ADA Accessible Trail Improvement with Naturally Occurring, Sustainable Materials

The Americans with Disabilities Act (ADA) provides specific guidelines and requirements that must be met in terms of accessibility. However, in the case of unpaved trails, the requirements are less defined. An ADA trail must be firm, stable and slip resistant. Some compacted aggregate material may meet this definition, but degrade over time and can no longer be ADA compliant. The benefits of using unpaved surfaces for ADA trails include fit to the natural environment, cost, sustainability and environmental benefits such as increased permeability. If an unpaved surface can be improved with the use of an additive, more could be used as ADA accessible trails. A recent study used several different binding materials to improve unpaved ADA accessible trails. However, this study used polymer materials that are costly. Environmentally these materials introduce chemicals that may not be natural to the environment, and unsustainable due to their production. A study currently being conducted with a National Institute for Transportation and Communities (NITC) Small Starts Grant uses naturally occurring, volcanic ash from the eruption of Mt. Mazama as a natural pozzolan. The proposed new study will determine the least amount of portland cement or lime that can be used with this natural pozzolan to create an aggregate binder. This binder will then be applied to existing and newly created compacted aggregate trails in the local community to determine the benefit as a stabilizer and its projected design life. ADA accessibility tools such as the rotational penetrometer will be used to determine if the surface is improved to a firm and stable surface. By determining a low cost, sustainable solution for improvement of ADA accessible trails, more people will have access and connectivity will increase in our community. It is anticipated that this study will provide direct guidance on the composition of a natural pozzolan slurry mix and application methodology to create ADA accessible trails.


  • English


  • Status: Active
  • Contract Numbers:

    NITC 1131

  • Sponsor Organizations:

    Office of the Assistant Secretary for Research and Technology

    University Transportation Centers Program
    Department of Transportation
    Washington, DC  United States  20590

    Oregon Institute of Technology

    3201 Campus Drive
    Klamath Falls, OR  United States  97601
  • Managing Organizations:

    TREC at Portland State University

    1900 SW Fourth Ave, Suite 175
    P.O. Box 751
    Portland, Oregon  United States  97201
  • Project Managers:

    Hagedorn, Hau

  • Performing Organizations:

    Oregon Institute of Technology

    3201 Campus Drive
    Klamath Falls, OR  United States  97601
  • Principal Investigators:

    Sleep, Matthew

  • Start Date: 20170901
  • Expected Completion Date: 20181231
  • Actual Completion Date: 0
  • USDOT Program: University Transportation Centers Program

Subject/Index Terms

Filing Info

  • Accession Number: 01641390
  • Record Type: Research project
  • Source Agency: National Institute for Transportation and Communities
  • Contract Numbers: NITC 1131
  • Files: UTC, RiP
  • Created Date: Jul 21 2017 2:33PM