Density of Asphalt Concrete - How Much is Needed?

Details

• Creators:
  Brown, E.Ray
• Subject/TRT Terms:
  Asphalt Asphalt Mixtures Cores (Specimens) Deformation Instruments For Measuring Density Nuclear Gages Nuclear Meters Physcial Properties
• DOI:
  https://doi.org/10.21949/1404494
• Resource Type:
  Tech Report
• Geographical Coverage:
  Alabama;United States
• TRIS Online Accession Number:
  00750977
• 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:
  Density is one of the most important parameters in construction of asphalt
  
  mixtures. A mixture that is properly designed and compacted will contain enough
  
  air voids to prevent rutting due to plastic flow but low enough air voids to
  
  prevent permeability of air and water. Since density of an asphalt mixture
  
  varies throughout its life the voids must be low enough initially to prevent
  
  permeability of air and water and high enough after a few years of traffic to
  
  prevent plastic flow.
  
  There are three primary methods of specifying density: percent of control strip,
  
  percent of laboratory density, and percent of theoretical maximum density. All
  
  three methods can be used to obtain satisfactory compaction if used correctly.
  
  The initial in-place air voids must be below approximately eight percent and the
  
  final in-place air voids must be above approximately three percent. The initial
  
  in-place air voids are determined by comparing bulk density to theoretical
  
  maximum density (TMD) and the final in-place air voids are estimated by
  
  comparing bulk density of laboratory compacted sampler to the TMD.
  
  The two methods that have been used to measure bulk density of asphalt mixture
  
  are physical measurements of cores and nuclear gage. The nuclear gage is fast
  
  and non-destructive but is not as accurate as the core method.
  
  
• Format:
  PDF
• Collection(s):
  US Transportation Collection
• Main Document Checksum:
  urn:sha256:9db7b94057582605e40f98cc191639a9e5a5e422ebb4b10fe6732bd8bbc95a52
• Download URL:
  https://rosap.ntl.bts.gov/view/dot/13189/dot_13189_DS1.pdf
• File Type:
  [PDF - 165.94 KB ]