二维静态颗粒体系中拓扑结构与应力关系的研究

项目名称： 二维静态颗粒体系中拓扑结构与应力关系的研究

项目编号： No.11264006

项目类型： 地区科学基金项目

立项/批准年度： 2013

项目学科： 数理科学和化学

项目作者： 胡林

作者单位： 贵州大学

项目金额： 60万元

中文摘要： 静态颗粒物质的宏观物理性质与其微观结构、相互作用有密切的关系，可以从多个尺度对其物理行为进行研究。对于应力问题，已有的研究主要集中于宏观层面，通过实验测量颗粒堆边界上的应力分布、或者通过适当的假设引入本构方程解释实验结果，但至今仍未找到能解释各种实验结果的本构方程。最近的理论研究结果表明，微观拓扑结构能在一定程度上决定宏观应力的性质，然而这方面的研究还很不深入，也极少见到相关的实验研究。本项目拟通过实验构造不同拓扑结构的二维颗粒体，用自制的双轴测试仪测量边界处的正应力和切应力，用图像采集和分析系统获取颗粒体的拓扑结构，从而研究颗粒体的粗粒化应力张量与拓扑结构的关系；并且结合理论分析和计算机模拟研究这些关系随颗粒形状、摩擦系数、弹性模量、边界条件等因素变化的规律。研究结果对于理解颗粒堆的稳定性、崩塌、颗粒流等问题具有重要的科学价值，同时也对某些工程实践和灾害防治具有指导意义。

中文关键词： 颗粒物质；转向系数；应力张量；拓扑结构；离散元模拟

英文摘要： Static granular material widely found in industrial and agricultural production, daily life, nature, and its macroscopic physical properties are related to their microstructure and interactions, the relevant research on their behavior can be carried out from more than one scale. The existing research on stress research mainly focuses on the macro level by experimentally measuring the stress distribution on the boundary of particle heap, or the introducing some appropriate assumptions to the constitutive equation in order to explain the experimental results, but the constitutive equation that can be used to explain the experimental results has not yet been found. The results of recent studies show that the micro-topology to a certain extent determines the nature of the macroscopic stress, but the research in this area is not thorough.This project experimentally constitutes two-dimensional particle system with different topology, whose normal stress and shear stress on the boundary of the particle system will be measured by homemade biaxial tester, the topological structure of the particle system is also be obtained with an image acquisition and analysis system, based on the experiments, the relation between the coarse-grained stress tensor and the topological structure can be investigated further. And the combina

英文关键词： Granular matter；Janssen’s coefficient；Stress tensor；Topological structure；DEM simulation