The hydraulic conductivity is a key parameter in geotechnical engineering. It is closely associated to soil microstructure. In practice, consolidation stress, dry density, and natural structure of soil can affect pore diameter and distribution of soil. Thus, to investigate soil hydraulic conductivity, their effects on microstructure and the corresponding hydraulic conductivity were analyzed. The undisturbed soil and the remolded soil with different dry densities were studied by the oedometer tests, hydraulic conductivity tests, and field emission scanning electron microscope (FESEM) tests. The results indicate that the natural structure inside the undisturbed soil is the intrinsic reason that affects hydraulic conductivity. The increase of consolidation stress mainly reduces the number and size of interaggregate pores in terms of provoking aggregation of soil particles. The increase in dry density will fill the interaggregate pores and weaken their connectivity. The area percentage of macropores can be used to reflect the change of soil microstructure. The consolidation stress is the main factor dominating the area percentage of macropores under a high-stress level. A stable intrinsic structure will be developed to inhibit the soil deformation when dry density is 1.4 g/cm³ or above, which helps to restrain the reduction of area percentage and slow down the decrease of hydraulic conductivity. Finally, a brief statistical regression analysis indicates that the area percentage of pores whose diameter larger than 0.4 μm is significantly related to the hydraulic conductivity, which are responsible for seepage in soft clay.

导水率是岩土工程中的关键参数。它与土壤的微观结构密切相关。实际上，固结应力，干密度和土壤的自然结构会影响土壤的孔径和分布。因此，为了研究土壤的水力传导率，分析了它们对微观结构的影响以及相应的水力传导率。通过里程表测试，水力传导率测试和场发射扫描电子显微镜（FESEM）测试研究了干密度不同的原状土和重塑土。结果表明，原状土壤内部的自然结构是影响水力传导性的内在原因。固结应力的增加主要是在促使土壤颗粒凝结方面减少了凝结孔的数量和大小。干密度的增加将填充相互聚集的孔并削弱其连通性。大孔面积百分比可以用来反映土壤微观结构的变化。在高应力水平下，固结应力是决定大孔面积百分比的主要因素。当干密度为1.4 g / cm时，将开发出稳定的内在结构来抑制土壤变形 在高应力水平下，固结应力是决定大孔面积百分比的主要因素。当干密度为1.4 g / cm时，将开发出稳定的内在结构来抑制土壤变形 在高应力水平下，固结应力是决定大孔面积百分比的主要因素。当干密度为1.4 g / cm时，将开发出稳定的内在结构来抑制土壤变形³或更高，这有助于抑制面积百分比的降低并减缓水力传导率的降低。最后，简短的统计回归分析表明，直径大于0.4μm的孔的面积百分比与导水率显着相关，这是导致软粘土中渗流的原因。