Characteristics and Numerical Simulation of the Failure Process ofIntercalated Shear Zone under Dam Foundation in Red Bed

NIE Qiong; XIANG Wei

doi:10.3969/j.issn.1001-5485.2014.06.0112014, 31(06):53-59

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Journal of Changjiang River Scientific Research Institute ›› 2014, Vol. 31 ›› Issue (6) : 53-59. DOI: 10.3969/j.issn.1001-5485.2014.06.0112014, 31(06):53-59

ROCK-SOIL ENGINEERING

Characteristics and Numerical Simulation of the Failure Process ofIntercalated Shear Zone under Dam Foundation in Red Bed

NIE Qiong¹, XIANG Wei^{1, 2}

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Abstract

The depositional environment of the bedrock of Xiaonanhai Dam is dominated by floodplain sub-facies. The strata are mainly composed of siltstone and mudstone interbedded. Tectonic leads to the buckling of layers, and groundwater causes the softening and mudding of wear intercalation. Those are three essential factors for the formation of intercalated shear zone in the alternatively distributed soft and hard rock layers. The macro-properties of shear zone can be simulated in mesomechanical level by particle flow code (PFC). On the basis of particle flow theory, PFC^2D models of shear zone were established to study its shear failure process, in which different contact bond constitutive relations were introduced. The simulation test focused on the void ratio change, as well as the position, width, angle and spacing of the shear cracks. Results show that the shear failure process of the model is consistent with the development of slip surface in clay which was proposed by A.W. Skempton. Eight PFC^2D models of shear zone samples with different thicknesses and lengths were compared, and the simulation results reveal that when the thickness of hard and soft rock is fixed, the longer sample leads to the gentler angle of the cracks and larger spacing between them. Meanwhile, micro-cracks are prone to be concentrated initially in both ends of the shear zone. Maintaining the length and the thickness of hard rock, the spacing of the cracks becomes larger with the increasing thickness of shear zone, but the angle remains unchanged.

Key words

red bed / intercalated shear zone / particle flow code / mesomechanics / shear failure

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NIE Qiong, XIANG Wei. Characteristics and Numerical Simulation of the Failure Process ofIntercalated Shear Zone under Dam Foundation in Red Bed[J]. Journal of Changjiang River Scientific Research Institute. 2014, 31(6): 53-59 https://doi.org/10.3969/j.issn.1001-5485.2014.06.0112014, 31(06):53-59

