The Use of Mt. Mazama Volcanic Ash as Natural Pozzolans for Sustainable Soil and Unpaved Road Improvement

Natural pozzolans can be a replacement for portland cement in many applications. Some natural pozzolans are byproducts of industrial processes. Other natural pozzolans, such as volcanic ash, occur naturally. This study determined the suitability of Mt. Mazama volcanic ash as a natural pozzolan and explored innovative uses of the material for roadway improvement. Requirements of natural pozzolans are specified in ASTM C618 – coal fly ash and raw or calcined natural pozzolan for use in concrete. This study concluded that volcanic ash from Mt. Mazama meets chemical requirements of a natural pozzolan. In its unprocessed, natural form, Mt. Mazama volcanic ash does not meet fineness, moisture or strength requirements as a natural pozzolan. An innovative study of the strength of mortar cubes created with increasing replacement of portland cement with Mt. Mazama volcanic ash showed that decreases in strength occur with increased percentage replacements. When the Mt. Mazama volcanic ash is crushed and passed through a No. 200 sieve, this decrease in strength is less than unprocessed material. Slurry mixes of Mt. Mazama volcanic ash, lime and portland cement applied to gravel materials bound material to a greater percentage, and reduced potentially airborne particulates to a greater degree than using portland cement slurry alone. A sustainability analysis concluded that any replacement of portland cement with volcanic ash reduces embodied energy and carbon dioxide emissions

Mount Mazama Ash Offers Sustainable Solution for ADA Accessibility on Unpaved Trails

National Institute for Transportation and Communities (NITC) researcher Matthew Sleep of Oregon Tech investigated whether Mazama ash could be used in place of portland cement, as a natural pozzolan. Results indicate that it can—and unpaved trail surfaces made with Mazama ash are actually firmer and more durable than those made with portland cement alone. Such trails can provide a reliable surface for wheeled mobility devices

The Use of Mt. Mazama Volcanic Ash as Natural Pozzolans for Sustainable Soil and Unpaved Road Improvement

Natural pozzolans can be a replacement for portland cement in many applications. Some natural pozzolans are byproducts of industrial processes. Other natural pozzolans, such as volcanic ash, occur naturally. This study determined the suitability of Mt. Mazama volcanic ash as a natural pozzolan and explored innovative uses of the material for roadway improvement. Requirements of natural pozzolans are specified in ASTM C618 – coal fly ash and raw or calcined natural pozzolan for use in concrete. This study concluded that volcanic ash from Mt. Mazama meets chemical requirements of a natural pozzolan. In its unprocessed, natural form, Mt. Mazama volcanic ash does not meet fineness, moisture or strength requirements as a natural pozzolan. An innovative study of the strength of mortar cubes created with increasing replacement of portland cement with Mt. Mazama volcanic ash showed that decreases in strength occur with increased percentage replacements. When the Mt. Mazama volcanic ash is crushed and passed through a No. 200 sieve, this decrease in strength is less than unprocessed material. Slurry mixes of Mt. Mazama volcanic ash, lime and portland cement applied to gravel materials bound material to a greater percentage, and reduced potentially airborne particulates to a greater degree than using portland cement slurry alone. A sustainability analysis concluded that any replacement of portland cement with volcanic ash reduces embodied energy and carbon dioxide emissions

Applying a Mt. Mazama Volcanic Ash Treatment as a Trail Accessibility Improvement

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

Webinar: Natural Pozzolans in the Pacific Northwest and their Beneficial Uses

The eruption of Mt. Mazama approximately 7,700 years ago created what is now known as Crater Lake. This eruption blanketed the Pacific Northwest with volcanic ash. This volcanic ash has been collected from several locations in Southern Oregon near the Oregon Institute of Technology campus. This volcanic ash has been tested and shown to have properties beneficial of a natural pozzolan. This seminar will present the results of a significant laboratory program to determine the natural pozzolanic capabilities of Mt. Mazama volcanic ash. In addition, information will be presented on a field application using the material to create ADA accessible trail surfaces.https://pdxscholar.library.pdx.edu/trec_webinar/1050/thumbnail.jp

Making Sustainable Roadways from 7,000 Year-old Volcanic Ash

Volcanic ash from Mt. Mazama, prevalent in Southern Oregon, could be used as a natural pozzolan for unpaved roadway improvements. Sustainability benefits would include reduced carbon emissions

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. Naturally occurring, volcanic ash from the eruption of Mt. Mazama is a natural pozzolan. This study examined using this natural pozzolan, in addition to other materials, as a naturally occurring binder. This binder was applied to existing and newly created compacted aggregate trails in the laboratory and the field to determine the benefit as a stabilizer. ADA accessibility tools such as the rotational penetrometer were 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. This study outlines the long-term benefits of using naturally occurring, volcanic ash as a binder applied topically to unpaved trails and discusses the expected increases to firmness and stability

Extensive identification of genes involved in congenital and structural heart disorders and cardiomyopathy

Clinical presentation of congenital heart disease is heterogeneous, making identification of the disease-causing genes and their genetic pathways and mechanisms of action challenging. By using in vivo electrocardiography, transthoracic echocardiography and microcomputed tomography imaging to screen 3,894 single-gene-null mouse lines for structural and functional cardiac abnormalities, here we identify 705 lines with cardiac arrhythmia, myocardial hypertrophy and/or ventricular dilation. Among these 705 genes, 486 have not been previously associated with cardiac dysfunction in humans, and some of them represent variants of unknown relevance (VUR). Mice with mutations in Casz1, Dnajc18, Pde4dip, Rnf38 or Tmem161b genes show developmental cardiac structural abnormalities, with their human orthologs being categorized as VUR. Using UK Biobank data, we validate the importance of the DNAJC18 gene for cardiac homeostasis by showing that its loss of function is associated with altered left ventricular systolic function. Our results identify hundreds of previously unappreciated genes with potential function in congenital heart disease and suggest causal function of five VUR in congenital heart disease