The state of the art of carbonation technology in geotechnical engineering: A comprehensive review

Abstract

The carbonation technology, which is promising in carbon capture and storage, is an emerging soil treatment method adopted in geotechnical engineering and geo-environmental engineering to enhance mechanical properties or mitigate environmental risks. The advantage of utilising CO2 in solving engineering problems shows a large potential for the technology to be widely used to alleviate the greenhouse emission problems; Nevertheless, the changes in soil characteristics, including physical, chemical, mechanical, deformation, and durability characteristics, caused by carbonation are complicated, which brings challenges to possible engineering applications. This paper reviews the recent development of carbonation technology in geotechnical engineering and provides a systematic analysis of the effect of carbonation on soil properties, from the macro behaviours to the micro mechanism. The “double-edged sword” effect of carbonation on the mechanical properties of soils is proposed, together with the micro-scale mechanisms illustrated. A qualitative theoretical model for the prediction of the mechanical strength of carbonated soils is established. The prospective future and important insights of the carbonation technology to be utilized in geotechnical engineering can be concluded from the review, although some potential technical issues, including possible carbonation crack, heavy metal leaching, durability issues, and lack of construction techniques, require further study.