不规则颗粒及其集合体三维离散元建模方法的改进

金磊; 曾亚武; 叶阳; 李晶晶

doi:10.11779/CJGE201707014

不规则颗粒及其集合体三维离散元建模方法的改进 English Version

金磊^{1, 2},
曾亚武^1, ,,
叶阳¹,
李晶晶³

1. 武汉大学土木建筑工程学院,湖北武汉 430072;
2. 武汉轻工大学土木工程与建筑学院,湖北武汉 430023;
3. 中国科学院武汉岩土力学研究所岩土力学与工程国家重点实验室,湖北武汉 430071

基金项目: 国家自然科学基金项目（41272342）

详细信息

作者简介:
金磊(1989- ),男,博士,讲师,主要从事复杂岩土体三维颗粒离散元建模及其变形破坏机理等方面的研究。E-mail: whujinlei@whu.edu.cn。

通讯作者:
曾亚武，E-mail：zengyw@whu.edu.cn

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- 文章访问数: 477
- HTML全文浏览量: 5
- PDF下载量: 496
出版历程
- 收稿日期: 2016-03-30
- 发布日期: 2017-07-24

Improving three-dimensional DEM modeling methods for irregularly shaped particles and their assembly

JIN Lei^{1, 2},
ZENG Ya-wu^1, ,,
YE Yang¹,
LI Jing-jing³

1. School of Civil Engineering, Wuhan University, Wuhan 430072, China;
2. School of Civil Engineering and Architecture, Wuhan Polytechnic University, Wuhan 430023, China;
3. State Key Laboratory of Geomechanics and Geotechnical Engineering, Institute of Rock and Soil Mechanics, Chinese Academy of Sciences, Wuhan 430071, China

摘要

摘要: 以土石混合体中的不规则块石和含石量为40%的土石混合体室内大三轴试样为例,研究了如何针对当前岩土材料建模方法的不足进行改进以建立尽可能真实的不规则颗粒及其集合体的三维离散元模型。为了模拟块石的真实形态特征,明确了块石几何模型建模方法的控制参数及其确定方法,建立了与真实块石球度相同、棱角度相似的三维半真实离散元模型。为了计算模型的体积以用于模型密度优化及颗粒集合体孔隙率的计算,提出了一种三维离散元模型虚拟切片技术,结合数字图像处理技术可快速准确计算块石三维半真实离散元模型的体积。为了使得土石混合体大三轴试样三维离散元模型的密实度与室内试样保持一致并兼顾建模效率,提出了基于拟振动压实法和分层复制法的土石混合体大三轴试样三维离散元建模方法。研究结果表明：所提出的不规则块石几何模型建模方法控制参数较少且可分别对球度和棱角度进行单独控制;当块石离散元模型填充球体数较少时,其体积与对应几何模型体积相差较大,不能直接采用对应几何模型的体积;所建立的土石混合体数值试样与室内试样的细观结构特征基本相同,即块石随机散布于土体基质中。
- 不规则颗粒 /
- 颗粒集合体 /
- 三维离散元建模 /
- 土石混合体 /
- 半真实离散元模型 /
- 虚拟切片技术
Abstract: Based on the irregularly shaped rock blocks in soil-rock mixture (SRM) and the large-scale triaxial specimens of SRM with rock block proportion of 40% prepared indoor, this study aims at constructing three-dimensional DEM models for the irregularly shaped particles and their assembly as realistic as possible by improving the current modeling methods. To simulate the morphological characteristics of rock blocks, the controlling parameters of the proposed modeling methods for the geometric model for rock blocks and their evaluation methods are identified, and then the three-dimensional semi-real-shaped DEM models of rock blocks with identical sphericity and similar angularity are constructed. To obtain the volume of the rock block model for subsequent density optimization of rock block model and porosity calculation of particle assembly, a virtual slicing technique for three-dimensional DEM model is developed and adopted to evaluate the volume of the semi-real-shaped DEM models for rock blocks in combination with the digital image processing (DIP) technique. To efficiently build a SRM model whose relative density is consistent with the corresponding experimental specimens, a three-dimensional DEM modeling method for the large-scale triaxial specimens of SRM based on the quasi vibration and the compaction method and layered duplication method is proposed. The results show that the required sphericity and angularity can be simulated readily with fewer controlling parameters of the proposed modeling method for geometric model of rock blocks. When a rock block DEM model composed of a small number of packing spheres, a great deviation in the volume from the corresponding geometric model occurs. The numerical and experimental SRM specimens
- irregularly shaped particle /
- particle assembly /
- three-dimensional DEM modeling method /
- soil-rock mixture /
- semi-real-shaped DEM model /
- virtual slicing technique

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参考文献(19)

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文章访问数: 477
HTML全文浏览量: 5
PDF下载量: 496
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不规则颗粒及其集合体三维离散元建模方法的改进 English Version

作者简介: 金 磊(1989- ),男,博士,讲师,主要从事复杂岩土体三维颗粒离散元建模及其变形破坏机理等方面的研究。E-mail: whujinlei@whu.edu.cn。

通讯作者: 曾亚武，E-mail：zengyw@whu.edu.cn

计量

出版历程

Improving three-dimensional DEM modeling methods for irregularly shaped particles and their assembly

计量

出版历程

目录

作者简介:
金磊(1989- ),男,博士,讲师,主要从事复杂岩土体三维颗粒离散元建模及其变形破坏机理等方面的研究。E-mail: whujinlei@whu.edu.cn。

通讯作者:
曾亚武，E-mail：zengyw@whu.edu.cn