岩土工程学报2026，Vol.48Issue(1)：15-23,9.DOI:10.11779/CJGE20240795
固碳轻质土制备方法与物理力学性能研究
Research on preparation method and physical-mechanical properties of carbon sequestration lightweight soil
摘要
Abstract
To reduce carbon emissions and explore carbon dioxide(CO2)utilization technologies in geotechnical engineering,this study proposes a novel method for preparing carbon sequestration lightweight soil(C-LS)based on the magnesium oxide(MgO)carbonation mechanism.A mixture of MgO and waste soil is used as a binder instead of cement and CO2 instead of air for foaming.By mixing MgO,silty clay,water and CO2 foam in specific proportions,C-LS with a density of less than 1 g/cm3 is formed.Through unconfined compressive strength tests,scanning electron microscopy(SEM)and thermogravimetric analysis(TGA),the effects of MgO proportions,designed wet densities,water-to-solid ratios and carbonation curing conditions on the fluidity,setting time,dry density,strength,carbonation products and carbon sequestration capacity of C-LS are studied.The results show that with the increase of MgO proportion and wet density,the fluidity and setting time of C-LS decrease,while the strength and carbon sequestration efficiency improve.The optimal mix proportion of C-LS is determined,ensuring that under ambient conditions,its 28-day strength meets the requirements for highway embankment filling and other backfill applications.Under accelerated carbonation conditions,the strength of C-LS can be further improved.Based on the intrinsic relationship between the strength of C-LS,the amount of carbonation product,and the carbon sequestration rate,the study reveals the strength formation mechanism of C-LS and proposes a microscopic model.The C-LS technology can significantly consume CO2 and engineering waste soil,providing a novel technical approach for CO2 sequestration in geotechnical engineering.关键词
C-LS/MgO/二氧化碳泡沫/制备方法/物理力学特性Key words
C-LS/MgO/CO2 foam/preparation method/physical and mechanical properties分类
建筑与水利引用本文复制引用
LIU Songyu,ZHANG Xiang,CAI Guanghua,YUAN Zhenyang,AN Jingfeng,CHEN Guangwei..固碳轻质土制备方法与物理力学性能研究[J].岩土工程学报,2026,48(1):15-23,9.基金项目
国家自然科学基金面上项目(42277146) （42277146）
江苏省研究生科研创新计划(KYCX23_0287)This study was supported by the National Natural Science Foundation of China(Grant No.42277146)and the Postgraduate Research&Practice Innovation Program of Jiangsu Province(Grant No.KYCX23_0287). （KYCX23_0287）
