A COMPARATIVE STUDY OF THE DROP-IN AND OVERLAY METHODS OF REFLECTORIZING TRAFFIC PAINTS-WITH DISCUSSION

IN THE DEVELOPMENT OF MICHIGAN'S TRAFFIC PAINT PROCUREMENT PROCEDURES IT BECAME DESIRABLE TO ESTABLISH A FIXED POLICY WITH REGARD TO THE USE OF GLASS BEADS FOR REFLECTORIZATION. TWO METHODS, DROP-IN AND OVERLAY, WERE STUDIED IN CONTROLLED FIELD TESTS ON CONCRETE AND BITUMINOUS SURFACES CONDUCTED IN MUCH THE SAME WAY AS THE ANNUAL PERFORMANCE TESTS FOR PROCUREMENT PURPOSES. TWO TOP QUALITY PAINTS, BOTH WHITE AND YELLOW, WERE APPLIED IN FOUR DIFFERENT WET FILM THICKNESSES USING THE SAME AMOUNT OF BINDER AND THE SAME OVER-ALL BEAD GRADING IN THE COMPANION STRIPES FOR EACH FILM THICKNESS. IN THE DROP-IN METHOD, 6 LB OF BEADS PER GALLON OF PAINT WERE DROPPED IN THE WET PAINT FILM IMMEDIATELY AFTER APPLICATION; IN THE OVERLAY METHOD, 4 LB OF BEADS PER GALLON OF PAINT WERE PREMIXED AND 2 LB DROPPED ON THE PREBEADED PAINT IN THE STRIPE. THE TEST WAS CONTINUED FOR MORE THAN A YEAR, WITH EVALUATIONS AT APPROXIMATELY THREE-MONTH INTERVALS. THE RESULTS INDICATED LITTLE DIFFERENCE IN THE PERFORMANCE OF PAINTS REFLECTORIZED BY THE TWO METHODS. IN MOST CASES, ANY OBSERVABLE DIFFERENCE WAS IN FAVOR OF THE DROP-IN METHOD WHEN THE TEST STRIPES WERE EVALUATED ON THE BASIS OF PERFORMANCE OVER THE ENTIRE TEST PERIOD. IT WAS ALSO FOUND THAT THICKER FILMS GAVE LONGER-LASTING STRIPES, BUT THAT LIFE WAS NOT INCREASED IN PROPORTION TO THE AMOUNT OF MATERIAL USED. /AUTHOR/

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  • Supplemental Notes:
    • Vol 36, pp 359-370, 1 FIG, 7 TAB. 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:
    • Rhodes, C C
    • Cody, L W
  • Publication Date: 1957

Media Info

  • Media Type: Digital/other
  • Monograph Title: Proceedings of the Thirty-Sixth Annual Meeting of the Highway Research Board, Washington, D.C., January 7-11, 1957
  • Serial:

Subject/Index Terms

Filing Info

  • Accession Number: 00217127
  • Record Type: Publication
  • Files: TRIS, TRB
  • Created Date: Jun 5 1972 12:00AM