DIRTY AGGREGATE, WHAT DIFFERENCE DOES IT MAKE?

THE EFFECTS OF CLAY IN CONCRETE FINE AGGREGATE ON THE PROPERTIES OF CONCRETE ARE PRESENTED AND DISCUSSED. THE TWO MOST GENERALLY USED TESTS, THE LOSS BY DECANTATION AND SAND EQUIVALENT TESTS, ARE EXAMINED. THE ABILITY OF THESE TESTS TO MEASURE THE OBSERVED EFFECTS OF THE CLAY FRACTION OF AN AGGREGATE ON THE PROPERTIES OF CONCRETE IS ILLUSTRATED. THE CONCRETE PROPERTIES UNDER STUDY WERE WATER REQUIREMENT, STRENGTH, SHRINKAGE AND FREEZE-THAW DURABILITY. BOTH THE QUANTITY AND ACTIVITY OF THE CLAY FRACTION WERE FOUND TO BE INFLUENTIAL. INCREASES IN QUANTITY AND ACTIVITY OF CLAY CAUSE INCREASES IN WATER REQUIREMENT AND SHRINKAGE AND DECREASES IN STRENGTH AND DURABILITY. BECAUSE OF THE INFLUENCE OF THE ACTIVITY OF THE CLAY FRACTION, THE SAND EQUIVALENT TEST IS THE BETTER INDICATOR OF THE EFFECT ON CONCRETE OF THE CLAY FRACTION OF AN AGGREGATE. /AUTHOR/

• Record URL:
  http://onlinepubs.trb.org/Onlinepubs/hrr/1968/226/226-003.pdf
• Supplemental Notes:
  • Paper sponsored by Committee on Mineral Aggregates and presented at the 47th Annual Meeting. 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:
  • Buth, Eugene
  • Ivey, Don L
  • Hirsch, Teddy J
• Publication Date: 1968

Media Info

• Media Type: Print
• Features: Figures; References; Tables;
• Pagination: pp 26-34
• Monograph Title: Concrete Admixtures Aggregates and Durability
• Serial:
  • Highway Research Record
  • Issue Number: 226
  • Publisher: Highway Research Board

Subject/Index Terms

• TRT Terms: Clay; Compressive strength; Concrete; Concrete aggregates; Concrete tests; Durability; Fine aggregates; Freeze thaw durability; Physical properties; Sand equivalent test; Shrinkage; Water consumption
• Uncontrolled Terms: Concrete properties
• Old TRIS Terms: Decantation; Water requirements
• Subject Areas: Geotechnology; Highways; Materials;

Filing Info

• Accession Number: 00217752
• Record Type: Publication
• Files: TRIS, TRB
• Created Date: Sep 12 1994 12:00AM