NaOH污染下水泥土的电阻率变化研究

Study on electrical resistivity of soil-cement polluted by NaOH

通过室内浸泡试验模拟了不同龄期的水泥土试块受不同浓度NaOH溶液的污染,采用电阻率法研究了电阻率与各参数之间的关系。结果表明,水泥土和孔隙水电阻率随溶液浓度增大而减小,随龄期的增大而增大;结构因子随溶液浓度增大而增大,随龄期的增大而减小。然后通过对水泥土无侧限抗压强度试验结果的分析,得到了强度与水泥土电阻率的关系式,它们具有较好的线性相关性。在此基础上推导出预测任意溶液浓度和龄期的水泥土电阻率公式,经对比预测值与实测值,证明它们比较接近,说明公式的准确性较高。研究认为:水泥土的电阻率特性与污染程度和抗压强度密切相关,可以用来反应污染程度和抗压强度。

Through the lab tests on soil-cement blocks polluted by various concentrations of NaOH solution, the relations between electrical resistivity and various parameters were studied. It was indicated that the electrical resistivity and formation factor were closely correlated with solution concentrations and age time. Then a strength equation related with the electrical resistivity of soil-cement was obtained by analyzing the results of unconfined compression strength test. The equation indicated that the unconfined compression strength was in proportion to its electrical resistivity. Finally a forecast formula was set up to indicate the relationship of electrical resistivity with solution concentration and age time. The predicted and measured values were close so that the accuracy of the formula was rather high. A conclusion was drawn that the electrical resistivity of soil-cement was closely related with its pollution degree and unconfined compression strength, so the electrical resistivity might be taken as an effective means to appraise the pollution degree and unconfined compression strength of soil-cement in practical engineering projects.