Evaluation of Otta Seal Surfacing for Low-Volume Roads in Iowa - Phase II

This proposed phase II research is a follow-up investigation of the recently completed TR-674 (IHRB-13-08), entitled, “Evaluation of Otta Seal Surfacing for Low-volume Roads in Iowa”. The primary objectives of this proposed phase II research are listed below:  To establish the recommended specifications including quality control/quality assurance (QC/QA) procedures for Iowa Otta seal construction projects through two concurrent research studies: (1) comprehensive laboratory evaluation & characterization and (2) field implementation projects Specific objectives established to achieve this primary objective include the following:  Evaluate various local aggregate types in Iowa suitable for Otta seal construction  Develop rational or engineered approach for determining the optimum application rates for asphalt binder and aggregate systems in Otta seal applications  Identify road surface/base preparation requirements before Otta seal application  Develop minimum requirements for aggregate layer thickness (with CBR ranges for subgrade strength) to establish Otta Seal selection for an unpaved road  Develop minimum requirements (i.e., PCI or SN ranges) to identify candidates for Otta Seal placement on existing HMA pavements  Identify test and control procedures for checking and calibrating actual field application rates of asphalt binder and aggregate  Evaluate rolling operations (e.g., number of passes) for achieving appropriate field compaction  Identify test procedures for determining curing times on Otta seals and recommend the optimum curing time between 1st and 2nd layer for double Otta seal construction  Evaluate the feasibility of using recycled materials (RAP or slag) as an alternative to virgin aggregate in Otta seal  Evaluate if Otta seal layers could be used as one of the holding strategy options for Iowa county roads


    • English


    • Status: Completed
    • Funding: $349,601
    • Contract Numbers:

      Addendum 665


    • Sponsor Organizations:

      Iowa Department of Transportation

      800 Lincoln Way
      Ames, IA  United States  50010
    • Managing Organizations:

      Iowa Department of Transportation

      800 Lincoln Way
      Ames, IA  United States  50010
    • Project Managers:

      Goetz, Vanessa

      Moore, Brian

    • Performing Organizations:

      Iowa State University, Ames

      Institute for Transportation
      2711 South Loop Drive, Suite 4700
      Ames, Iowa  United States  50010-8664
    • Principal Investigators:

      Ceylan, Halil

      Kim, Sunghwan

      Jahren, Charles

      Zhang, Yang

    • Start Date: 20180701
    • Expected Completion Date: 20210630
    • Actual Completion Date: 0

    Subject/Index Terms

    • TRT Terms: Road materials
    • Subject Areas: Construction; Maintenance and Preservation;

    Filing Info

    • Accession Number: 01675172
    • Record Type: Research project
    • Source Agency: Iowa Department of Transportation
    • Contract Numbers: Addendum 665, TR-753
    • Files: RIP, STATEDOT
    • Created Date: Jul 19 2018 12:12PM