岩土工程学报2017，Vol.39Issue(5)：822-831,10.DOI:10.11779/CJGE201705006
考虑宽度与厚度的颗粒胶结模型理论分析
Analytical solutions to micro-bond model for particles considering width and thickness of bond
摘要
Abstract
In the DEM simulation of mechanical response of methane hydrate or weathered rock, the real shape and size of inter-particle bond significantly affect the macro-mechanical properties of the materials, therefore it is necessary to build a micro-bond model considering the width and thickness of the bond. The modified high-accuracy analytical solution is proposed according to the Dvorkin theory to determine the stiffness and strength of inter-granular bond in DEM. By introducing the symmetric displacement function, the symmetry and accuracy of the stress field are improved compared with the solution by the Dvorkin theory. The provided solutions are consistent with the FEM analysis results on a qualitative and quantitative level. For an application, the parametric investigation is carried out according to the analytical solutions. The influences of width and thickness on the stiffness of the bond are discussed firstly, and then the fitting formulas for three bond stiffnesses for the common materials are provided. Subsequently, the twin shear unified strength theory is applied to give the initial failure domain for the contact model for brittle and plastic bond materials, respectively, and the tensile/compressive-shear strength envelope is also put forward. The proposed solutions can provide a large number of data for mechanical response of the bond, and assist to set up the failure criterion under complex loading, which can validate and supply the experimental data in establishing the micro-bond model in DEM.关键词
离散元/胶结模型/Dvorkin理论/双剪统一强度理论Key words
DEM/micro-bond model/Dvorkin theory/twin shear unified theory分类
建筑与水利引用本文复制引用
王华宁,龚浩,李富根,蒋明镜..考虑宽度与厚度的颗粒胶结模型理论分析[J].岩土工程学报,2017,39(5):822-831,10.基金项目
国家自然科学基金项目(11572228,51639008) （11572228,51639008）
中央高校基本科研业务费专项资金—学科交叉类 （）
国家重点基础研究发展计划("973"计划)项目(2014CB046901) （"973"计划）
同济大学土木工程防灾国家重点实验室自主课题(SLDRCE14-B-11) （SLDRCE14-B-11）
