INTERIM REPORT-SKID RESISTANCE AND WEAR PROPERTIES OF AGGREGATES FOR PAVING MIXTURES

THE SKID RESISTANCE AND WEAR PROPERTIES OF 20 REPRESENTATIVE AGGREGATES HAVE BEEN INVESTIGATED. A 36-INCH DIAMETER CIRCULAR TRACK MACHINE WAS DEVELOPED FOR POLISHING 6-INCH DIAMETER BITUMINOUS PAVEMENT SAMPLES MADE FROM SELECTED AGGREGATES, AND A JAR MILL APPARATUS, USING FLINT PEBBLES, WAS USED TO CLASSIFY AGGREGATES AS TO THEIR WEAR PROPERTIES. SKID RESISTANCE, AS MEASURED WITH THE BRITISH PORTABLE TESTER, WAS DETERMINED AFTER INCREMENTAL TIME INTERVALS OF WEAR AND POLICH TO CLASSIFY AND RATE THE AGGREGATES. SANDSTONE AND SYNTHETIC LIGHTWEIGHT AGGREGATE SHOW HIGH SKID RESISTANCE; ANOTHER SYNTHETIC AGGREGATE, GNEISS, GRANITE, CRUSHED GRAVEL, AND SLATE-TYPE AGGREGATES SHOW MEDIUM TO HIGH SKID RESISTANCE; AND DIABASE, POLISHED GRAVEL, AND LIMESTONES SHOW MEDIUM TO LOW SKID RESISTANCE. NO GENERAL CORRELATION FOR ALL AGGREGATES, WAS FOUND BETWEEN SKID RESISTANCE AND PHYSICAL PROPERTIES. FOR THE LIMESTONE AGGREGATES, A DIRECT PROPORTION IS IMPLIED BETWEEN SIGNIFICANT AMOUNTS OF SANDSIZE INSOLUBLE RESIDUES AND SKID RESISTANCE. AN AGGREGATE HAVING A MIXED COMPOSITION OF HARD AND SOFT MINERALS, AS DETERMINED BY PETROGRAPHIC ANALYSIS, PRODUCES A HIGHER SKID RESISTANCE THAN ONE HAVING ONE TYPE OF MINERAL OR A SMALL RANGE OF HARDNESS OF THE MINERALS IN THE AGGREGATE. A RANGE OF 50 TO 70 PERCENT HARD MINERALS IS ESTIMATED TO BE THE OPTIMUM FOR THE AGGREGATES INCLUDED IN THIS STUDY. IT WAS FOUND THAT THE GRAIN SHAPE, SIZE, AND DISTRIBUTION OF THE MINERALS IN AN AGGREGATE HAVE SIGNIFICANT EFFECTS ON SKID RESISTANCE AND THAT THOSE THAT RETAIN OR DEVELOP SURFACE ROUGHNESS UNDER CONDITIONS OF WEAR AND POLISH CONTRIBUTE TO THE MAINTENANCE OF WET PAVEMENT SKID RESISTANCE. /AUTHOR/

• Corporate Authors:

  North Carolina State University, Raleigh

  Raleigh, NC  United States  27695

  North Carolina State Highway and Public Works Commission

  P.O. Box 25201, 1 South Wilmington Street
  Raleigh, NC  United States  27611

  Federal Highway Administration

  1200 New Jersey Avenue, SE
  Washington, DC  United States  20590
• Authors:
  • Mullen, W G
  • Dahir, S H
• Publication Date: 1970-6

Subject/Index Terms

• TRT Terms: Aggregates; Artificial aggregates; Bituminous aggregates; Gneiss; Granite; Gravel; Limestone; Limestone aggregates; Pavement performance; Pavements; Polished aggregates; Rocks; Sandstones; Skid resistance; Slate; Surface course (Pavements); Texture; Wear; Wet weather
• Uncontrolled Terms: Crushed gravel; Diabase; Wet pavements
• Old TRIS Terms: Gneisses
• Subject Areas: Geotechnology; Highways; Pavements;

Filing Info

• Accession Number: 00217492
• Record Type: Publication
• Source Agency: Federal Highway Administration
• Report/Paper Numbers: 69-1
• Files: TRIS, USDOT
• Created Date: Jan 11 1971 12:00AM