Tack Coat Performance and Materials Study

Tack coats provide a bond between asphalt layers so they can act monolithically as one pavement section. Studies have shown that pavement layers that are not fully bonded fail significantly earlier than fully bonded sections. Conversely, application of too much tack material can result in flushing of the new mat or slippage failures. Currently the Ohio Department of Transportation (ODOT) typically specifies SS-1H, rubberized tack or Trackless Tack as the tack coat for paving layers. Application rates are typically between 0.04 to 0.075 gallons of emulsion per square yard. Some limited information tends to show that higher rates of tack may have delayed longitudinal cracking in pavements. Even when tack is properly placed, projects have significant issues with tack being picked up by construction traffic prior to paving. The Department has seen a need for specification of a new Trackless Tack product due to construction issues that arise with other tack coat materials on certain projects. While the benefits during placement of Trackless Tack can be immediately noted, the premium cost and unknown long term performance of the material has limited its use. A study to analyze the pavement performance of different tack materials, application methods, and spray rates is needed. This would allow better decisions about the value of more costly tack materials and the rates at which they should be applied. The goal of the Department for this research is to evaluate the current practice as well as new equipment and application rates with regard to tack coat.

Language

  • English

Project

  • Status: Completed
  • Funding: $296700.00
  • Contract Numbers:

    26923

    135097

  • Sponsor Organizations:

    Federal Highway Administration, Ohio Division

    200 North High Street
    Room 328
    Columbus, OH  United States  43215
  • Project Managers:

    Landefeld, Craig

  • Performing Organizations:

    Texas Transportation Institute

    Texas A&M University System
    3135 TAMU
    College Station, TX  United States  77843-3135
  • Principal Investigators:

    Wilson, Bryan

  • Start Date: 20150217
  • Expected Completion Date: 20170717
  • Actual Completion Date: 20170717
  • Source Data: RiP Project 39083

Subject/Index Terms

Filing Info

  • Accession Number: 01553707
  • Record Type: Research project
  • Source Agency: Ohio Department of Transportation
  • Contract Numbers: 26923, 135097
  • Files: RiP, STATEDOT
  • Created Date: Feb 20 2015 1:00AM