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原状及重塑黄土双轴试验微观力学特征离散元模拟

井旭 谢婉丽 单帅

井旭, 谢婉丽, 单帅. 原状及重塑黄土双轴试验微观力学特征离散元模拟[J]. 地质科技通报, 2021, 40(3): 184-193. doi: 10.19509/j.cnki.dzkq.2021.0311
引用本文: 井旭, 谢婉丽, 单帅. 原状及重塑黄土双轴试验微观力学特征离散元模拟[J]. 地质科技通报, 2021, 40(3): 184-193. doi: 10.19509/j.cnki.dzkq.2021.0311
Jing Xu, Xie Wanli, Shan Shuai. Discrete element simulation study on micromechanical characteristics of undisturbed and remolded loess in biaxial test[J]. Bulletin of Geological Science and Technology, 2021, 40(3): 184-193. doi: 10.19509/j.cnki.dzkq.2021.0311
Citation: Jing Xu, Xie Wanli, Shan Shuai. Discrete element simulation study on micromechanical characteristics of undisturbed and remolded loess in biaxial test[J]. Bulletin of Geological Science and Technology, 2021, 40(3): 184-193. doi: 10.19509/j.cnki.dzkq.2021.0311

原状及重塑黄土双轴试验微观力学特征离散元模拟

doi: 10.19509/j.cnki.dzkq.2021.0311
基金项目: 

陕西省国际科技合作与交流计划重点项目 2019KWZ-02

国家自然科学面上基金 4197020993

国家重点研发课题 2017YFD0800501

国家自然科学基金资助项目 41772323

详细信息
    作者简介:

    井旭(1995-), 男, 现正攻读地质工程专业硕士学位, 主要从事岩土工程数值模拟研究工作。E-mail: jingxu@cug.edu.cn

    通讯作者:

    谢婉丽(1974-), 女, 教授, 主要从事地质灾害治理、黄土微观结构方面的研究工作。E-mail: xiewanli@nwu.edu.cn

  • 中图分类号: P511

Discrete element simulation study on micromechanical characteristics of undisturbed and remolded loess in biaxial test

  • 摘要: 黄土作为一种特殊的颗粒材料,微观上颗粒组成的结构决定了其力学特性。原状及重塑黄土因结构的差异而具有不同的力学特性。针对黄土结构性如何影响其力学特征这一基本问题,开展基于电镜扫描获取细观颗粒信息,同时考虑颗粒形状、颗粒破碎可能性进行建模的离散单元法进行原状黄土和饱和重塑土在恒定应变速率双轴试验下的宏观力学和细观力学性能研究。研究结果显示:试样微观结构的差异对变形破坏过程产生显著影响。当轴向应力较低时原状黄土及重塑黄土力链多分布于大型骨架颗粒附近,随着轴向应力增加,原状黄土力链形成网状图案但仍具备主要传导区域,重塑黄土无明显主要传导区,呈现均匀网状。原状土及重塑土骨架颗粒簇周围多形成张拉裂隙,剪切裂隙多数形成于骨架颗粒簇内部,又以颗粒簇相互挤压接触时最为明显。使用该建模方法,可以有效反映原状及重塑黄土由于内部结构组成差异导致相同应力条件下产生的不同内部应力状态。基于以上研究结论,给出了黄土结构性对宏观强度影响的微观解释。研究成果可为黄土地区地质灾害防治提供一定依据。使用该建模方法,可以有效反映原状及重塑黄土由于内部结构组成差异导致相同应力条件下产生的不同内部应力状态。基于以上研究结论,给出了黄土结构性对宏观强度影响的微观解释。

     

  • 图 1  三轴试验后试样照片

    a.原状样;b.重塑样

    Figure 1.  Sample picture after triaxial test

    图 2  黄土微结构特征及分布

    a.原状黄土; b.重塑黄土

    Figure 2.  Microstructure characteristics and distribution of loess

    图 3  最大及最小费雷特直径示意图

    Figure 3.  Schematic diagram of the maximum and minimum Feret diameters

    图 4  黏结模型示意图

    a.平行黏结b.接触黏结

    Figure 4.  Schematic diagram of bonding model

    图 5  试样离散元建模

    a.原状黄土离散元模型; b.重塑黄土离散元模型

    Figure 5.  Sample discrete element modeling

    图 6  双轴试验示意图

    Figure 6.  Schematic diagram of biaxial test

    图 7  PFC材料不同围压下应力-应变曲线

    Figure 7.  Stress-strain curves of PFC material under different confining pressures

