CAREER: Taking Sustainable Cements to the Next Level: New Routes to Control and Amplify the Chemical Reactivity of Cementing Phases

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This Faculty Early Career Development (CAREER) project engineers portland cements having enhanced reactivity, so as to substantially enhance efficiencies associated with the use of cement in concrete. Reactivity amplifications are provoked by manipulating: (1) impurity distributions (i.e., guest ions) and (2) thermal processing (e.g., quenching) routes through cement synthesis. These manipulations induce structural imperfections in cement minerals, and thus act to elevate their reactivity. Reactivity is studied across quantum-to-continuum scales using density functional theory and molecular dynamics calculation, by synthesis of pure cement phases and their solid solutions, and by nanoscale measurements of phase dissolution rates. The investigations are organized for calculation and experiment to interact with each other, and guide the discovery of highly reactive cementing phases through detailed considerations of phase chemistry, properties and processing.This research places emphasis on reactivity, to produce concretes using a smaller quantity of highly reactive cement, which are performance-equivalent to concretes produced today using larger quantities of traditional cements. Thus, by reducing the use/wastage of cement in concrete, the outcomes of the work conservatively target global cement (and CO2 emissions) savings of around 15%, i.e., around 500 million tons. This is a translational paradigm in reducing cement use, which will radically alter how sustainability is approached from a materials perspective by the construction industry. The project develops graduated training across levels of scientific maturity, from high-school students to post-doctoral scientists. Diversity and high-school engagement platforms at UCLA are leveraged to provide research opportunities to financially disadvantaged minority candidates, while LA-high-school educators and YouTube and Facebook ventures are engaged to incite interest in, and provide growth opportunities to young scientists.