Constitutive modeling of principal stress rotation associated with sand under simple shear loading

Abstract

An elasto‐plastic constitutive model is proposed to account for the effect of principal stress rotation that commonly occurs and significantly influences soil behavior. The model is based on a concept of adding plastic strain increments obtained from two mobilized planes: a plane of maximum shear stress which swings as the principal stress rotates, and a horizontal plane which is spatially fixed. Models based on the plane of maximum shear stress alone are particularly sensitive to horizontal effective stress ratio K0 (=σ′x/σ′y), whereas the proposed model gives a similar skeleton behavior for soils at the same density and mean effective stress, regardless of the value of K0, as observed in laboratory tests. The model is firstly calibrated by data from drained and undrained monotonic and cyclic Direct Simple Shear (DSS) tests on K0‐consolidated specimens of Nakdong River sand in loose and dense states. The capability of the proposed model in modeling of the conventional liquefaction effects: initial shear stress condition α (=τ′xy/σ′y) with Kα corrections, and initial confining stress condition σ´y with Kσ corrections, is also emphasized in this paper.

Effect of particle shape on cyclic liquefaction resistance of granular materials

“…Many factors, including soil type, consolidation state, and drainage condition, can influence soil cyclic behavior and accelerate or slow down the process of approaching liquefaction [e.g., 12,48,13,23,49,54]. Understanding the impact of these factors is valuable for assessing and potentially enhancing the effectiveness of current constitutive models when simulating the cyclic liquefaction of granular materials [e.g., 38,59,15,51,32]. Soil type encompasses particle or granular-level characteristics such as particle mineralogy, particle size distribution (PSD), and particle shape.…”

Modified SANISAND‐F model for simple shear path

“…In the past decades, different constitutive models had been proposed. Based on the typical shear characteristics of slip zone soil, a statistical damage model was proposed by Zou et al 12 Park et al 13 developed a non-coaxial model for soils particularly under simple shear loading, through adding plastic strain increments from a plane of maximum shear stress induced by PSR. Moscariello et al 14 proposed a generalized plasticity model based on an isotropic hardening rule and a density-dependent critical state line.…”

“…Based on the typical shear characteristics of slip zone soil, a statistical damage model was proposed by Zou et al 12 . Park et al 13 . developed a non‐coaxial model for soils particularly under simple shear loading, through adding plastic strain increments from a plane of maximum shear stress induced by PSR.…”