不等向固结时混合土剪切行为的离散元分析

朱艳贵

doi:10.3724/j.gyjzG22062701

不等向固结时混合土剪切行为的离散元分析

doi: 10.3724/j.gyjzG22062701

朱艳贵

中铁第一勘察设计院集团有限公司, 西安 710043

基金项目:

国家自然科学基金项目（51809292）； 2022KY35YB-05PT陕西省高速铁路地质路基创新团队中国国家铁路集团有限公司科技研究开发计划项目（P2021G047）；中铁第一勘察设计院集团有限公司科研项目（2021KY85ZD(LSJT)-01）。

详细信息

作者简介:
朱艳贵，博士。电子信箱： zyg_csu@163.com

计量
- 文章访问数: 23
- HTML全文浏览量: 3
- PDF下载量: 0
- 被引次数: 0
出版历程
- 收稿日期: 2022-06-27
- 网络出版日期: 2024-05-29

Discrete Element Method Analysis on Shear Responses of Mixed Soil During Anisotropic Consolidation

ZHU Yangui

China Railway First Survey and Design Institute Group Co., Ltd., Xi'an 710043, China

摘要

摘要: 为探明初始应力比影响不同细颗粒含量密实混合土的宏观剪切行为的细观机制，采用离散元法研究混合土的宏细观剪切行为。混合土由球形细颗粒和真实角砾形状粗颗粒组成。结果表明：初始应力比增大可以使混合土的初始加载阶段内摩擦角和剪胀角增大。通过分析粗颗粒–粗颗粒、粗颗粒–细颗粒、细颗粒–细颗粒接触的贡献大小，发现初始应力比对混合土的工程分类基本无影响。混合土的初始加载阶段，剪切强度随着初始应力比的增大而增大，与颗粒间接触力增大密切相关。在混合土的初始加载阶段，随着初始应力比的增大，内摩擦角的增大可归因于接触、法向接触力、法向和切向枝向量的各向异性增大程度之和超过了切向接触力的各向异性的减小程度。
- 混合土 /
- 宏细观特性 /
- 数值计算 /
- 初始应力比 /
- 接触类别
Abstract: To explore the microscopic mechanisms of the macroscopic shear responses of dense-mixed soil with different contents of fine particles affected by initial stress ratios, the discrete element method was used to study the macroscopic and microscopic shear responses of mixed soil. Mixed soil consisted of spherical fine particles and coarse particles with real gravel shapes. Research indicated that an increase in initial stress ratios could increase both friction and dilatancy angles at initial loading stages. It was found that initial stress ratios had little influence on engineering classifications of mixed soil by analyzing the contact contributions of coarse-coarse, coarse-fine, and fine-fine particles. With increase in initial stress ratios, the shear strength of mixed soil increased at initial loading stages, which was closely related to an increase in contact forces particles. With increase in initial stress ratios, the increase in internal fiction angles at initial loading stages could be attributed to the anisotropic increase degree of contact, normal contact force, normal and tangential branch vectors beyond the anisotropic decrease degree of tangential contact force.
- mixed soil /
- macroscopic and microscopic characteristics /
- numerical calculation /
- initial stress ratio /
- contact type

HTML全文

参考文献(27)

