Innovation alert: Use volcanic ash on trails? Yes!

Research project shows naturally occurring material can improve access for people with disabilitiesWorking with Mazama ash

Trails are transportation, too – a mode a lot of people in Oregon enjoy regularly, in fact. Wouldn’t it be nice if it was easier to create trails that were accessible for people with disabilities?

Dr. Matthew Sleep thought so, and his recently completed research project proved it to be true.

In May, Sleep and his team at the Oregon Institute of Technology in Klamath Falls published the results of their project. They presented those results earlier this year at the bi-annual Northwest Transportation Conference in March.

“Two key pieces led us to this project,” Dr. Sleep explained. “Volcanic ash from the Crater Lake area, when Mt. Mazama erupted 7,700 years ago, and looking for ways to create firm and stable surfaces for trails so they would meet ADA requirements.”

Volcanic ash, it turns out, is a natural pozzolan – or binder. That means in presence of portland cement it makes a better cement, and it can even sometimes act alone.

Another benefit? It’s a binder that’s similar to fly ash, which is a by-product of coal burning, so pozzolan could replace fly ash in some applications – great for the environment.

Back to trails, though, the benefits continue.Field testing volcanic ash

“We created 12 different sections of trail on campus and then applied mixtures with varying amounts of pozzolan, portland cement and water. In addition, we used three commercially available gravel stabilizers. After 70 days of monitoring, the lots treated with Portland cement and volcanic ash continued to show improvement at a higher rate than the commercial stabilizer.”

Not only does the ash improve accessibility, it is less expensive.

“I think at a minimum the volcanic ash has huge implications for any department of transportation,” Sleep said. “Texas DOT has studied ash from as far away as Idaho to replace fly ash. We have now shown this material to be beneficial.”