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Volcanic ash -- Oregon, Sustainable design, Landscape architecture for people with disabilities, Concrete construction, Sustainable construction, Concrete -- Environmental aspects


A procedure has been developed for implementing a topically applied Mt. Mazama volcanic ash trail surface amendment for improving trail firmness and stability. This project involved implementation of previously conducted Mt. Mazama volcanic research by applying a Mazama Ash and Portland Cement solution over a 0.2-mile section of the Geo Trail at the Oregon Institute of Technology Klamath Falls campus. Testing was performed to verify ideal Ash-to-Cement-to-Water ratios. A procedure was developed and applied for batching and mixing the dry materials on-site, spreading and integrating the dry material with the existing trail surface, and wetting and compacting the surface. After the pilot application, visual inconsistencies were observed in the treated trail surface. Firmness and stability were measured at different locations along the treated trail surface and on the untreated surface with a rotational penetrometer apparatus. Roughness was quantified using a modified Wheelchair Pathway Roughness Index at different locations along the treated rail surface and on the untreated surface. At each of the testing locations on the treated surface, stability was shown to have improved, firmness was relatively consistent, and the ability to roll an occupied wheelchair without rutting was markedly improved.


This is a final report, NITC-TT-1529, from the National Institute for Transportation and Communities (NITC) program of TREC at Portland State University, and can be found online at

Project brief associated with this report archived here:



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