Seal Coat Quality: Does Low Cost Mean Low Quality?

Recently the Texas Department of Transportation (TxDOT) administration has provided direction on the types of seal coat material that can be used on a particular facility based on traffic volumes. The more expensive modified binders are reserved for use on higher volume facilities while the very low volume facilities must be sealed with unmodified binders. Given the cost-cutting needs the department faces, this guidance is justified. However, it is just as important (economically) to get the maximum life out of a seal coat. For example, on a very low volume, rural road, a Grade 3 aggregate placed with a polymer modified asphalt (though a more expensive seal coat) may provide a surface that needs no maintenance for 12+ years. The objective of this study is to evaluate the performance of seal coats and materials used statewide and develop guidelines based on cost and performance data regarding what materials should be used and where. To accomplish this goal, districts will be surveyed to understand their experience with the performance and cost of different types of seal coat materials and also to identify sections for further evaluation. Seal coats from the 2011 and 2012 season will be evaluated as well as seal coats from recent research projects. Test sections will be constructed in the four environmental regions to provide a direct performance comparison of different types of seal coat materials. And finally, seal coats will be fabricated in the laboratory and tested to determine the wear resistance of different types of aggregates and the adhesive capabilities of different binders.

Language

  • English

Project

  • Status: Completed
  • Funding: $103431.00
  • Contract Numbers:

    0-6747

    DTRT12-G-UTC06

  • Sponsor Organizations:

    Texas Department of Transportation

    125 E. 11th Street
    Austin, TX  United States  78701-2483
  • Performing Organizations:

    Texas A&M Transportation Institute, College Station

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

    Estakhri, Cindy

  • Start Date: 20120901
  • Expected Completion Date: 0
  • Actual Completion Date: 20140831
  • Source Data: RiP Project 33817

Subject/Index Terms

Filing Info

  • Accession Number: 01568895
  • Record Type: Research project
  • Source Agency: Texas Department of Transportation
  • Contract Numbers: 0-6747, DTRT12-G-UTC06
  • Files: UTC, RiP, STATEDOT
  • Created Date: Jun 30 2015 1:02AM