Microbially Induced Calcite Precipitation(MICP)technology can be used to solidify and stabilize heavy metal contaminated soil.This paper mainly studies the strength and chemical stability of MICP-solidified lead-con-taminated soils under freeze-thaw cycles through unconfined compressive strength,ion leaching,and microscopic tests,and reveals its microscopic mechanism.The results show that with the increase in lead ion concentration,the unconfined compressive strength of the soil increases first and then decreases,and the lead ion leaching concentra-tion increases.With the increase in freeze-thaw cycles,the strength of the soil decreases and tends to be stable,and the lead ion leaching concentration increases.After the freeze-thaw cycle,the main mineral components of so-lidified soil do not change;the number of small pores in the soil increases,and the number of large pores remains basically unchanged.Freeze-thaw cycles damage the calcium carbonate cementation and lead ion precipitation struc-ture of solidified soil,resulting in the deterioration of soil properties.
关键词
重金属污染土/微生物诱导碳酸钙沉淀(MICP)/冻融循环/强度及浸出特性/劣化机理
Key words
Heavy metal contaminated soil/Microbially Induced Calcite Precipitation(MICP)/Freeze-thaw cy-cle/Strength and leaching characteristics/Deterioration mechanism
维普
万方数据