    图 8  原状黄土力链图

    Figure 8.  Undisturbed loess force chain diagram

    a.σ3=50 kPa; b.σ3=100 kPa; c.σ3=200 kPa; d.σ3=400 kPa

    图 9  重塑黄土力链图

    Figure 9.  Remolded loess force chain diagram

    a.σ3=50 kPa; b.σ3=100 kPa; c.σ3=200 kPa; d.σ3=400 kPa

    图 10  原状黄土剪切裂隙分布图

    Figure 10.  Distribution map of undisturbed loess shear cracks

    a.σ3=50 kPa; b.σ3=100 kPa; c.σ3=200 kPa; d.σ3=400kPa

    图 11  重塑黄土剪切裂隙分布图

    Figure 11.  Distribution map of shear cracks in remolded loess

    a.σ3=50 kPa; b.σ3=100 kPa; c.σ3=200 kPa; d.σ3=400kPa

    图 12  原状黄土拉张裂隙分布图

    Figure 12.  Distribution of tensile fissures in undisturbed loess

    a.σ3=50 kPa; b.σ3=100 kPa; c.σ3=200 kPa; d.σ3=400 kPa

    图 13  重塑黄土拉张裂隙分布图

    Figure 13.  Distribution map of tensile cracks in remolded loess

    a.σ3=50 kPa; b.σ3=100 kPa; c.σ3=200 kPa; d.σ3=400 kPa

    图 14  原状黄土裂隙数量变化曲线

    Figure 14.  Curve of the number of cracks in undisturbed

    图 15  重塑黄土裂隙数量变化曲线

    Figure 15.  Curve of the number of cracks in remolded

    表  1  土体宏观力学参数

    Table  1.   Macroscopic mechanical parameters of loess

    密度ρ/(g·cm-3) 孔隙比e 黏聚力c/
    kPa
    内摩擦角φ/(°)
    原状土 1.62 0.85 55.8 15.9
    重塑土 1.62 0.81 39.3 8.8
    下载: 导出CSV

    表  2  PFC模型细观参数

    Table  2.   Micro-parameters of PFC model

    土样 参数 几何颗粒 球颗粒 几何-球 碎屑及团粒
    原状土 法向刚度/(N·m-1) 1.5×1010 1.5×1010 1.5×1010 -
    剪切刚度/(N·m-1) 1.0×1010 1.0×1010 1.0×1010 -
    有效模量/(N·m-2) 2.0×107 2.0×107 2.0×107 -
    刚度比 1.0 1.0 1.0 -
    平行黏结有效模量/(N·m-2) 2.0×107 2.0×107 2.0×107 -
    平行黏结刚度比 1.0 1.0 1.0 -
    颗粒摩擦系数 0.5 0.5 0.5 -
    法向黏结刚度/(N·m-1) 1.5×106 8.0×105 8.0×105 -
    切向黏结刚度/(N·m-1) 1.5×106 1.5×1010 8.0×105 -
    黏结力/(N·m-1) 3.5×105 1.3×105 1.3×105 -
    重塑土 法向刚度/(N·m-1) 1.5×1010 1.5×1010 1.5×1010 1.5×1010
    剪切刚度/(N·m-1) 1.0×1010 1.0×1010 1.0×1010 1.0×1010
    有效模量/N·m-2) 2.0×107 2.0×107 2.0×107 2.0×107
    刚度比 1.0 1.0 1.0
    平行黏结有效模量/(N·m-2) 2×107 - 2×107 2×107
    平行黏结刚度比 1.0 - 1.0 1.0
    颗粒摩擦系数 0.5 0.5 0.5 0.5
    法向黏结刚度/(N·m-1) 1.4×106 6.0×106 6.9×105 6.9×105
    切向黏结刚度/(N·m-1) 1.4×106 6.0×106 6.9×105 6.9×105
    黏结力/(N·m-1) 3.0×105 - 1.5×105 1.5×105
    下载: 导出CSV
  • [1] 任晓虎, 许强, 赵宽耀, 等. 反复入渗对重塑黄土渗透特性的影响[J]. 地质科技通报, 2020, 39(2): 130-138. http://dzkjqb.cug.edu.cn/CN/abstract/abstract9982.shtml

