NEBRASKA EXPERIMENTAL ASPHALTIC CONCRETE RESURFACING PROJECT F-171/12/, PART III

THE RESULTS ARE PRESENTED OF TESTS AND DISCUSSION OF THE DENSITY STUDY MADE ON THE EXPERIMENTAL RESURFACING PROJECT. ONE OBJECTIVE OF THE EXPERIMENT WAS TO DETERMINE THE EFFECTIVENESS OF VARIOUS ROLLER COMBINATIONS AND THE AMOUNT OF ROLLING NEEDED TO ACQUIRE A SPECIFIED DENSITY. THIS OBJECTIVE WAS NOT REALIZED-BUT OTHER INFORMATION WAS GATHERED THAT MAY BE SIGNIFICANT IN A PRACTICAL SENSE. IT WAS FOUND THAT THE DENSITY OF A NEWLY-COMPACTED ASPHALTIC CONCRETE PAVEMENT IS EXTREMELY VARIABLE, AND THAT SEVERAL SAMPLES, SELECTED ON A RANDOM BASIS, MUST BE TAKEN TO BE TRULY REPRESENTATIVE OF THE PAVING SECTION. IT WAS ALSO FOUND THAT NO ROLLER, COMBINATION OF ROLLERS OR ROLLING PROCEDURES PRODUCED A UNIFORM DENSITY THAT COULD NOT BE SIGNIFICANTLY INCREASED BY TRAFFIC. NO ROLLER OR COMBINATION OF ROLLERS SHOWED EVIDENCE OF ANY MARKED SUPERIORITY IN THIS STUDY. THIS STUDY DEMONSTRATED THAT TRAFFIC WILL INCREASE THE DENSITY OF THE SURFACE TO ALMOST ITS ULTIMATE DENSITY WITHIN A FEW WEEKS AFTER CONSTRUCTION IN HOT WEATHER. THE AVERAGE DENSITY OF ALL TEST SECTIONS WAS 93.4 PERCENT OF MARSHALL DENSITY IMMEDIATELY AFTER CONSTRUCTION, 97.9 PERCENT WITHIN 3 MONTHS AND 98.6 PERCENT AFTER SEVEN YEARS. THE DATA INDICATES THAT MIXTURES WITH HIGH PERCENTAGES OF AIR VOIDS COMPACT TO MARSHALL DENSITY MORE EASILY THAN MIXTURES WITH LOW PERCENTAGES OF AIR VOIDS. CONSEQUENTLY, COMPLIANCE WITH A SPECIFICATION BASED ON PERCENT OF MARSHALL DENSITY WOULD BECOME EASIER AS THE PERCENTAGE OF AIR VOIDS INCREASED IN THE PAVING MIXTURE. NO CORRELATION WAS FOUND WITH INITIAL DENSITY OF THE TEST SECTIONS AND THE AMOUNT OF RUTTING EXPERIENCED DURING THE FIRST TWO YEARS THE PAVEMENT WAS IN SERVICE. TO DATE, THE DEGREE OF RUTTING IS NEGLIGIBLE IN ALL SECTIONS. /BPR/

  • Supplemental Notes:
    • Hpr-1(7), BPR ITEM 4, 63-10C
  • Corporate Authors:

    Nebraska Department of Roads

    Materials and Tests Division, P.O. Box 94759
    Lincoln, NE  USA  68509
  • Publication Date: 1969-1

Subject/Index Terms

Filing Info

  • Accession Number: 00214492
  • Record Type: Publication
  • Source Agency: Bureau of Public Roads /US
  • Files: TRIS, STATEDOT
  • Created Date: Oct 28 1994 12:00AM