THE NATURE AND EFFECTS OF SURFACE COATINGS ON COARSE AGGREGATES

SURFACE COATINGS WHICH ARE SOMETIMES FOUND ON COARSE AGGREGATES ARE DISCUSSED INCLUDING (1) STONE DUST, (2) CLAY OR SILT, (3) ORGANIC COATINGS, (4) ALKALI COATINGS, (5) BITUMINOUS OIL IMPREGNATIONS AND COATINGS, (6) CALCAREOUS INCRUSTATIONS, (7) SUGAR COATINGS, AND (8) MISCELLANEOUS. AVAILABLE TESTS INDICATE THAT STONE DUST MAY DECREASE THE STRENGTH OF CONCRETE UP TO 2 PERCENT FOR EACH 1 PERCENT OF STONE DUST IN THE MIXTURE. CLAY ADMIXTURES SEEM NOT TO BE HARMFUL IN LEAN MIXTURES OF CONCRETE BUT CAUSE DECREASE IN STRENGTH IN RICH MIXTURES. WHEN OCCURRING AS A COATING NOT EASILY REMOVED, CLAY PROBABLY PREVENTS PROPER ADHESION. BITUMINOUS OIL COATINGS OF THE NATURE AND EXTENT STUDIED DECREASED THE STRENGTH OF THE CONCRETE. THIS MAY OR MAY NOT BE SERIOUS, DEPENDING UPON THE PERCENTAGE OF SURFACES COATED. ALKALI COATINGS ARE NOT DEFINITELY PROVEN TO BE HARMFUL. SUGAR COATINGS ARE MOST DECIDELY HARMFUL AS ARE ALSO COATINGS OF ORGANIC MATTER. MISCELLANEOUS COATINGS INCLUDE COAL DUST AND DIRT FROM IMPROPERLY CLEANED RAILROAD CARDS. THERE IS A DEARTH OF INFORMATION ON THE EFFECT OF SURFACE COATINGS AND THE DESIRABILITY OF INVESTIGATIONS ON THIS SUBJECT IS STRONGLY INDICATED. MR. MIESENHELDER REPORTS THAT CRUSHED STONE SURFACE COATINGS OF THIS TYPE WERE FOUND AND TESTED IN INDIANA. THE RESULTS CONFIRM THOSE OF THE ORIGINAL INVESTIGATION. MR. KELLY EMPHASIZES THAT THE RESULTS SUGGEST THAT OIL COATINGS ON COARSE AGGREGATE FOR CONCRETE MAY BE VIEWED WITH SOME SUSPICION. /AUTHOR/

  • Supplemental Notes:
    • Vol 12, Pt1, PP 305-319, 3 TAB, 4 REF
  • Authors:
    • Goldbeck, A T
    • Miesenhelder, P D
    • Kelley, E F
  • Publication Date: 1933

Media Info

  • Monograph Title: Proceedings of the Twelfth Annual Meeting of the Highway Research Board Held at Washington, D.C. December 1-2, 1932. Part I: Reports of Research Committees and Papers
  • Serial:

Subject/Index Terms

Filing Info

  • Accession Number: 00217829
  • Record Type: Publication
  • Files: TRIS, TRB
  • Created Date: Jun 1 1971 12:00AM