National Concrete Pavement Technology Center

Project description

This project seeks to validate and improve quantification methods and simulation models to better understand CO₂ uptake in concrete pavements during their service life and recycled concrete aggregate at the end-of-life phase. Hydrated cement in concrete has the potential to sequester CO₂ during the use and end-of-life phases through carbonation, a mineralization process where atmospheric CO₂ reacts with alkali products like portlandite to form stable carbonates. Pavement systems have significant potential for carbonation due to their constant exposure to the environment, the use of preservation methods like diamond grinding that repeatedly expose fresh hydrated cement, and the stockpiling of crushed concrete at the end of its life, where the increased surface area can enhance carbonation. However, systematic methods for quantifying and addressing this uptake in transportation systems is lacking. In this work, the research team will use laboratory characterization of carbonation depth, analysis of factors influencing RCA carbonation in stockpiles, and validation of diffusion-based models to better inform consideration of carbon sequestration in concrete. By considering regional climate variations and assessing the impacts of preservation practices, this work aims to inform sustainable pavement management practices.