土的微结构特征对其电阻率的影响试验研究

Effect of Microstructure on Soil Electrical Resistivity

土的电阻率是土的固有物性参数之一,可反映土的基本物理力学性质指标及结构特征等,具有重要的理论意义和应用价值。利用课题组研制的ESEU-1型土电阻率测试仪对膨胀土与黄土的电阻率进行测试,主要研究了孔隙率、孔隙结构等土的微结构特征对电阻率的影响规律。研究结果表明:孔隙率与孔隙结构等土的微结构特征对土的电阻率存在显著的影响,微结构不同、其他条件相同的土样的电阻率存在较大差别,且在水与导电性良好的NaCl溶液中饱和后的大小与变化规律也不一致。

Soil electrical resistivity is one of the fundamental physical property parameters of the soil, and is closely related to the properties of physical, mechanical parameters and microstructure characteristics of the soil. This paper studies the effect of microstructure characterization on soil electrical resistivity. To meet these objectives, a comprehensive laboratory testing program was carried out on an expansive soil sampled from Hefei city and a loess soil sampled from Xi＇an city. The results show that microstructure （including porosity, pore structure, pore connectivity etc.） has a notable effect on soil electrical resistivity. As other conditions being equal, the samples vary in microstructure exist of different electrical resistivity before permeation, and different variation in electrical resistivity after permeated in water or NaC1 solution.