Portland cement concrete, the most used manufactured material in the world, is a significant contributor to anthropogenic carbon dioxide (CO 2 ) emissions. While strategies such as point-source CO 2 capture, renewable fuels, alternative cements, and supplementary cementitious materials can yield substantial reductions in cement-related CO 2 emissions, emerging biocement technologies based on the mechanisms of microbial biomineralization have the potential to radically transform the industry. In this work, we present a review and meta-analysis of the field of biomineralized building materials and their potential to improve the sustainability and durability of civil infrastructure. First, we review the mechanisms of microbial biomineralization, which underpin our discussion of current and emerging biomineralized material technologies and their applications within the construction industry. We conclude by highlighting the technical, economic, and environmental challenges that must be addressed before new, innovative biomineralized material technologies can scale beyond the laboratory.
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Biomineralization in cement and concrete research
Biomineralization refers to the biological processes through which living organisms produce minerals. In recent years, biomineralizing microorganisms have been used to stabilize soil or to impart a self-healing or self-sealing mechanism to damaged cement and concrete materials. However, applications of biominerals in cement and concrete research can extend far beyond these applications. This article focuses on the biomineralization of calcium carbonate (CaCO3) and silicon dioxide (SiO2) and their past, present, and future potential applications in cement and concrete research. First, we review the mechanisms of CaCO3 and SiO2 biomineralization and the micro- and macroorganisms involved in their production. Second, we showcase the wide array of biomineral architectures, with an explicit focus on CaCO3 polymorphs and SiO2 morphologies found in nature. Third, we briefly summarize previous applications of CaCO3 and SiO2 biomineralization in cement and concrete research. Finally, we discuss emerging applications of biominerals in cement and concrete research, including mineral admixtures or raw meal for portland cement production, as well as other applications that extend beyond self-healing.
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- Award ID(s):
- 1943554
- PAR ID:
- 10537782
- Publisher / Repository:
- RILEM Technical Letters
- Date Published:
- Journal Name:
- RILEM Technical Letters
- Volume:
- 8
- ISSN:
- 2518-0231
- Page Range / eLocation ID:
- 113 to 124
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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