Evaluation of tack coating practices for asphalt overlays in Nebraska.

Details

• Creators:
  Amelian, Soroosh ; Kim, Yong-Rak
• Corporate Creators:
  University of Nebraska--Lincoln. Dept. of Civil Engineering
• Corporate Contributors:
  Nebraska. Dept. of Roads
• Subject/TRT Terms:
  Asphalt Pavements Bituminous Overlays Direct Direct Shear Tests Overlays (Pavements) Pavement Performance Performance Ranking Shear Test Shear Tests Asphalt Pavement Tack Coats
• Resource Type:
  Tech Report
• Geographical Coverage:
  Nebraska;United States
• Corporate Publisher:
  Nebraska. Dept. of Roads
• Abstract:
  The strength of the bond between asphalt layers affects the lifespan of pavement structures. It is also a key factor
  
  in preventing major pavement distresses, such as slippage cracking and delamination. This research project
  
  evaluates and compares the effectiveness and performance of different tack coating approaches to ensure the
  
  proper bond strength is achieved in asphalt concrete (AC) interlayers through an experimental study. Various
  
  tack coat materials, including different types of emulsified asphalt and asphalt binders, at multiple application
  
  rates and dilution ratios were investigated. In the first part of this study, laboratory-prepared samples were used
  
  to evaluate the sensitivity and effectiveness of the direct shear testing (DST) method, which was selected for the
  
  characterization of the AC interlayers where different tack coats were treated. Then, emulsified asphalts and
  
  binders were applied to a field test section by varying application rates. The DST was performed under a
  
  monotonic loading condition at three different testing temperatures. Interlayer shear strengths were used to rank
  
  the performance of the tack coats. In addition, cyclic DST was conducted to investigate fatigue behavior of the
  
  interlayers treated with different tack coats. The parameters obtained from the monotonic DST were compared
  
  with the fatigue DST results. In general, the test results showed superior interlayer performance from CFS-1 and
  
  CRS-2P at double application rate (i.e., 0.16 gal/yd2 residual application rate) and CFS-1 at the standard
  
  application rate (i.e., 0.08 gal/yd2 residual application rate). Moreover, CRS-2P provided the shortest breaking
  
  time among all the emulsified tack coats. With regard to the correlation between the monotonic and cyclic DST
  
  results, the maximum shear force showed an acceptable correlation with the fatigue test results, and the interlayer
  
  bond energy, which can also be determined using a monotonic DST, is a good (or better) predictor of the fatiguerelated
  
  shear resistance of the tack coats due to its higher correlation with the fatigue test results.
  
  
• Format:
  PDF
• Funding:
  SPR-P1(16) M039
• Collection(s):
  US Transportation Collection
• Main Document Checksum:
  urn:sha-512:09d6855c19a84e88d71804daae535a2b3ebf0c46941cccfbe1b6bfa80e33af2eea30761001b42baaf2f44469079e2fc22b8a4dfc6ab504b7e38a9145a170a02a
• Download URL:
  https://rosap.ntl.bts.gov/view/dot/32504/dot_32504_DS1.pdf
• File Type:
  [PDF - 8.95 MB ]