Energy Consumption Analysis of Frozen Sandy Soil and an Improved Double Yield Surface Elastoplastic Model considering the Particle Breakage

Junlin He,Zuyin Zou,Yuanze Zhang,Fei Luo,Zhanyuan Zhu

doi:10.1155/2019/9716748

Junlin He, Zuyin Zou + Show 3 more

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https://doi.org/10.1155/2019/9716748

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Abstract

The stress-strain relationship of frozen soil is a hot research topic in the field of frozen soil mechanics. In order to study the effect of particle crushing on the stress-strain relationship, a series of triaxial compression tests for frozen sandy soil are performed under confining pressures from 1 to 8 MPa at the temperatures of −3 and −5°C, and the energy consumption caused by particle breakage is analyzed during the triaxial shear process based on the energy principle. It is found that the energy consumption caused by the particle breakage presents a hyperbolic trend with axial strain. In view of the obvious advantages of the double yield surface elastoplastic model in describing soil dilatancy, stress path effect, and stress history influence, a modified double yield surface elastoplastic model for frozen sandy soil is proposed based on the energy principle. The validity of the model is verified by comparing its modeling results with test results. As a result, it is found that the stress-strain curves predicted by this model agree well with the corresponding experimental results under different confining pressures and temperatures.

Highlights

Frozen soil, a kind of special geotechnical material, is defined as soil and rock constituents that contain ice with temperatures equal to or below zero [1]. ere are 35,760,000 km2 of permafrost in the world, which accounts for approximately 24% of the world’s land area [2]. e permafrost regions are mainly distributed in 48 countries, including Russia, the United States, Canada, and China [3]
During the loading process, some researchers use the dissipative energy to judge and evaluate the structural damage or the soil liquefaction [7,8,9]. e yield function can be established based on the energy principle of establishing the elastoplastic model, and in this respect, this mechanism is more often used, like the classic Cambridge model [10] where the work done by the external force equals the energy dissipated by the friction. en the energy balance equation is derived from the dilatancy equation under the axial condition, and this is the basis for establishing the yield function. erefore, a more complete energy dissipation analysis of the material can provide a basis for establishing a more complete and rational constitutive model
Particle crushing affects the mechanical properties of soil due to the gradation and structural change in soil, which is an important research topic in the field of soil mechanics [12], but there are few studies on the particle crushing of frozen sandy soil and only stay in the experimental stage

Summary

Introduction

A kind of special geotechnical material, is defined as soil and rock constituents that contain ice with temperatures equal to or below zero [1]. ere are 35,760,000 km2 of permafrost in the world, which accounts for approximately 24% of the world’s land area [2]. e permafrost regions are mainly distributed in 48 countries, including Russia, the United States, Canada, and China [3]. E above constitutive models based on the energy balance equation considering particle breakage are all singleyield surface constitutive models, which can obtain satisfactory results under general loading conditions, while double yield surface models have shown significant advantages in reflecting the soil dilatancy, the stress path influence, and the stress history effect.

Results

Conclusion