Permeability test of unsaturated soil approximating moisture distribution

摘要

An experiment method has been developed in Chubu University to estimate the permeability of unsaturated soils. It is an improved type of the original instantaneous profile method, and is able to measure the permeability of many kinds of soils. The new method is characterized by the unsteady condition of water profile and linear approximation of moisture distribution. This improved instantaneous profile is applicable to clayey soils or sand. There is a considerable volume change of soil draining in this test. Volume change of the specimen affects the measured permeability in this method, therefore, the authors correct the volume of the specimen by the water retention curves considering bulk density. In this paper, the proposed method is investigated using an indirect method with function models of the water retention curve and the inverse problem method.