  • Monograph Title: Surface treatments, bituminous mixtures and pavements
  • Serial:

Subject/Index Terms

Filing Info

  • Accession Number: 00210273
  • Record Type: Publication
  • Files: TRIS, TRB
  • Created Date: Dec 12 1994 12:00AM