碳化作用对水泥固化/稳定化铅污染土渗透特性的影响

采用人工配制铅污染土的方法制备不同水泥掺量和不同铅浓度的土样,开展碳化前后水泥固化/稳定化铅污染土的渗透试验,并分析试样的宏观渗透系数和微观孔隙结构之间的内在联系。研究结果表明,水泥掺量增加会降低试样的渗透系数;水泥掺量为7.5%时,碳化作用下渗透系数提高;水泥掺量为15%时,碳化作用下渗透系数降低。铅浓度越高,试样的渗透系数越高,而碳化作用又会增大试样的渗透系数。水泥掺量增加会显著降低试样的孔隙率;碳化作用使得试样中孔径小于0.1μm的孔隙增多,大于0.1μm的孔隙减少。

Effects of carbonation on permeability characteristics of cement-stabilized/ solidified lead-contaminated soil

The method for artificially prepared lead-contaminated soil is used to prepare soil samples with different cement contents and lead concentrations. The effects of carbonation on the permeability of cement-solidified/stabilized lead-contaminated soil are studied. The relationship between the pore structures under the microscopic and the coefficient of permeability are compared. The results show that when the cement content is 7.5%, the carbonization increases the coefficient of permeability. When the cement content is 15%, the coefficient of permeability decreases under carbonization. The higher the lead concentration, the higher the coefficient of permeability of the sample, and the carbonization increases the permeability coefficient of the sample. The increase in the cement content significantly reduces the porosity of the sample. The porosity and coefficient of permeability of the sample increase under carbonization. The increase of the cement content significantly reduces the porosity of the sample. The carbonization increases the pore size of the sample with a pore diameter of less than 0.1 μm, and decreases the pore size of more than 0.1 μm.