A new hardening function for bounding surface plasticity to predict soil behavior in overall strain ranges

Abstract

An elasto-plastic constitutive model based on an anisotropic hardening rule was proposed to model the stress-strain behavior from small to large strains. The anisotropic hardening rule was based on the generalization of isotropic hardening rule and included a simple hardening function with respect to a unique internal variable. However plasticity in reverse loading condition could be modeled by discrete formation of homology center. On weathered soils, two series of tests were performed: one is the undisturbed specimens at natural water content using resonant column, torsional shear and triaxial tests and the other is the reconstituted saturated specimens tested using triaxial tests under drained and undrained conditions. In addition undrained triaxial tests were performed for clays with various overconsodilation conditions. The proposed model calculated the stress-strain relationship and the secant modulus and they match reasonably with the measured ones in overall strain ranges.