Application of a Stress-Fractional Model for Capturing the Stress-Strain Behavior of Granular Soils

Wei Lu,Jinan Wang,Jiangong Yang,Hadi Hasanzadehshooiili

doi:10.1155/2021/2617315

Wei Lu, Jinan Wang + Show 2 more

Open Access

https://doi.org/10.1155/2021/2617315

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Abstract

Granular soils usually serve as the filler material in geotechnical engineering. This study presents the development and application of a stress-fractional model for granular soils with different initial material states. To capture the plastic loading and flow behaviors, a subloading surface with the fractional stress gradient is used. The developed model contains twelve parameters which can be determined through triaxial tests. To validate the developed model, the well-documented test results of Firoozkuh No. 161 sand and crushed basalt are simulated and discussed. It is found that the stress-fractional model can reasonably simulate the undrained and drained behaviors of granular soils consolidated with different densities and mean effective pressures.

Highlights

Granular soils, e.g., ballast and sand, are often encountered or used in engineering practice
During the whole operation period, a rail track usually experiences a large number of repeated train loads
A series of elegant constitutive models have been developed for predicting the instability and flow liquefaction behavior of Firoozkuh sand [2] as well as other sands

Summary

Introduction

E.g., ballast and sand, are often encountered or used in engineering practice. Ballast usually serves as an essential track construction layer to bear the repeated moving load transmitted by the train. Accurate prediction of the corresponding maintenance periods necessitates the development of an advanced constitutive model that captures ballast or sand deformation [1]. Traditional elastoplastic constitutive models have been investigated widely and successfully applied in many fields, more effort is required to realistically describe the stress-strain relationship of granular soil, which was observed to be state-dependent and nonassociated. Is study attempts to develop a statedependent constitutive model for granular soil by using the fractional plasticity and subloading surface concepts [8]. This study is limited to homogenous materials under isotropic or anisotropic consolidation

Constitutive Model

Numerical Implementation