    Ren X H, Xu Q, Zhao K Y, et al. Effect of repeated infiltration on permeability characteristics of remolded loess[J]. Bulletin of Geological Science and Technology, 2020, 39(2): 130-138(in Chinese with English abstract). http://dzkjqb.cug.edu.cn/CN/abstract/abstract9982.shtml
    [2] 刘博诗, 张延杰, 王旭, 等. 人工制备黄土湿陷性影响因素及微观机理研究[J]. 地下空间与工程学报, 2017, 13(2): 330-336, 343. https://www.cnki.com.cn/Article/CJFDTOTAL-BASE201702007.htm

    Liu B S, Zhang Y J, Wang X, et al. Research on the collapsibility influencing factors and micro-mechanism of artificial loess[J]. Chinese Journal of Underground Space and Engineering, 2017, 13(2): 330-336, 343(in Chinese with English abstract). https://www.cnki.com.cn/Article/CJFDTOTAL-BASE201702007.htm
    [3] Wan L X, Ping L, Sai K, et al. Prediction of the wetting-induced collapse behaviour using the soil-water characteristic curve[J]. Journal of Asian Earth Sciences, 2018, 151: 259-268. doi: 10.1016/j.jseaes.2017.11.009
    [4] 董吉, 陈筠, 邬忠虎, 等. 木质素纤维红黏土强度及变形特性试验研究[J]. 地质力学学报, 2019, 25(3): 421-427. https://www.cnki.com.cn/Article/CJFDTOTAL-DZLX201903009.htm

    Dong J, Chen Y, Wu Z H, et al. Experimental study on the shear strength and deformation characteristics of lignin-fiber red clay[J]. Chinese Journal of Geomechanics, 2019, 25(3): 421-427(in Chinese with English abstract). https://www.cnki.com.cn/Article/CJFDTOTAL-DZLX201903009.htm
    [5] 张炜, 周剑, 于世伟, 等. 双轴压缩下颗粒物质接触力与力链特性研究[J]. 应用力学学报, 2018, 35(3): 530-537, 687. https://www.cnki.com.cn/Article/CJFDTOTAL-YYLX201803014.htm

    Zhang W, Zhou J, Yu S W, et al. Research on contact force and force chain characteristics of particulate matter under biaxial compression[J]. Chinese Journal of Applied Mechanics, 2018, 35(3): 530-537, 687(in Chinese with English abstract). https://www.cnki.com.cn/Article/CJFDTOTAL-YYLX201803014.htm
    [6] Bock H, Blümling P, Konietzky H. Study of the micro-mechanical behaviour of the Opalinus Clay: An example of co-operation across the ground engineering disciplines[J]. Bulletin of Engineering Geology and the Environment, 2006, 65(2): 195-207. doi: 10.1007/s10064-005-0019-9
    [7] 李识博, 王常明, 王念秦, 等. 黄土三轴试验的颗粒流数值模拟[J]. 中国公路学报, 2013, 26(6): 22-29. doi: 10.3969/j.issn.1001-7372.2013.06.004

    Li S B, Wang C M, Wang N Q, et al. Numerical simulation of loess triaxial shear test by PFC3D[J]. China Journal of Highway and Transport, 2013, 26(6): 22-29(in Chinese with English abstract). doi: 10.3969/j.issn.1001-7372.2013.06.004
    [8] 张崇帅. 考虑球体颗粒胶结的三维颗粒流模拟研究[D]. 西安: 西安理工大学, 2018.

    Zhang C S. PFC3D simulation study considering spherical particle cementation[D]. Xi'an: Xi'an University of Technology, 2018(in Chinese with English abstract).
    [9] 宁孝梁. 黏性土的细观三轴模拟与微观结构研究[D]. 杭州: 浙江大学, 2017.

    Ning X L. The meso-simulation of triaxial tests and microstructure study of the cohesive soil[D]. Hangzhou: Zhejiang University, 2017(in Chinese with English abstract).
    [10] 崔博, 邓博麒, 刘明辉, 等. 基于不规则颗粒离散元的砾石土三轴数值模拟[J]. 水力发电学报, 2020, 39(4): 73-87. https://www.cnki.com.cn/Article/CJFDTOTAL-SFXB202004008.htm

