Dilatancy analysis of granular materials based on mesoscopic topological evolutions

被引：0

作者：

Liu J. ^{[1
,2
,3
]}

Zhou W. ^{[4
]}

Ji X. ^{[5
]}

Wei G. ^{[1
,3
]}

Yuan S. ^{[1
]}

Li X. ^{[1
]}

机构：

[1] Department of Civil Engineering, Zhejiang University City College, Hangzhou

[2] Zhejiang Engineering Research Center of Intelligent Urban Infrastructre, Hangzhou

[3] Key Laboratory of Safe Construction and Intelligent Maintenance for Urban Shield Tunnels of Zhejiang Province, Hangzhou

[4] State Key Laboratory of Water Resources and Hydropower Engineering Science, Wuhan University, Wuhan

[5] Key Laboratory of Basin Water Security of Hubei Province, Changjiang Institute of Survey, Planning, Design and Research, Wuhan

来源：

Lixue Xuebao/Chinese Journal of Theoretical and Applied Mechanics | 2022年 / 54卷 / 03期

关键词：

Anisotropy; DEM; Dilatancy; Granular materials; Meso structure; Topological evolution;

D O I：

10.6052/0459-1879-21-521

中图分类号：

学科分类号：

摘要：

Dilatancy is one of the most important characteristics for frictional granular materials, especially for geo materials. It is widely accepted that the mechanism of dilatancy could be related to the evolution of the internal topological structure within the granular system. Based on meso-structural data of granular assemblies, features of the internal topological structure evolution in the granular system can be captured, which could further help to correlate the mesoscopic topological evolution and the macroscopic deformation properties including dilatancy. In this paper, the discrete element method (DEM) was used to conduct biaxial tests on dense, medium-dense and loose frictional granular materials, respectively. According to those DEM data from macroscopic to microscopic levels, the topological mechanism for dilatancy of granular materials are investigated in terms of network parameters (e.g., coordination number and clustering coefficient) and deformation features of 3 types of mesoscopic structures induced by topological exchanges. The results show that the significant strain softening and dilatancy occur for dense granular samples under biaxial loading, which is related to the topological and geometric changes of mesoscopic structures. The medium dense sample also exhibits dilatancy features but the degree is less evident, and the loose sample only shows contractancy and strain hardening during the shearing process. The contact network could be tessellated to force loop structures with the polygon shapes, and further classified into new, lost and constant categories by considering the topological exchanges. The anisotropy and composition evolutions of three groups of force loop structures are different, and loops with larger size could exhibit higher geometrical anisotropy. Under deviatoric loads, the new loop structures are easily related to higher dilatancy, and the dilatancy mechanism of the overall granular system could be influenced by the comprehensive effects of the topological evolutions of new meso structures and geometrical evolutions of constant meso structures. Copyright © 2022 Chinese Journal of Theoretical and Applied Mechanics. All rights reserved.

引用

页码：707 / 718

页数：11

共 49 条

[1] Sun Qicheng, Cheng Xiaohui, Ji Shunying, Et al., Advances in the micro-macro mechanics of granular soil materials, Advances in Mechanics, 41, 3, pp. 351-371, (2011)
[2] Yang Shuhan, Zhou Wei, Ma Gang, Et al., Mechanism of inter-particle friction effect on 3 D mechanical response of granular materials, Chinese Journal of Geotechnical Engineering, 42, 10, pp. 1885-1893, (2020)
[3] Chen Yunmin, Bian Xuecheng, The review of high-speed railway track foundation dynamics, China Civil Engineering Journal, 51, 6, pp. 1-13, (2018)
[4] Miu Linchang, Wang Zhengxing, Shi Wenbo, Theoretical and numerical simulations of face stability around shield tunnels in sand, Chinese Journal of Geotechnical Engineering, 37, 1, pp. 98-104, (2015)
[5] Yang Guanghua, Review of progress and prospect of modern constitutive theories for soils, Chinese Journal of Geotechnical Engineering, 40, 8, pp. 1363-1372, (2018)
[6] Chen Yunmin, Ma Pengcheng, Tang Yao, Constitutive models and hypergravity physical simulation of soils, Chinese Journal of Theoretical and Applied Mechanics, 524, pp. 901-915, (2020)
[7] Qu Tongming, Feng Yuntian, Wang Mengqi, Et al., Constitutive relations of granular materials by integrating micromechanical knowledge with deep learning, Chinese Journal of Theoretical and Applied Mechanics, 53, 7, pp. 1-12, (2021)
[8] Radjai F, Roux JN, Daouadji A., Modeling granular materials: century-long research across scales, Journal of Engineering Mechanics, 143, 4, (2017)
[9] Zhou Wei, Ma Gang, Liu Jiaying, Et al., Review of macro-and mesoscopic analysis on rockfill materials in high dams, Scientia Sinica Technologica, 48, 10, pp. 42-54, (2018)
[10] Lesniewska D, Nitka M, Tejchman J, Et al., Contact force network evolution in active earth pressure state of granular materials: photo-elastic tests and DEM, Granular Matter, 22, 3, pp. 1-31, (2020)

← 1 2 3 4 5 →