Extending supplementary cementitious material resources: Reclaimed and remediated fly ash and natural pozzolans

The concrete industry is under increasing pressure to reduce greenhouse gas emissions and energy use in portland cement manufacturing. While there are several possible ways to address this challenge, an immediate solution is to minimize the amount of portland cement used by partially substituting other materials to make concrete binders. Typical supplementary cementitious materials (SCMs) used in concrete are byproducts of other industries, such as fly ash from coal burning power production. However, in some regions, changes in the supply-demand chain for SCM5 is limiting the ability of the concrete industry to fully utilize these traditional, byproduct SCMs in concrete. This paper addresses current research on avenues for extending SCM resources, particularly in the context of fly ash shortages in the US, including concrete-grade reclaimed fly ash and natural pozzolans. (C) 2017 Elsevier Ltd. All rights reserved.