    Cui B, Deng B Q, Liu M H, et al. Numerical simulation of triaxial tests on gravelly soil based on DEM of irregular-shaped particles[J]. Journal of Hydroelectric Engineering, 2020, 39(4): 73-87(in Chinese with English abstract). https://www.cnki.com.cn/Article/CJFDTOTAL-SFXB202004008.htm
    [11] 焦玉勇, 王浩, 马江锋. 土石混合体力学特性的颗粒离散元双轴试验模拟研究[J]. 岩石力学与工程学报, 2015, 34(增刊1): 3564-3573. https://www.cnki.com.cn/Article/CJFDTOTAL-YSLX2015S1118.htm

    Jiao Y Y, Wang H, Ma J F. Research on biaxial test of mechanical characteristics on soil-rock aggregate(SRA) based on particle flow code simulation[J]. Chinese Journal of Rock Mechanics and Engineering, 2015, 34(S1): 3564-3573(in Chinese with English abstract). https://www.cnki.com.cn/Article/CJFDTOTAL-YSLX2015S1118.htm
    [12] 周伦伦. 颗粒破碎与形状对颗粒材料力学性质影响的离散元研究[D]. 武汉: 武汉大学, 2017.

    Zhou L L. DEM investigation of influence of particle breakage and shape on the mechanical behaviors of granular materials[D]. Wuhan: Wuhan University, 2017(in Chinese with English abstract).
    [13] Wensrich C M, Katterfeld A, Sugo D. Characterisation of the effects of particle shape using a normalised contact eccentricity[J]. Granular Matter, 2014, 16(3): 327-337. doi: 10.1007/s10035-013-0465-1
    [14] 闫欣宜, 胡新丽, 付茹. 橡胶纤维-砂混合料力学特性的离散元三轴试验研究[J]. 地质科技通报, 2020, 39(2): 168-174. http://dzkjqb.cug.edu.cn/CN/abstract/abstract9986.shtml

    Yan X Y, Hu X L, Fu R. Triaxial shear test of mechanical characteristics on rubber fiber-sand mixtures based on particle flow code simulation[J]. Bulletin of Geological Science and Technology, 2020, 39(2): 168-174(in Chinese with English abstract). http://dzkjqb.cug.edu.cn/CN/abstract/abstract9986.shtml
    [15] Estrada N, E Azéma, Radjai F, et al. Identification of rolling resistance as a shape parameter in sheared granular media[J]. Physical Review E, 2011, 84(1): 11306-11306. doi: 10.1103/PhysRevE.84.011306
    [16] 林成远, 唐辉明, 汪丁建, 等. 块石定向性特征对土-石混合体强度影响的数值模拟[J]. 地质科技通报, 2020, 39(5): 38-46. http://dzkjqb.cug.edu.cn/CN/abstract/abstract10048.shtml

    Lin C Y, Tang H M, Wang D J, et al. Influence on the strength of soil-rock mixture made by the rock block orientation features based on numerical experiment[J]. Bulletin of Geological Science and Technology, 2020, 39(5): 38-46(in Chinese with English abstract). http://dzkjqb.cug.edu.cn/CN/abstract/abstract10048.shtml
    [17] Liu S H, Wang Y S, Shen C M. DEM analysis of granular crushing during simple shearing[J]. Marine Georesources & Geotechnology, 2018, 36(5): 522-531. https://www.researchgate.net/profile/Sihong-Liu-2/publication/319222548_DEM_analysis_of_granular_crushing_during_simple_shearing/links/5e87ea47299bf13079786fb0/DEM-analysis-of-granular-crushing-during-simple-shearing.pdf
    [18] 李长冬, 唐辉明, 胡新丽, 等. 岩石相似材料变形与强度特性及数值模拟研究[J]. 地质科技情报, 2008, 27(6): 98-101. doi: 10.3969/j.issn.1000-7849.2008.06.019

    Li C D, Tang H M, Hu X L, et al. Deformation and strength characteristics and numerical simulation of rock similar material[J]. Geological Science and Technology Information, 2008, 27(6): 98-101(in Chinese with English abstract). doi: 10.3969/j.issn.1000-7849.2008.06.019
    [19] 陈璞皎, 郑祥民, 周立旻, 等. 宁镇地区下蜀黄土粒度特征及其古环境意义[J]. 地质科技情报, 2017, 36(5): 7-13. https://www.cnki.com.cn/Article/CJFDTOTAL-DZKQ201705002.htm

