Abstract
This paper presents a new three-dimensional elastic viscoplastic (3D EVP) constitutive model for the time-dependent stress-strain behaviour of both normally consolidated and overconsolidated clays. There are two major new developments in the 3D EVP model: (i) incorporation of a nonlinear creep function with a limit for the creep volume strain under isotropic stressing conditions; (ii) adoption of a new loading surface function with a smooth shape on the π plane. Based on the "equivalent time" concept of Yin and Graham, the formulation of the new 3D EVP model is derived using the new nonlinear creep function and loading surface function. A new approach to determining all model parameters is presented. The 3D EVP model is calibrated using data from one conventional isotropic stress creep test and consolidated-undrained triaxial tests on soft Hong Kong marine deposits (HKMD). The model is verified by comparing model results with those from both normally and overconsolidated triaxial tests on HKMD and a mixture of kaolin and bentonite.
Original language | English |
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Pages (from-to) | 157-173 |
Number of pages | 17 |
Journal | Canadian Geotechnical Journal |
Volume | 39 |
Issue number | 1 |
DOIs | |
Publication status | Published - 13 Apr 2002 |
Keywords
- Clay
- Constitutive model
- Creep
- Equivalent time
- Stress-strain
- Time-dependent
- Verification
- Viscoplastic
ASJC Scopus subject areas
- Geotechnical Engineering and Engineering Geology