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

Abstract

13. Type of Report and Period Covered 14. Sponsoring Agency Code 15. Supplementary Notes AbstractThis report investigates the viability of using volcanic ash deposited from the eruption of Mt. Mazama as a natural pozzolan and substitute for the more conventional methods of soil stabilization and unpaved roadway improvement, including dust abatement. Chemical analyses show that Mt. Mazama volcanic ash has similar chemistry to that found in many pozzolanic materials. Standard and modified ASTM strength activity index (SAI) testing was performed on a variety of mixtures containing volcanic ash, hydrated lime, crushed volcanic ash and portland cement at different percentages. A gravel wash sieve test and a slurry mix test were devised in order to determine how the ash could be used to both penetrate into compacted gravel layers and bind material together for the prevention of dust mitigation as defined by the EPA. These new procedures indicate that Mt. Mazama ash can be effective as a supplement to portland cement for binding compacted gravel layers and reducing the dust particulate percentage. Mt. Mazama ash, mixed with highly compressible and organic soil, does not increase unconfined compressive strength. Sustainability studies show that any replacement of portland cement with volcanic ash reduces carbon dioxide emissions and embodied energy.

Volcanic Ash as a Sustainable Binder Material: An Extensive Review

“…With respect to the fineness of the VA particles, the optimal grain size for Class N pozzolans should be ≤75 µm or the particles should be able to pass through a No. 200 sieve [ 11 ]. In accordance with the mechanical properties, the European Standard EN 450 and ASTM C618 specifications describe that the minimum strength activity index (SAI) of mortar samples produced with 25% or 20% of VA material, respectively, should be 75% of the compressive strength achieved by a 100% OPC control sample at 28 days [ 63 ].…”

“…Pozzolanic materials have been used since the Greek and Roman civilizations, which first used them in lime mortars to build such structures as bridges, basilicas, aqueducts, coliseums and temples; the use of these materials also became common at the beginning of the 20th century in the United States [ 10 ]. When pozzolanic materials are used as supplementary cementitious materials with OPC, several properties are improved with respect to 100% OPC [ 11 , 12 ]. For example, in the fresh state, cementitious materials improve the workability, reduce water retention/bleeding and lower the heat of hydration.…”

Characteristics of Kedondong Trass and Bobos Trass as Cement Raw Material, Cirebon, West Java, Indonesia

“…The intrinsic capacity of pozzolans is depend of chemical composition, which is varies greatly in volcanic deposits (Yu et al, 2017). After chemical criteria meets the requirement, most raw materials need to be processed to meets the physical criteria such as fineness, moisture, and strength (Sleep and Masley, 2018). American Standard for Testing Materials (ASTM) C618-94a 1993C618-94a (ASTM, 1993 specifies standard chemical composition of raw and calcined natural pozzolans for use in concrete as shown by Table 1.…”

“…As natural pozzolans, Kedondong and Bobos trass contain 83% -87% silica and alumina originated from intermediate volcanic rocks. In addition to durability aspect, silica and alumina compounds are responsible for reacting with hydroxides to produce calcium silica hydrate (C-S-H).This byproduct of water and cement reaction is a strong binding agent which desired in the mixture (Sleep and Masley, 2018). Generally, the higher SiO2 in natural pozzolans, the better pozzolanic activity (Çavdar and Yetgin, 2007).…”

From Ash to Action: Student-Led Sustainable Trail Resurfacing Using Mt. Mazama Volcanic Ash

“…Mazama erupted approximately 8000 years ago, leaving behind what is now known as Crater Lake in Southern Oregon and a thick layer of volcanic ash across the Pacific Northwest region. Researchers at Oregon Tech had been studying the pozzolanic behaviors of Mazama Ash and its potential as a surface treatment for improving trail firmness and stability [1]. As a locally available material, Mazama Ash has the potential to be more sustainable than alternative cementitious soil stabilizers.…”