Constitutive Model for Clays Under the ISA Framework
The Intergranular Strain Anisotropy ISA framework is a novel approach to develop elastoplastic models wherein a yield surface is defined in terms of strain increments. For this purpose, the loading-unloading conditions are satisfied within the space of the intergranular strain, this latter being a state variable “following” the strain rate. With this, the model aims to improve the simulations under cyclic loading while keeping their good capabilities at monotonic loading. Within this article, a constitutive model for clays is developed under the ISA plasticity framework. The model adopts some parameters from the modified Cam-Clay model and others to describe the evolution of the integranular strain and its effect on the model response. Some illustrative simulations are provided to analyze the model performance under cyclic loading. The simulations show a qualitative behavior in agreement with some experiments. Possible improvements are discussed at the end of the article.
KeywordsClay model ISA plasticity Intergranular strain
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