The conventional oedmeter test based on Terzaghi's one dimensional consolidation theory is not applicable to very soft clays with high water content. As an alternative method, the constant rate of strain consolidation test (CRS-test) is proposed to determine the consolidation constants for them. By measuring the axial load, the axial displacement and pore pressure at the base of the specimen during CRS- consolidation process the f-logp' relationship and the coefficient of consolidation, Cv are determined on the basis of consolidation theory in which the thickness of clay specimens is variable.
　The self-weight consolidation was performed in the model clay layer with depth of 90 cm, in which settlements and pore pressures were measured in every layer of 10 cm. These consolidation phenomena were analysed by using the consolidation constants obtained from the above-mensioned procedure.
　it is found that CRS-test may be applicable to very soft clays as an alternative method of the conventional oedmeter test.