Future and emerging supplementary cementitious materials

To sustain the decarbonization of the cement industry, identifying new sources of supplementary cementitious materials (SCMs) is crucial. This review paper examines recent scientific literature on the understanding, assessment, and processing of future and emerging SCM resources. Among the SCMs that have generated significant interest are calcined clays, natural pozzolans, reclaimed coal fly ashes, certain biomass ashes, concrete recycling fines, and recycled glass. These SCMs are gaining market access, and their processing and performance have been well-established in local contexts. A growing body of research is considering a much wider array of by-product and waste materials as potential future SCM sources. These materials are often available in high volumes, but they typically require beneficiation processing to enhance their performance and compatibility as SCM. While promising results have been achieved for many materials, future research and development efforts are necessary to better understand their impact on cement and concrete properties and establish or improve the viability of the proposed beneficiation processing. In conclusion, this review highlights the latest developments in testing and specifications that support the uptake of a wider range of SCMs in cement and concrete.