ABSTRACT
In situ measurements of field-saturated hydraulic conductivity, Kfs , are essential for accurate prediction of water movement in soil. The practical applicability of the pressure infiltrometer (PI) method to measure Kfs of soil is examined using field and laboratory tests and numerical calculations. Sand and loam soils were selected for the study. Theoretical features of the PI method are explained by the field permeability tests and the numerical calculations. It is shown that the PI method can be an excellent practical in situ permeability test. It is suggested that about 0.06 cm−1 or some smaller value of α* may be more appropriate for sand and loam in calculating Kfs of soil, and that the measurement depth of the PI method can be controlled by combining the radius and insertion depth of the ring, and the constant head imposed on the soil surface within the ring.