    Chen P J, Zheng X M, Zhou L M, et al. Grain size distribution and its significance of the Xiashu loess in Nanjing-Zhenjiang area[J]. Geological Science and Technology Information, 2017, 36(5): 7-13(in Chinese with English abstract). https://www.cnki.com.cn/Article/CJFDTOTAL-DZKQ201705002.htm
    [20] Wang Y, Yang H, Jing X. Structural characteristics of natural loess in northwest China and its effect on shear behavior[J]. Geotechnical and Geological Engineering, 2020, 39(1): 65-78. doi: 10.1007/s10706-020-01608-8
    [21] Jiang M, Zhang F, Hu H. DEM Modeling Mechanical Behavior of Unsaturated Structural Loess under Constant Stress Increment Ratio Compression Tests[J]. International Journal of Geomechanics, 2017, 17(4): 04016108. doi: 10.1061/(ASCE)GM.1943-5622.0000762
    [22] Shi D D, Zheng L, Xue J F, et al. DEM modeling of particle breakage in silica sands under one-dimensional compression[J]. Acta Mechanica Solida Sinica, 2016, 29(1): 78-94. doi: 10.1016/S0894-9166(16)60008-3
    [23] Ueda T, Matsushima T, Yamada Y. DEM simulation on the one-dimensional compression behavior of various shaped crushable granular materials[J]. Granular Matter, 2013, 15(5): 675-684. doi: 10.1007/s10035-013-0415-y
    [24] 罗勇. 土工问题的颗粒流数值模拟及应用研究[D]. 杭州: 浙江大学, 2007.

    Luo Y. Simulation of soil mechanical behaviors using discrete element method based on particle flow code and it application[D]. Hangzhou: Zhejiang University, 2007(in Chinese with English abstract).
    [25] 张刚, 周健, 姚志雄. 堤坝管涌的室内试验与颗粒流细观模拟研究[J]. 水文地质工程地质, 2007, 34(6): 83-86. doi: 10.3969/j.issn.1000-3665.2007.06.020

    Zhang G, Zhou J, Yao Z X. Study on mesomechanical simulation of piping with model tests and PFC2D[J]. Hydrogeology and Engineering Geology, 2007, 34(6): 83-86(in Chinese with English abstract). doi: 10.3969/j.issn.1000-3665.2007.06.020
    [26] 姚志雄, 周健, 张刚. 砂土管涌机理的细观试验研究[J]. 岩土力学, 2009, 30(6): 1604-1610. doi: 10.3969/j.issn.1000-7598.2009.06.012

    Yao Z X, Zhou J, Zhang G. Meso-experimental research on piping mechanism in sandy soils[J]. Rock and Soil Mechanics, 2009, 30(6): 1604-1610(in Chinese with English abstract). doi: 10.3969/j.issn.1000-7598.2009.06.012
    [27] Li T, Jiang M M, Colin T. Three-dimensional discrete element analysis of triaxial tests and wetting tests on unsaturated compacted silt[J]. Computers and Geotechnics, 2018, 97: 90-102. doi: 10.1016/j.compgeo.2017.12.011
    [28] 同霄, 朱兴华, 马鹏辉, 等. 颗粒离散元方法中黄土强度参数研究[J]. 地下空间与工程学报, 2019, 15(2): 435-442. https://www.cnki.com.cn/Article/CJFDTOTAL-BASE201902018.htm

    Tong X, Zhu X H, Ma P H, et al. Study on the strength parameters of loess in granular discrete element method[J]. Chinese Journal of Underground Space and Engineering, 2019, 15(2): 435-442(in Chinese with English abstract). https://www.cnki.com.cn/Article/CJFDTOTAL-BASE201902018.htm
    [29] Owen D R J, Feng Y T. Parallelised finite/discrete element simulation of multi-fracturing solids and discrete systems[J]. Engineering Computations 2001, 18(3/4): 557-576. doi: 10.1108/02644400110387154
    [30] 蒋明镜, 李涛, 胡海军. 结构性黄土双轴压缩试验的离散元数值仿真分析[J]. 岩土工程学报, 2013, 35(增刊2): 241-246. https://www.cnki.com.cn/Article/CJFDTOTAL-YTGC2013S2041.htm

    Jiang M J, Li T, Hu H J. Numerical simulation of biaxial tests on structured loess by distinct element method[J]. Chinese Journal of Geotechnical Engineering, 2013, 35(S2): 241-246(in Chinese with English abstract). https://www.cnki.com.cn/Article/CJFDTOTAL-YTGC2013S2041.htm
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