含水率与含砂率对软黏土电阻率影响的试验研究

Experimental Study on Influence of Water Content and Sand Content on Resistivity of Soft Clay

软黏土电阻率是电渗固结时的重要参数,直接影响着电渗固结的效率、阴阳极之间的间距设置等。含水率与含砂率是软黏土电阻率最常见的两个影响因素,需深入研究。试验采用改进的Miller Soil Box,测试了20个不同含水率、不同含砂率的软黏土土样的电阻率。依据试验数据结果,分析软黏土含水率对电阻率的影响、软黏土含砂率对电阻率的影响,以及含砂率与含水率对电阻率的交互影响。试验结果表明电渗固结适用于含砂率低且含水率高的软黏土,高含砂率对电渗固结是不利的。遇到高含砂率的软黏土时,不易采用电渗固结。电渗固结时,软黏土中含水率小于20%时,随着含水率的降低,土样的电阻率急剧上升;故将软黏土中的含水率降低到20%左右时,可以作为停止电渗固结的参数之一。

The resistivity of soft clay is an important parameter of electro osmotic consolidation. It directly affects the efficiency of electro osmotic consolidation,the spacing between anode and cathode,and so on. Water content and sand content are the two most common factors affecting the resistivity of soft clay,which need further study. Twenty orthogonal tests were conducted to test the resistivity of soil samples with different water content and sand content by using the improved Miller Soil Box. According to the model test data,the influence of water content and resistivity of soft clay,the influence of sand content and resistivity of soft clay,and the interaction between sand content and water content on resistivity are analyzed. The test results show that electro osmotic consolidation is applicable to soft clay with low sand content and high water content,and high sand content is unfavorable to electro osmotic consolidation. It is difficult to use electroosmotic consolidation when encountering soft clay with high sand content. Electroosmotic consolidation,water content less than 20% in soft clay,the resistivity with decreasing of moisture content of the soil increased sharply,so the water in soft clay ratio decreased to about 20%,can be used as one of the parameters of electroosmotic consolidation stop.