[1]	汪清净.不等向固结条件下砂土动力特性及强度归一化表征[D].杭州:浙江大学, 2012.
[2]	吴越,杨仲轩,徐长节.初始组构各向异性对砂土力学特性及临界状态的影响[J].岩土力学, 2016, 37(9):2569-2576.
[3]	姜景山,左永振,程展林,等.围压和密度对粗粒料临界状态力学特性的影响[J].长江科学院院报, 2021, 38(5):94-102.
[4]	SHI J, QIAN S, ZENG L L, et al. Influence of anisotropic consolidation stress paths on compression behaviour of reconstituted Wenzhou clay[J]. Geotechnique Letters, 2015, 5(4):275-280.
[5]	CAI Y Q, HAO B B, GU C, et al. Effect of anisotropic consolidation stress paths on the undrained shear behavior of reconstituted Wenzhou clay[J]. Engineering Geology, 2018, 242:23-33.
[6]	BERGADO D T, TAECHAKUMTHORN C, LORENZO G A, et al. Stress-deformation behavior under anisotropic drained triaxial consolidation of cement-treated soft Bangkok clay[J]. Soils and Foundations, 2006, 46(5):629-637.
[7]	DOROSTKAR O, MIRGHASEMI A A. Micro-mechanical study of stress path and initial conditions in granular materials using DEM[J]. Computational Particle Mechanics, 2016, 3(1):15-27.
[8]	ZHOU W, WU W, MA G, et al. Study of the effects of anisotropic consolidation on granular materials under complex stress paths using the DEM[J/OL]. Granular Matter, 2017, 76(19)[2022-06-27]. https://doi.org/10.1007/s10035-017-0763-0.
[9]	张波,陶连金,黄俊,等.基于微观图像处理技术的土体三轴试验颗粒流模型[J].工业建筑, 2013, 43(4):86-91.
[10]	吴东旭,姚勇,梅军,等.砂卵石土直剪试验颗粒离散元细观力学模拟[J].工业建筑, 2014, 44(5):79-84.
[11]	高文伟,高玮,胡瑞林,等.块石空间定向性对土石混合体力学性质的影响[J].防灾减灾工程学报, 2019, 39(1):89-97.
[12]	张敏超,刘新荣,王鹏,等.不同含石量下泥岩土石混合体剪切特性及细观破坏机制[J].土木与环境工程学报(中英文), 2019, 41(6):17-41.
[13]	张强,汪小刚,赵宇飞,等.土石混合体三维细观结构随机重构及其力学特性颗粒流数值模拟研究[J].岩土工程学报, 2019, 41(1):60-69.
[14]	GONG J, LIU J, CUI L. Shear behaviors of granular mixtures of gravel-shaped coarse and spherical fine particles investigated via discrete element method[J]. Powder Technology, 2019, 353:178-194.
[15]	杨升,李晓庆.基于3维离散元颗粒流的土石混合体大型直剪试验模拟分析[J].工程科学与技术, 2020, 52(3):78-85.
[16]	胡军霞,马一跃,张仕贤,等.不排水条件下土石混合料双轴压缩离散元模拟[J].计算力学学报, 2021, 39(5):661-669.
[17]	ROWE P W. Stress-dilatancy relation for static equilibrium of an assembly of particles in contact[C]//Proceedings of the Royal Society A:Mathematical, Physical and Engineering Sciences. 1962.
[18]	GUO N, ZHAO J D. The signature of shear-induced anisotropy in granular media[J]. Computers and Geotechnics, 2013, 47:1-15.
[19]	GOLDENBERG C, GOLDHIRSCH I. Friction enhances elasticity in granular solids[J]. Nature, 2005, 435(7039):188-191.
[20]	JIANG M J, SHEN Z, WANG J F. A novel three-dimensional contact model for granulates incorporating rolling and twisting resistances[J]. Computers and Geotechnics, 2015, 65:147-163.
[21]	CAO X P, ZHU Y G, GONG J. Effect of the intermediate principal stress on the mechanical responses of binary granular mixtures with different fines contents[J/OL]. Granular Matter, 2021, 23(2)[2022-06-27]. https://doi.org/10.1007/s10035-021-01110-9.
[22]	ZHU Y G, NIE Z H, GONG J, et al. An analysis of the effects of the size ratio and fines content on the shear behaviors of binary mixtures using DEM[J/OL]. Computers and Geotechnics, 2020, 118[2022-06-27]. https://doi.org/10.1016/j.compgeo.2019.103353.
[23]	LOPEZ R D, SILFWERBRAND J, JELAGIN D, et al. Force transmission and soil fabric of binary granular mixtures[J]. Geotechnique, 2016, 66(7):578-583.
[24]	LINDQUIST E S. The strength and deformation properties of melange[D]. Berkeley:University of California at Berkeley, 1994.
[25]	李维树,丁秀丽,邬爱清,等.蓄水对三峡库区土石混合体直剪强度参数的弱化程度研究[J].岩土力学, 2007, 28(7):1338-1342.
[26]	XU W J, XU Q, HU R L. Study on the shear strength of soil-rock mixture by large scale direct shear test[J]. International Journal of Rock Mechanics and Mining Sciences, 2011, 48(8):1235-1247.
[27]	MINH N H, CHENG Y P, THORNTON C. Strong force networks in granular mixtures[J]. Granular Matter, 2014, 16(1):69-78.