Capability of discrete element method to investigate the macro-micro mechanical behaviours of granular soils considering different stress conditions and morphological gene mutation  

作　　者：Wei Xiong Jianfeng Wang Zhuang Cheng 

机构地区：[1]Department of Architecture and Civil Engineering,City University of Hong Kong,Hong Kong,China [2]Shenzhen Research Institute of City University of Hong Kong,Shenzhen,China [3]School of Civil Engineering and Architecture,Wuhan University of Technology,Wuhan,China [4]Sanya Science and Education Innovation Park,Wuhan University of Technology,Sanya,China

出　　处：《Journal of Rock Mechanics and Geotechnical Engineering》2023年第10期2731-2745,共15页岩石力学与岩土工程学报（英文版）

基　　金：supported by the General Research Fund from the Research Grant Council of the Hong Kong SAR,China(Grant Nos.CityU 11201020 and CityU 11207321);the National Science Foundation of China(Grant No.42207185);the Contract Research Project from the Geotechnical Engineering Office of the Civil Engineering Development Department of Hong Kong SAR,China(Project Ref.No.CEDD STD-30-2030-1-12R);the BL13W beamline of Shanghai Synchrotron Radiation Facility(SSRF)。

摘　　要：Discrete element method(DEM)has been widely utilised to model the mechanical behaviours of granular materials.However,with simplified particle morphology or rheology-based rolling resistance models,DEM failed to describe some responses,such as the particle kinematics at the grain-scale and the principal stress ratio against axial strain at the macro-scale.This paper adopts a computed tomography(CT)-based DEM technique,including particle morphology data acquisition from micro-CT(mCT),spherical harmonic-based principal component analysis(SH-PCA)-based particle morphology reconstruction and DEM simulations,to investigate the capability of DEM with realistic particle morphology for modelling granular soils’micro-macro mechanical responses with a consideration of the initial packing state,the morphological gene mutation degree,and the confining stress condition.It is found that DEM with realistic particle morphology can reasonably reproduce granular materials’micro-macro mechanical behaviours,including the deviatoric stressevolumetric straineaxial strain response,critical state behaviour,particle kinematics,and shear band evolution.Meanwhile,the role of multiscale particle morphology in granular soils depends on the initial packing state and the confining stress condition.For the same granular soils,rougher particle surfaces with a denser initial packing state and a higher confining stress condition result in a higher degree of shear strain localisation.

关 键 词：Discrete element method(DEM) Spherical harmonic-based principal component analysis(SH-PCA) Particle morphology Granular so 

分 类 号：TG1[金属学及工艺—金属学]