基于电阻率的砂土渗透系数测试方法

Measurement of sands permeability coefficient based on electrical resistivity

为了实现土体渗透系数的实时检测,利用电阻率测试无损和快速的优点,对砂土的电阻率及常水头渗透进行了检测试验,研究了砂土渗透系数和结构因子随孔隙率的变化规律,讨论了渗透系数与结构因子的关系.试验结果表明:渗透系数随着孔隙率的增加而增加,均值粒径越大,渗透系数增加越快;结构因子随孔隙率的增大而减小,结构因子越小,渗透系数越大;并给出了渗透系数与结构因子的关系式,由结构因子换算得到的渗透系数与常水头测试的结果一致.

In order to realize the real-time test of soil permeability coefficient,a new method for testing the permeability coefficient by using electrical resistivity measurement is introduced.The resistivity test is non-destructive and rapid,therefore the resistivity and permeability coefficient test of saturated clean sand is carried out.The experiments show that the permeability coefficient increases with the increase of the porosity and grows faster with the increase of the mean particle size.At the same time,the formation factor decreases with the increase of the porosity.It is found that the smaller the formation factor,the larger the permeability coefficient.A formula for permeability coefficient and formation factor is presented,the permeability coefficient obtained from the conversion of formation factors is in good agreement with that obtained from the constant head permeability test.This formula can be applied to the research the effects of permeability coefficient change in the engineering problems.