MEASUREMENT OF HYDRAULIC CONDUCTIVITY OF UNSATURATED SANDY SOILS USING APPROXIMATED PROFILE METHOD

Abstract

The instantaneous profile method is favorable for measuring hydraulic conductivity of unsaturated soils. However, it requires the use many expensive measuring sensors and a large amount of soils, and in the case of fine grain soils, it is difficult to set up the specimen. Therefore, an experiment method has been development in Chubu University. It is an improved type of the original instantaneous profile method, and characterized by linear approximation of soil moisture distribution. Application of this experiment method is discussed in comparison with other steady state methods. From the experimental results, it is clarified that hydraulic conductivity of unsaturated sandy soil with large grain size and with narrow grain size distribution is decreased by orders of magnitude in higher degree of saturation.