中文摘要：

渗透性影响土体工程地质特性与力学行为,要对渗透系数进行理论估算相当困难。为应用泊肃叶定律建立土体渗透系数的估算模型,引入等效渗透管径概念并推导其关系式,利用针对性渗透试验对模型合理性与适用性进行校验。结果表明：土体内部渗透通道可借助等效性原理给予等效细管化;等效渗透管径的关系式,能够考虑土体密实度、结合水含量和颗粒级配、排布方式、几何形状等;模型的计算结果与试验数据较为一致,在误差控制方面表现良好。基于泊肃叶定律的土体渗透系数估算模型,各关键参量具有相对严格的物理背景,物理含义较为明确;可能适用的土体粒径范围为0.002~0.500 mm,大致覆盖上至中砂粒、下至粗粘粒包含的区间。

英文摘要：

Calculating the permeability of soil theoretically is very difficult due to complexity of soil properties. A concept of equivalent pipe-diameter was introduced and a mathematical expression was derived in the paper for the estimation of soil permeability based on Poiseuille′s law. The rationality and applicability of the model were carefully checked against the special laboratory data of permeability tests. Results showed that the percolation path of soil could be converted into a series of thin pipes by means of the equivalence principle. The mathematical expression of equivalent pipe-diameter considered the influencing factors to soil permeability,such as the compactness,bound water content,particle grading,pattern distribution and geometric shape of soil particles. The model produced results in agreement with the laboratory data. The estimation model was found to be applicable to the soils with the particle sizes between 0.002 mm（lower bound of coarse clay,0.002 mm） and 0.500 mm（upper bound of medium sand,0.500 mm）.