王智超,旷杜敏,赵涛.无胶结材料的离散元微观参数交互作用研究[J].计算力学学报,2017,34(6):755~762 |
| 码上扫一扫! |
无胶结材料的离散元微观参数交互作用研究 |
Investigation on interaction of microscopic parameters of cohesioness granular material via DEM |
投稿时间:2016-12-08 修订日期:2017-02-28 |
DOI:10.7511/jslx201706012 |
中文关键词: 离散单元法 抗转动 微观参数 交互作用 析因试验设计 |
英文关键词:discrete element method rolling resistance microscopic parameters interaction factorial experiment design |
基金项目:国家自然科学基金(51308485);湖南省自然科学基金(2016JJ2133);地质灾害防治与地质环境保护国家重点实验室开放基金(SKLGP2016K022)资助项目. |
|
摘要点击次数: 1812 |
全文下载次数: 1565 |
中文摘要: |
为研究无胶结材料离散元参数之间的交互影响,采用抗转动模型进行三轴排水试验模拟。首先,采用完全试验设计方法和析因试验设计方法,分别对宏微观参数相依规律以及参数之间的交互作用进行定性分析;然后,采用多元非线性回归分析方法对其进行定量分析,并提出了考虑交互作用的宏微观参数换算理论公式。着重探讨了无胶结材料微观参数中的刚度比α=ks/kn(0.3~0.9)、滚动刚度系数β(0.1~3)、颗粒内摩擦角θ(10~40)、法向接触刚度kn(1×107~7×107)以及塑性弯矩系数η(0.1~3)与材料宏观力学性质峰值应力σp、残余强度σr、弹性模量E、泊松比ν以及内摩擦角φ之间的相关关系。研究结果表明,(1)颗粒材料的宏观强度参数主要受颗粒内摩擦角以及抗转动参数影响,而其变形参数主要由颗粒接触刚度及接触刚度比控制;(2)各个微观参数之间就存在不同程度的交互作用,且交互作用对试样宏观性质将产生一定影响;(3)对峰值强度、残余强度和宏观内摩擦角而言,两抗转动参数之间以及抗转动参数与颗粒内摩擦角之间存在较强交互作用。对于宏观弹性模量和泊松比而言,颗粒接触刚度和颗粒接触刚度比与其他微观参数产生较强的交互作用。研究成果对合理科学地确定离散元模型的微观参数具有一定的指导意义。 |
英文摘要: |
In order to investigate the interaction of microscopic parameters of cohesioness granular materials,rolling resistance contact model was employed in triaxial compression test with different microscopic parameters via the Discrete Element Method.In this simulation,five microscopic parameters were adopted,namely,contact stiffness ratio α=ks/kn(0.3~0.9),coefficient of rolling stiffness β(0.1~3),normal stiffness kn(1×107~7×107),internal friction angle θ(10~40)and coefficient of plastic moment η (0.1~3),respectively.Meanwhile,parametric studies on five macroscopic parameters,namely,peak stress σp,residual strength σr,Young's modulus E,Poisson's ratio ν and friction angle φ were made.Firstly,comprehensive and factorial experiment design were carried out to conduct a qualitative analysis on the interaction between microscopic parameters and macroscopic parameters,and then multiple nonlinear regression was adopted to analyze the interaction quantitatively.A theoretical formula between macroscopic and microscopic parameters was proposed also,taking the interaction into consideration.The result shows that:(1) Particle internal friction angle and rolling resistance parameters have a significant influence on macroscopic strength parameters,and its deformation parameters are mainly determined by particle contact stiffness and contact stiffness ratio;(2) There are interactions between microscopic parameters and macroscopic parameters at different degrees,which have certain effects on the samples macroscopic properties;(3) As to peak stress,residual stress and internal friction angle,the interactions between two rolling resistance parameters,as well as rolling resistance parameters and particle friction angle are relatively strong.Furthermore,there is a significant interaction between normal contact stiffness and other parameters,which has an influence on Young's modulus and Poisson's ratio.The study contributes to quickly and reasonably determine the microscopic parameters of DEM model. |
查看全文 查看/发表评论 下载PDF阅读器 |
|
|
|
|