Quantitative shear strength–consolidation stress–void ratio interrelations for reconstituted clays

Abstract

Isotropically and anisotropically consolidated undrained triaxial compression shear tests are conducted on 87 specimens of eight kinds of clays reconstituted over a wide spectrum of initial water contents. These data in conjunction with those of 55 specimens previously published by the authors and their research team are used to investigate the shear strength–compressibility interrelation for reconstituted clays. The effects of the initial void ratio and the consolidation stress path on both the consolidated undrained shear strength–consolidation effective stress relationship and the compression curves in terms of the void ratio against the consolidation effective stress are investigated. It is found that the consolidated undrained shear strength–void ratio relationship is independent of the initial void ratio and the consolidation stress path, and a quantitative expression is proposed for determining the relationship as a function of the void ratio at the liquid limit. Meanwhile, the compression curves of reconstituted clays at different values of the initial void ratio and the void ratio at the liquid limit from different consolidation stress path tests can be normalised into a unique line with the application of the intrinsic compression framework. Accordingly, a quantitative expression can be established to determine the relationship between the consolidated undrained shear strength and the effective consolidation stress. The validity and accuracy of the proposed equations are discussed based on data from independent researchers and from the research team.