单轴压缩垃圾液污染黄土电阻率特征试验研究

Experiment Study on Resistivity Characteristics of Landfill Leachate Contaminated Loess in Uniaxial Compression Process

为研究不同含水率、垃圾渗滤液浓度的原状污染黄土电阻率与压缩特征之间的关联,人工配置垃圾渗滤液对黄土进行预污染,制备了不同含水率、不同污染液浓度侵扰的黄土试样,并基于Fukue提出的固结仪-电阻率试验原理进行室内试验,分析了不同含水率和渗滤液浓度对电阻率的影响,进一步探讨了各含水率下不同污染试样压缩系数与电阻率特征值之间的定量关系。结果表明:污染液侵入后会导致土体电阻率急剧降低,不同污染浓度试样间电阻率的差值较小;低含水率时电阻率对水分的响应度更高,随含水率升高,响应度开始降低;在0~100 kPa应力下,电阻率出现骤降,当应力增加至100 kPa后,电阻率逐渐稳定;以垃圾渗滤液含水状态为中间变量,进一步拟合了压缩系数与电阻率特征值之间的关系,其呈现出指数递减趋势;最后提出不同孔隙水化学溶液下的利用电阻率特征值评价黄土受垃圾渗滤液污染程度影响的工程分级评价建议。

In order to investigate the relationship between the resistivity and compression coefficient of contaminated loess at different water contents and landfill leachate concentrations,the loess samples were pre-contaminated by artificially leachate.Then laboratory tests were carried on based on the consolidation-resistivity test principle which proposed by Fukue,and the effects of water contents and leachate concentrations on resistivity were analyzed.The quantitative relationship between the compression coefficients and resistivity characteristic values at different pore water state was also analyzed.The results showed that The intrusion of contaminated liquid will lead to a sharp decrease in soil resistivity,and the difference in resistivity between specimens with different contamination concentrations is small;the resistivity response to moisture is higher at low water content,and begins to decrease as the water content increases,Sudden drop in resistivity at 0 to 100 kPa;when the stress increases to 100 kPa,the resistivity gradually stabilizes;the relationship between the compression coefficient and the characteristic value of resistivity is further fitted using the water content state of the waste leachate as an intermediate variable,and it shows an exponentially decreasing trend.Then,an engineering classification suggestion of resistivity characteristic value was proposed to evaluate the effect of contamination loess by landfill leachate.