含水率及孔隙率对黏性土电阻率影响的试验研究——以桂林红黏土、粉质黏土为例

为获得土体电阻率与含水率及孔隙率之间的定量关系，以桂林红黏土、粉质黏土为研究对象，通过更严格的单因素控制试验，在保持其他各因素不变的情况下，探讨两种土体的电阻率随含水率（保持土体类型、孔隙率不变）、孔隙率（保持土体类型、含水率不变）的变化规律，并引入能够综合反映含水率和孔隙率变化的土体体积含水率，探讨电阻率与体积含水率间的确定性关系及经验公式。试验结果表明：孔隙率一定时（含水率一定时），两种土体电阻率与含水率（孔隙率）之间均呈幂函数关系。两种土体电阻率均随含水率的增加先剧烈减小，而后逐渐变缓；均随孔隙率的增加而增加。两种土体电阻率均随体积含水率的增大而减小，红黏土电阻率与体积含水率间呈幂函数关系，粉质黏土电阻率与体积含水率间呈线性关系，基于体积含水率得到的两种土体电阻率经验公式相关性较高，可应用于红黏土、粉质黏土地区的岩土工程实践。

Experimental study on influences of moisture content and porosity on electrical resistivity of cohesive soil--Taking Guilin red clay and silty clay as examples

In order to obtain a quantitative relationship between soil electrical resistivity and moisture content and porosity, red clay and silty clay in Guilin were regarded as the research object,through a more strict experiment of single factor control,which was under the case of the other factors unchanged to discuss the change of electrical resistivity of two kinds of soil with moisture content (the soil type,porosity unchanged),porosity(the soil type,the moisture content unchanged),volumetric moisture content of soil which can reflect moisture content and voidage variation comprehensively is introduced to discuss the chang of electrical resistivity with the volumetric moisture content and establish electrical resistivity empirical formula based on volumetric moisture content.The test results show that, when the porosity is constant,the electrical resistivity of the two kinds of soils changes in a similar trend with the moisture content and the relationship between electrical resistivity and moisture content is power function,which decreases sharply first with the increase of moisture content,and then gradually slows down.When moisture content is constant,the electrical resistivity of the two kinds of soil presents an upward trend with the increase of porosity,and the relationship between electrical resistivity and porosity is a power function.Electrical resistivity of both kinds of soil decreases with increasing of volumetric moisture content.There is a power function relationship between the electrical resistivity and the volumetric moisture content of red clay.There is linear relationship between electrical resistivity and the volumetric moisture content of silty clay.The empirical formula of electrical resistivityof two kinds of soil based on the volumetric moisture content has high correlation,which can be applied to the geotechnical engineering practice in red clay and silty caly areas.