水利学报2017，Vol.48Issue(9)：1107-1117,1125,12.DOI:10.13243/j.cnki.slxb.20160639
基于离散元的颗粒材料三维临界状态与剪胀特性研究
Three-dimensional critical state and dilatancy of granular materials based on DEM
摘要
Abstract
As an important part of classical soil mechanics,the critical state is always regarded as a referent state in the foundation of the constitutive model of the granular materials,such as sandy soil.According to the microscopic structure of sandy soils,the state parameter was proposed to describe the internal structure of sand,and series of state-dependent dilatancy theory were established.However,owing to the limitation of the experimental condition,researches of granular materials' critical state and dilatancy are usually investigated by the conventional triaxial tests,without the consideration of the intermediate principle stress.Researches have shown that the loading path have some effects on the mechanical response of granular materials.In this paper,true triaxial tests are conducted using Discrete Element Method (DEM),the stress-strain behaviors are analyzed during the loading process,and the influence of the intermediate principle stress ratio on the critical state is shown.The critical state line is unique in the e-log p plane,irrelevant with the intermediate principal stress ratio.A three-dimensional state-dependent dilatancy equation is suggested by introducing the shape function.The relationship of the critical stress ratio and the Lode angle can be approximately described by a shape function.The numerical simulations show that the proposed three-dimensional equation can reflect the dilatancy behaviors of granular materials under complex loading paths,however it needs more verification of laboratory tests and theories.关键词
颗粒材料/真三轴试验/离散元/临界状态/剪胀性/状态参量Key words
granular materials/true triaxial test/DEM/critical state/dilatancy/state parameter分类
建筑与水利引用本文复制引用
刘嘉英,马刚,周伟,常晓林..基于离散元的颗粒材料三维临界状态与剪胀特性研究[J].水利学报,2017,48(9):1107-1117,1125,12.基金项目
国家自然科学基金面上项目(51579193)、国家自然科学基金青年基金项目(51509190)、中国博士后科学基金面上项目(2016T907272) （51579193）
