Understanding the Impact of Fly Ash Particle Size on Reactivity and Strength Development.pdf

Mahmod Yahya, The Ohio State University
Lisa Burris, The Ohio State University

Description

Understanding the Impact of Fly Ash Particle Size on Reactivity and Strength Development Authors Mr. Mahmod Yahya - United States - The Ohio State University Dr. Lisa Burris - United States - The Ohio State University Abstract In the quest for sustainable and efficient construction materials, the role of industrial by-products like fly ash in concrete enhancement has garnered substantial attention. With decreasing coal power production, supplies of virgin ash are declining, and harvested ashes are being increasingly utilized. But harvested ash sources often exceed ASTM C618 fineness limits, having greater quantities of coarse materials, and so currently require significant sieving or milling. This study presents an analysis of the effects of fly ash particle size on the reactivity of the fly ash and the properties of cement mortar utilizing those sources. The research split three harvested fly ash sources into five size fractions through sieving and explored the effects of the materials in cementitious mixtures by substituting portland limestone cement with 20% fly ash. Compressive strengths were tested at 1, 3, 7, 28, 56, and 90 days and thermogravimetric analysis (TGA), quantitative x-ray diffraction (XRD), particle size distribution (PSD), and the R3 test were employed to evaluate the mortar's chemical and physical properties. Preliminary findings will elucidate the correlation between fly ash fineness and the resultant cementitious mixture performance. These results are expected to inform and potentially recalibrate current specification limits and minimize processing required to utilize harvested materials as supplementary cementitious materials in concrete mixes, thereby facilitating the development of more sustainable, durable, and high-performance construction materials.

 
May 14th, 3:30 PM May 14th, 5:00 PM

Understanding the Impact of Fly Ash Particle Size on Reactivity and Strength Development.pdf

Grand Rapids, Michigan

Understanding the Impact of Fly Ash Particle Size on Reactivity and Strength Development Authors Mr. Mahmod Yahya - United States - The Ohio State University Dr. Lisa Burris - United States - The Ohio State University Abstract In the quest for sustainable and efficient construction materials, the role of industrial by-products like fly ash in concrete enhancement has garnered substantial attention. With decreasing coal power production, supplies of virgin ash are declining, and harvested ashes are being increasingly utilized. But harvested ash sources often exceed ASTM C618 fineness limits, having greater quantities of coarse materials, and so currently require significant sieving or milling. This study presents an analysis of the effects of fly ash particle size on the reactivity of the fly ash and the properties of cement mortar utilizing those sources. The research split three harvested fly ash sources into five size fractions through sieving and explored the effects of the materials in cementitious mixtures by substituting portland limestone cement with 20% fly ash. Compressive strengths were tested at 1, 3, 7, 28, 56, and 90 days and thermogravimetric analysis (TGA), quantitative x-ray diffraction (XRD), particle size distribution (PSD), and the R3 test were employed to evaluate the mortar's chemical and physical properties. Preliminary findings will elucidate the correlation between fly ash fineness and the resultant cementitious mixture performance. These results are expected to inform and potentially recalibrate current specification limits and minimize processing required to utilize harvested materials as supplementary cementitious materials in concrete mixes, thereby facilitating the development of more sustainable, durable, and high-performance construction materials.