Review of Elastic Visco-Plastic Modeling of the Time-Dependent Stress-Strain Behavior of Soils and Its Extensions and Applications

Abstract

This paper presents a brief review of the works of elastic visco-plastic (EVP) modelling of the time-dependent stress-strain behaviour of soils in one-dimensional straining (1D) and in 3D stress state. A few important concepts and their physical meanings are explained. The 1D EVP model is briefly reviewed with a comparison with the classic Maxwell’s rheological model. It is found that Yin and Graham’s 1D EVP model is an extension of Maxwell’s rheological model for considering the nonlinear behaviour of soils. A nonlinear creep function proposed by the author is presented. This function has been used in refined 1D and 3D EVP models. The recent extension of the EVP modelling framework to consider the swelling of a saturated soil is introduced. New developments and applications done by other researchers are also briefly summarized. It is found that, in general speaking, the EVP modelling framework is suitable as a theoretical basis for modelling the time-dependent stress-strain behaviour of many clayey soils. However, this framework shall be modified or extended to consider special characteristics of the viscous behaviour of soils such as swelling of saturated and unsaturated soils and other geomaterials.Keywordscreeptime effectsstrain-rate effectsvisco-plasticviscous