OasisLMS

As the supply of conventional supplementary cementitious materials (SCMs) continues to fall behind concrete industry’s demand, new sources must be identified and evaluated to allow production of high-quality and durable concrete. This course reports on the latest research related to the use of harvested fly ash (HFA) and ground bottom ash (GBA) as concrete SCMs. The presentations will include studies on the chemical and physical characteristics of these ashes, their pozzolanic reactivity, and their performance in concrete in terms of their impact on fresh, mechanical, and durability properties of concrete mixtures. The audience will become familiar with this potentially valuable new SCM source.


The contents of this course include four recorded presentations from the ACI 2023 Spring Convention:
• Making the Case for Including Harvested Coal Ash in ASTM C618 by R Doug Hooton, University of Toronto
• Ash Marketers’ Perspectives on Harvesting and Beneficiation of Coal Ash by Cole Spencer, Eco Material Technologies; Saiprasad Vaidya, Ashcor; Ross Gorman, SEFA
• Use of Fly Ash Co-Mingled with Flue Gas Desulfurization Products as Alternative SCM by Farshad Rajabipour, Pennsylvania State University
• The Effect of Blending Harvested Off-Spec Fly Ash with Ground Glass Fibers on The Mechanical and Durability Behavior of Portland Cememt Concrete by Prasad Rangaraju, Clemson University

1. Compare the properties and performance of harvested fly ash (HFA) and ground bottom ash (GBA) as used in concrete with traditional freshly generated fly ashes.
2. Describe the process of how ground bottom ash and harvested fly ash is found, separated, reclaimed, and processed to be used as a supplementary cementitious material in concrete with similar properties to freshly generated fly ash.
3. Discuss methods for assessing the reactivity of HFA and GBA in blended cements, including effects on set times and hydration rates when blended with portland cement concrete.
4. Explain properties of concrete having blended cements with harvested fly ash and ground-glass fibers and other materials.

Study the materials included in this module. Then, complete and pass the corresponding 10-question quiz with a score of 80% or higher to receive a certificate for 0.2 CEU (2.0 PDH).
Continuing Education Credit: 0.2 CEU (2.0 PDH)
Approved AIA and ICC
Access Period: 30 days