Thematic Evolution and Trends in the Research Field of Concrete and CO2 Interaction: Scientific Mapping Using SciMAT

Abstract

The cement and concrete sector accounts for 5%–10% of global anthropogenic carbon dioxide (CO2) emissions, yet a systematic analysis of thematic evolution and quantitative trends in the research field of concrete and CO2 interaction is lacking, hindering evidence-based low-carbon technology selection. This study employed the scientific mapping tool SciMAT to dynamically analyze 4937 relevant publications from the Web of Science (WOS) database from 1994 to 2023. Following data cleaning that generated 661 keyword clusters and split into three periods (1994–2011, 2012−2017, and 2018–2023) defined by publication inflection points. Co-word analysis, strategic maps, and inclusion-index-based evolution modeling were used to trace thematic birth, growth, decline, and merger. Results reveal five primary evolution directions and 13 statistically significant evolution pathways: concrete composition, concrete performance, concrete carbonation, CO2 emissions, and life cycle assessment (LCA). Keyword analysis shows a 218% growth in research scope over 30 years, with 277 new keywords emerging in the most recent period (2018–2023) compared to only 34 disappearing. Thematic evolution highlights a paradigm shift from passive carbonation studies to active CO2 utilization, exemplified by emerging topics such as CO2 curing and recycled aggregate (RCA) concrete. Based on LCA, three carbon reduction pathways are identified: (a) In the cradle-to-gate phase, reducing emissions in raw material production and manufacturing (up to 40%–60% via supplementary cementitious materials [SCMs]). (b) In the cradle-to-grave phase, enhancing durability to extend service life. (c) Recycling concrete waste with CO2 treatment to achieve “cradle-to-cradle” sustainability. These findings provide a theoretical foundation and strategic guidance for advancing low-carbon concrete technologies and policy-making.