【摘要】：通過無側限抗壓強度、滲透系數(shù)、浸出濃度以及形態(tài)分布測試,分別考察了不同條件下反復凍融和高溫老化作用對砷污染土壤固化或穩(wěn)定化效果的影響,同時利用掃描電鏡分析了穩(wěn)定化土壤的微觀形貌變化.結果表明,反復凍融和高溫老化處理均會不同程度地削弱固化土壤的抗壓強度,并提高其滲透系數(shù).兩種處理會增加穩(wěn)定化土壤中砷的不穩(wěn)定形態(tài),從而增大其浸出濃度,如反復凍融處理300次后,穩(wěn)定化土壤中砷的不穩(wěn)定形態(tài)增加了19.81%,浸出濃度由115.5μg·L~(-1)增加至151.5μg·L~(-1),80℃高溫老化10 h后,砷的不穩(wěn)定形態(tài)增加了25.1%,浸出濃度增加至164.5μg·L~(-1).反復凍融次數(shù)的增加、老化溫度的升高以及老化時間的延長,均會分別增大對固化/穩(wěn)定化效果的影響.穩(wěn)定化土壤經反復凍融和高溫老化處理后,會發(fā)生不同程度的碎裂,呈現(xiàn)結構松散狀.
[Abstract]:The effects of repeated freezing and thawing and high temperature aging on the solidification and stabilization of arsenic-contaminated soil were investigated by testing the unconfined compressive strength, permeability coefficient, leaching concentration and speciation distribution of arsenic-contaminated soil under different conditions. At the same time, the microstructure of stabilized soil was analyzed by scanning electron microscope (SEM). The results showed that repeated freezing and thawing treatment and high temperature aging treatment could weaken the compressive strength and increase the permeability of solidified soil in varying degrees. The two treatments increase the unstable form of arsenic in the stabilized soil, thus increasing its leaching concentration, such as after 300 times of repeated freezing and thawing, The unstable form of arsenic in stabilized soil increased 19.81, and the leaching concentration increased from 115.5 渭 g / L ~ (-1) to 151.5 渭 g / L ~ (-1). After aging at 80 鈩，

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