Performance evaluation and specification of trackless tack.

Details

• Creators:
  Wilson, Bryan ; Seo, Ah Young ; Sakhaeifar, Maryam
• Corporate Creators:
  Texas A&M Transportation Institute
• Corporate Contributors:
  Texas. Dept. of Transportation. Research and Technology Implementation Office
• Subject/TRT Terms:
  • Tack coats
  • Bond strength (Materials)
  • Rheology
  • Shear tests
  • Test sections
  • Pavement performance
  • Trackless tack coat
  • tracking resistance
  • cracking resistance
  • bond energy
  More +
• Publication/ Report Number:
  FHWA/TX-16/0-6814-1
• Resource Type:
  Tech Report
• Geographical Coverage:
  United States ; Texas
• Corporate Publisher:
  Texas A&M Transportation Institute
• Abstract:
  Several trackless tack products have come to market in Texas; however, there are currently no specifications to ; ensure the products have trackless properties and adequate bond strength. The objectives of this project were to ; (1) evaluate the tracking resistance of different trackless tacks, (2) evaluate bond strength and other construction ; parameters of different trackless tacks, (3) construct test sections in the field to evaluate performance, and ; (4) develop test procedures and specifications for trackless tack. ; For tracking resistance, a track-free time test and a dynamic shear rheometer (DSR) tackiness test both ; distinguished between trackless tack and conventional tack. The DSR test further distinguished among stiffresidue ; and soft-residue trackless tacks. For bond strength of laboratory samples, all samples had acceptable ; bonding, but stiff-residue trackless tack had the highest bond energy, followed by soft-residue trackless tack, ; conventional tack, and then no tack. Higher ambient and hot mix asphalt (HMA) compaction temperatures ; improved bonding. Bonded trackless tack samples were resistant to fatigue cracking and cold temperature ; delamination. Bond strengths from field samples were considerably lower (15–95 psi) than for lab-molded ; samples (100–200 psi) and varied among different overlay projects. This was likely due to different project ; conditions (e.g., pavement surfaces, HMA overlay designs, compaction temperatures). In most cases tack rate ; did not affect the bond strength. ; The researchers recommend adopting the DSR tackiness test and track-free time test to qualify trackless tack ; materials. The researchers also recommend adopting the shear bond strength test. Draft test methods and a ; trackless tack material specification are provided.
  More +
• Format:
  PDF
• Funding:
  Project 0-6814
• Download URL:
  https://rosap.ntl.bts.gov/view/dot/31505/dot_31505_DS1.pdf
• File Type:
  [PDF - 3.32 MB]
• Collection(s):
  US Transportation Collection
• Main Document Checksum:
  urn:sha256:cf90721d274dd24726df4f5e76e36e3c36b3d25bfcb5ddf2cfcdb2237bddc8ec