INFLUENCES ON THE PARTICLE SIZE DISTRIBUTION OF BITUMINOUS MIXTURES

EINFLUESSE AUF DIE KORNZUSAMMENSETZUNG BITUMINOESER GEMISCHE

THE AUTHOR REPORTS ON EXPERIMENTS CARRIED OUT FOR DETERMINING VARIATIONS IN THE PARTICLE SIZE DISTRIBUTION OF A GRAVEL-SAND MIXTURE WITH 6%, 8% AND 10% BITUMEN 300, AND OF ROLLED ASPHALT WITH A LARGE PROPORTION OF CHIPPINGS 0/12 MM, IN RELATION TO THE TYPE OF COMPACTION METHOD AND ROCK STRUCTURE. COMPACTION IS CARRIED OUT WITH THE MARSHALL HAMMER AS WELL AS WITH PRESSURES OF 1.3 AND 5 KN/SQ CM, VIBRATION COMPACTING WITH EXTERNAL VIBRATOR AV 400/3 AND ROLLING WITH THE SURFACE TESTER AFTER EWERS. RESULTS SHOW THAT THE GRAVEL-SAND MIXTURE HAD A REDUCTION IN THE PROPORTION OF CHIPPINGS, 73% TO 60%, AFTER THE FIRST COMPACTION PROCESS, THE SECOND COMPACTION PRODUCED A REDUCTION TO 47% AND THE PROPORTION OF FILL HAD INCREASED FROM 0.5% TO 6.8%. THE BINDER CONTENT OF 6% HAD NO SIGNIFICANT INFLUENCE ON THE DEGREE OF PARTICLE CRUSHING. A SIGNIFICANT REDUCTION OF PARTICLE CRUSHING BY COMPACTION COULD BE ESTABLISHED ONLY WHEN THE BINDER CONTENT WAS 8% AND 10%. ROLLED ASPHALT 0/12 MM SHOWED A SMALLER CHANGE IN THE PARTICLE DISTRIBUTION, A NEW FORMATION OF FILLER FOLLOWED HOWEVER IN THE ORDER OF ABOUT 1%. FURTHER POSSIBILITIES OF VARIATIONS IN THE STIPULATED PARTICLE SIZE DISTRIBUTION CAN OCCUR DUE TO FAILURE IN SCREENING IN THE MIXING PLANT, BREAKDOWN OF DOSING EQUIPMENT, INACCURATE SCREENING AS WELL AS DUE TO PROCESSING GRAVELLY SANDS IN A JET FLAME DRYER (ABOUT 1150 DEGREE K) OWING TO EXCESS PRESSURES UP TO 3 KN/SQ CM. THIS IS SUFFICIENT TO DESTROY SOFT ROCK, SO THAT THERE IS ALSO A CONSIDERABLE NEW FORMATION OF FILLER MATERIAL IN THE DRYING DRUM.

  • Corporate Authors:

    Transpress VEB Verlag fuer Verkehrswesen

    Franzoesische Strasse 13/14, Postfach 1235
    108 Berlin,   Germany 
  • Authors:
    • MAY, O E
  • Publication Date: 1978-4

Language

  • German

Media Info

  • Pagination: 132-4
  • Serial:
    • Strasse
    • Volume: 18
    • Issue Number: 4

Subject/Index Terms

Filing Info

  • Accession Number: 01289094
  • Record Type: Publication
  • Source Agency: Forschungsgesellschaft für Straßen- und Verkehrswesen (FGSV)
  • Files: ITRD
  • Created Date: Nov 21 2010 1:37AM