Simulation of Triaxial Tests for Unsaturated Soils under a Tension–Shear State by the Discrete Element Method

In this paper, the discrete element method is used to simulate triaxial tests of unsaturated soil under a tension–shear state. A relationship between water content and uniaxial tensile strength with different void ratios is obtained, which is applied to uniaxial tensile discrete element simulations to establish a relationship between grain-scale parameters and water content from back analysis. A group of triaxial simulations for unsaturated soil under a tension–shear state is then conducted. The discrete element method is used to obtain the relationship between deviatoric stress and axial displacement with different water contents, and also to reveal the effects of water content on peak strength and dilatancy phenomena with different confining pressures. The displacement fields of numerical specimen are analyzed qualitatively, and the mechanism and process of failure are discussed from the prospective of energy and dissipation.

[1]  Jipeng Xu,et al.  Numerical Simulation of Impact Rockburst of Elliptical Caverns with Different Axial Ratios , 2021, Sustainability.

[2]  B. Indraratna,et al.  Advancements in Geo-Inclusions for Ballasted Track: Constitutive Modelling and Numerical Analysis , 2021, Sustainability.

[3]  Jianzhuang Xiao,et al.  Discrete Element Simulation Analysis of Biaxial Mechanical Properties of Concrete with Large-Size Recycled Aggregate , 2021, Sustainability.

[4]  Bin Shi,et al.  Tensile strength of clayey soil and the strain analysis based on image processing techniques , 2019, Engineering Geology.

[5]  Liu Jun,et al.  Analysis of the thresholds of granular mixtures using the discrete element method , 2017 .

[6]  Wen-jie Xu,et al.  DEM analyses of the mechanical behavior of soil and soil-rock mixture via the 3D direct shear test , 2015 .

[7]  Chuangbing Zhou,et al.  Modelling desiccation cracking in thin clay layer using three-dimensional discrete element method , 2013 .

[8]  Peter Eberhard,et al.  A bonded-particle model for cemented sand , 2013 .

[9]  Sebastià Olivella,et al.  Crack patterns in clayey soils: Experiments and modeling , 2012 .

[10]  Ying Chen,et al.  Simulating shear behavior of a sandy soil under different soil conditions , 2011 .

[11]  Peter Eberhard,et al.  A discrete element model to describe failure of strong rock in uniaxial compression , 2011 .

[12]  T. Sitharam,et al.  Post-liquefaction undrained monotonic behaviour of sands: experiments and DEM simulations , 2009 .

[13]  Yi‐Feng Chen,et al.  Modeling coupled THM processes of geological porous media with multiphase flow: Theory and validation against laboratory and field scale experiments , 2009 .

[14]  Lyesse Laloui,et al.  Discrete element modelling of drying shrinkage and cracking of soils , 2009 .

[15]  Scott W. Sloan,et al.  Elastoplastic prediction of hydro-mechanical behaviour of unsaturated soils under undrained conditions , 2008 .

[16]  John A. Hudson,et al.  Numerical modelling of uniaxial compressive failure of granite with and without saline porewater , 2008 .

[17]  Yo-Ming Hsieh,et al.  Interpretations on how the macroscopic mechanical behavior of sandstone affected by microscopic properties—Revealed by bonded-particle model , 2008 .

[18]  X. Li,et al.  Thermodynamics-based constitutive framework for unsaturated soils. 2: A basic triaxial model , 2007 .

[19]  R. Broughton,et al.  Measurement of tensile strength of unsaturated sandy loam soil , 2005 .

[20]  P. Cundall,et al.  A bonded-particle model for rock , 2004 .

[21]  Serge Leroueil,et al.  Insight into shear strength functions of unsaturated granulates by DEM analyses , 2004 .

[22]  Simon J. Wheeler,et al.  Coupling of hydraulic hysteresis and stress–strain behaviour in unsaturated soils , 2003 .

[23]  A. Gens,et al.  An elasto-plastic model for unsaturated soil incorporating the effects of suction and degree of saturation on mechanical behaviour , 2003 .

[24]  Changfu Wei.  Static and dynamic behavior of multiphase porous media: Governing equations and finite element implementation. , 2001 .

[25]  J. Konrad,et al.  A idealized framework for the analysis of cohesive soils undergoing desiccation , 1997 .

[26]  Antonio Gens,et al.  A constitutive model for partially saturated soils , 1990 .

[27]  P. Cundall,et al.  A discrete numerical model for granular assemblies , 1979 .

[28]  R. H. G. Parry,et al.  Triaxial Compression and Extension Tests on Remoulded Saturated Clay , 1960 .

[29]  R. Haefeli,et al.  Investigation and Measurements of the Shear Strengths of Saturated Cohesive Soils , 1951 .