K₀, λ, κof Ariake Clay

Abstract

Ariake clay deposits are under the normally consolidated condition. In this paper, for undisturbed Ariake clay samples one-dimensional consolidation tests capable of measuring the lateral pressure and isotropic consolidation tests by the conventional triaxial apparatus were carried out to investigate on the coefficient of earth pressure at rest, K₀, compression index, λ, and swelling index, κ. As the result, it was cleared that the K₀-value of Ariake clay in the normal consolidation process indicated the minimum value (0.2-0.5) under the consolidation pressure equal to the consolidation yield stress (equal to the effective overburden pressure) and the constant value (0.45-0.65) under the consolidation pressure 4-6 times greater than the consolidation yield stress. Moreover, it was found that the K₀-value under the overconsolidated condition due to unloading increased in proportion to the m power of overconsolidation ratio, and the value of m was constant (0.46-0.53) to irrespective of plasticity index.