Comparative Evaluation of 4-Inch and 6-Inch Diameter Specimens for Testing Large Stone Asphalt Mixes

Details

• Creators:
  Kandhal, Prithvi S. ; Brown, E.R.
• Subject/TRT Terms:
  Aggregates, Rock And Stone Asphalt Mixtures Binder Content Gyratory Testing Machines (GTM) Marshall Mix Design Method Test Procedures
• DOI:
  https://doi.org/10.21949/1404492
• Resource Type:
  Tech Report
• TRIS Online Accession Number:
  00625354
• Corporate Publisher:
  National Center for Asphalt Technology (U.S.)
• NTL Classification:
  NTL-HIGHWAY/ROAD TRANSPORTATION-Materials ; NTL-HIGHWAY/ROAD TRANSPORTATION-Pavement Management and Performance
• Abstract:
  Increased incidence of premature rutting of heavy duty asphalt pavements has
  
  been experienced in recent years. There is a general agreement among most
  
  asphalt paving technologists that the use of large size stone in the binder and
  
  base courses will minimize or eliminate the rutting of heavy duty-pavements.
  
  However, the wide acceptance of the Marshall and Hveem mix design procedures
  
  inhibits the use of large stone mixes because these methods use standard 4-inch
  
  (101.6 mm) diameter specimens and limit the maximum aggregate size to one inch
  
  (25.4 mm).
  
  Modified Marshall equipment and Gyratory Testing Machine (GTM) are now available
  
  for compacting and testing 6-inch (152.4 mm) diameter specimens to accommodate
  
  aggregate up to 2-inch (50.8 mm) maximum size. However, some agencies continue
  
  to use 4-inch diameter specimens for mixes containing 1&1/2inch (38.1 mm)
  
  maximum size aggregate. This study compares the mix properties such as Marshall
  
  stability and flow, indirect tensile strength, and permanent deformation (from
  
  static creep test) obtained on 4-inch and 6-inch (101.6 and 152.4 mm) diameter
  
  specimens. Both Modified Marshall and GTM equipment were used to compact the
  
  specimens of these two sizes. The maximum aggregate size ranged from 1/2 to
  
  l&1/2-inches (12.5 to 38.1 mm).
  
  The test data indicates increased coefficient of variation when testing 4-inch
  
  (101.6 mm) specimens of the mix containing aggregate larger than one inch
  
  (25.4 mm) compared to 6-inch (152.4 mm) specimens. The 6-inch (152.4 mm)
  
  diameter specimens also had lower variability in creep test compared to 4-inch
  
  (101.6 mm) specimens. Laboratory and rationally derived data indicating the
  
  ratios by which stability and flow values increased is also given in the paper.
  
  It has been recommended to use 6-inch (152.4 mm) diameter specimens for large
  
  stone asphalt mixes.
  
  
• Format:
  PDF
• Collection(s):
  US Transportation Collection
• Main Document Checksum:
  urn:sha256:3e4b3863289d6b290ae490db4e644eaf42f429bb0f3d644fa77d5cd2acc4562a
• Download URL:
  https://rosap.ntl.bts.gov/view/dot/13187/dot_13187_DS1.pdf
• File Type:
  [PDF - 136.25 KB ]