Abstract
Permeability tests have been widely used to estimate infiltration capacity of field soils. This study aims to discussthe applicability of borehole falling head tests (FHT) to the evaluation of saturated hydraulic conductivity (k0) of the soils under dry conditions. Parameters relating to soil properties are determined by preliminary analyses with the test data obtained in Tsurumi River Basin. Also, the validity of Glover's equation is examined, based on the formula proposed by ARSIT. In addition, an empirical formula specifying the initial condition of the surface soil layer is introduced on the basis of the field data observed by tensiometers, and its parameters are classified according to the season and soil depth. As a result, k0 values evaluated from FHT carried out for the dry Kanto loam soils are in good agreement with the values obtained by constant head tests and FHT under wet conditions.
