EVALUATION OF MICROAGGREGATES BY SMITH TRIAXIAL TEST

BITUMINOUS CONCRETE MIXES USUALLY CONSIST OF BINDER, COARSE AGGREGATE, FINE AGGREGATE, AND MINERAL FILLER. BECAUSE THE FUNCTION OF THE FILLER IS NOT JUST TO FILL THE VOIDS, BUT TO A GREAT EXTENT ALSO DICTATE THE PHYSICAL AND OTHER CHARACTERISTICS OF THE MIX, A MORE DESCRIPTIVE AND PRECISE NAME FOR A FILLER IS MICROAGGREGATE. THE STUDY INCLUDED FIVE MICROAGGREGATES: LIMESTONE, HYDRATED LIME, HYDRITE (CLAY), ASBESTOS, AND QUARTZ. THE QUARTZ MICROAGGREGATE WAS FURTHER TESTED USING THREE DIFFERENT GRADATIONS. ALL MICROAGGREGATES WERE INCORPORATED IN A STANDARD MASSACHUSETTS DENSE-GRADED BITUMINOUS CONCRETE MIX. THE COARSE AGGREGATE RHYOLITE AND THE FINE AGGREGATE (SAND) WERE KEPT CONSTANT IN ALL EXPERIMENTS. VARIOUS ASPHALT CONTENTS WERE USED. THE SMITH TRIAXIAL CELL WAS ADOPTED IN THE STRENGTH EVALUATION OF ALL MIXES. THE SPECIMENS WERE COMPACTED IN LAYERS USING A KNEADING COMPACTOR TO SIMULATE ULTIMATE DENSIFICATION UNDER TRAFFIC. ALL MIXES EXCEPT THOSE CONTAINING ASBESTOS HAD RELATIVELY LOW VOID CONTENTS AFTER THE KNEADING COMPACTION. THESE CASES WERE ACCOMPANIED BY LOW STRENGTH. MIXES CONTAINING THREE QUARTZ MICROAGGREGATES SHOWED HIGHER STRENGTH WHEN THE GRADATION OF THE QUARTZ WAS CLOSE TO FULLER'S MAXIMUM DENSITY CURVE. /AUTHOR/

• Record URL:
  • http://onlinepubs.trb.org/Onlinepubs/hrbbulletin/329/329-005.pdf
• Supplemental Notes:
  • Distribution, posting, or copying of this PDF is strictly prohibited without written permission of the Transportation Research Board of the National Academy of Sciences. Unless otherwise indicated, all materials in this PDF are copyrighted by the National Academy of Sciences. Copyright © National Academy of Sciences. All rights reserved
• Authors:
  • Tons, Egons
  • Henault, Gilles G
• Conference:
  • Symposium on mineral fillers for bituminous mixtures
  • Location: Washington DC, United States
  • Date: 1962-1-12 to 1962-1-8
• Publication Date: 1962

Media Info

• Media Type: Print
• Features: Appendices; Figures; References; Tables;
• Pagination: pp 48-63
• Monograph Title: Symposium on mineral fillers for bituminous mixtures
• Serial:
  • Highway Research Board Bulletin
  • Issue Number: 329
  • Publisher: Highway Research Board

Subject/Index Terms

• TRT Terms: Aggregate gradation; Asbestos; Asphalt concrete; Asphalt content; Bituminous mixtures; Calcium hydroxide; Clay; Coarse aggregates; Compaction; Fillers (Materials); Fine aggregates; Limestone aggregates; Limestone fillers; Mineral fillers; Quartz; Triaxial shear tests; Void ratios
• Old TRIS Terms: Asbestos fillers; Hydrated lime fillers; Microaggregate
• Subject Areas: Highways; Materials;

Filing Info

• Accession Number: 00210841
• Record Type: Publication
• Files: TRIS, TRB, ATRI
• Created Date: Aug 5 1994 12:00AM