References

[1] 王子忠. 四川盆地红层岩体主要水利水电工程地质问题系统研究[D]. 成都: 成都理工大学, 2011.(WANG Zi-zhong. Systematic Researches on Red Bed Rock Mass Engineering Geological Problems of Water Resources and Hydropower Projects in Sichuan Basin, China[D]. Chengdu: Chengdu University of Technology, 2011.(in Chinese))
[2] 徐瑞春, 周建军. 红层与大坝[M]. 武汉:中国地质大学出版社, 2010. (XU Rui-chun, ZHOU Jian-jun. Red Bed and Dam[M]. Wuhan: China University of Geosciences Press, 2010. (in Chinese))
[3] 胡涛, 任光明, 聂德新, 等. 沉积型软弱夹层成因分类及强度特征[J]. 中国地质灾害与防治学报, 2004, 15(1): 124-128.(HU Tao, REN Guang-ming, NIE De-xin, et al. Strength Characteristics with Genesis and Type of the Sedimentary Weak Intercalated Layers[J]. The Chinese Journal of Geological Hazard and Control, 2004, 15(1): 124-128. (in Chinese))
[4] 李守定, 李晓, 常年学, 等. 三峡库区侏罗系易滑地层沉积特征及其对岩石物理力学性质的影响[J]. 工程地质学报, 2004, 12(4): 385-389. (LI Shou-ding, LI Xiao, CHANG Nian-xue, et al. Sedimentation Characteristics of the Jurassic Sliding Prone Stratum in the Three Gorges Reservoir Area and Their Influence on Physical and Mechanical Properties of Rock[J]. Journal of Engineering Geology, 2004, 12(4): 385-389. (in Chinese))
[5] 谭罗荣. 葛洲坝泥化夹层的物质组成特性[J]. 岩土力学, 1984, 5(2): 27-34. (TAN Luo-rong. The Behavior of Weak Intercalations Compositions of Matter at Gezhouba Dam[J]. Rock and Soil Mechanics, 1984, 5(2): 27-34. (in Chinese))
[6] 项伟. 软弱夹层微结构研究及其力学意义[J]. 地球科学-武汉地质学院学报, 1985, 10(1): 165-169. (XIANG Wei. The Study of Microstructures of Weak Intercalations and Their Mechanical Significance[J]. Earth Science:Journal of Wuhan College of Geology, 1985, 10(1): 165-169. (in Chinese))
[7] SKEMPRON A W. Some Observations on Tectonic Shear Zones[C]∥Proceedings of the 1st ISRM Congress, Lisbon, Portugal, September 25-October 1, 1966.
[8] 孙万和, 杨连生, 慎乃齐, 等. 葛洲坝坝基层间剪切带的模拟研究[J]. 武汉水利电力学院学报, 1991, 24(5):495-502. (SUN Wan-he, YANG Lian-sheng, SHEN Nai-qi, et al. Model Study of Intercalated Shear Zone in Gezhouba Dam Foundation[J]. Journal of Wuhan University of Hydraulic and Electric Engineering, 1991, 24(5):495-502. (in Chinese))
[9] 周健, 池毓蔚, 池永, 等. 双轴试验的颗粒流模拟[J]. 岩土工程学报, 2000, (6):701-704.(ZHOU Jian, CHI Yu-wei, CHI Yong, et al. Simulation of Biaxial Test on Sand by Particle Flow Code[J]. Chinese Journal of Geotechnical Engineering, 2000, (6):701-704. (in Chinese))
[10]廖雄华, 周健, 徐建平, 等. 黏性土室内平面应变试验的颗粒流模拟[J]. 水利学报, 2002, (12):11-17. (LIAO Xiong-hua, ZHOU Jian, XU Jian-ping, et al. Simulation of Plane Strain Test of Clay by Means of Particle Flow Code[J]. Journal of Hydraulic Engineering, 2002, (12):11-17. (in Chinese))
[11]周健, 池永. 砂土力学性质的细观模拟[J]. 岩土力学, 2003, (6):901-906. (ZHOU Jian, CHI Yong. Mesomechanical Simulation of Sand Mechanical Properties[J]. Rock and Soil Mechanics, 2003, (6):901-906. (in Chinese))
[12]蒋明镜, 李秀梅. 双轴压缩试验中砂土剪切带形成的离散元模拟分析[J]. 山东大学学报(工学版), 2010, 40(2):52-58. (JIANG Ming-jing, LI Xiu-mei. DEM Simulation of the Shear Band of Sands in Biaxial Test[J]. Journal of Shandong University (Engineering Science), 2010, 40(2):52-58. (in Chinese))
[13]JIANG M J, YAN H B, ZHU H H, et al. Modeling Shear Behavior and Strain Localization in Cemented Sand by Two-dimensional Distinct Element Method Analyses[J]. Computers and Geotechnics, 2010, 38(1):14-29.
[14]UTILI S, OVA R. DEM Analysis of Bonded Granular Geomaterials[J]. Journal for Numerical and Analytical Methods in Geomechanics, 2008, (32): 1997-2031.
[15]蔡正银. 砂土的渐进破坏及其数值模拟[J]. 岩土力学, 2008, 29(3):580-585. (CAI Zheng-yin. Progressive Failure of Sand and Its Numerical Simulation[J]. Rock and Soil Mechanics, 2008, 29(3): 580-585. (in Chinese))
[16]蔡正银, 李相崧. 无黏性土中剪切带的形成过程[J]. 岩土工程学报, 2003, (2):129-134. (CAI Zheng-yin, LI Xiang-song. Formation of Shear Band in Cohesionless Soils[J]. Chinese Journal of Geotechnical Engineering, 2003, (2):129-134. (in Chinese))
[17]张晓平, 吴顺川, 张志增, 等. 含软弱夹层土样变形破坏过程细观数值模拟及分析[J]. 岩土力学, 2008, 29(5):1200-1209. (ZHANG Xiao-ping, WU Shun-chuan, ZHANG Zhi-zeng, et al. Numerical Simulation and Analysis of Failure Process of Soil with Weak Intercalated Layer[J]. Rock and Soil Mechanics, 2008, 29(5):1200-1209. (in Chinese))
[18]吴顺川, 张晓平, 刘洋. 基于颗粒元模拟的含软弱夹层类土质边坡变形破坏过程分析[J]. 岩土力学, 2008, 29(11):2899-2904. (WU Shun-chuan, ZHANG Xiao-ping, LIU Yang. Analysis of Failure Process of Similar Soil Slope with Weak Intercalated Layer Based on Particle Flow Simulation[J]. Rock and Soil Mechanics, 2008, 29(11):2899-2904. (in Chinese))
[19]四川省地质矿产局. 四川省区域地质志[M]. 北京: 地质出版社, 1991:159-260. (Sichuan Provincial Bureau of Geology and Mineral Resources. Sichuan Province Regional Geology[M]. Beijing: Geology Press, 1991:159-260. (in Chinese))
[20]YE Ming, KHALEEL R. A Markov Chain Model for Characterizing Medium Heterogeneity and Sediment Layering Structure[J]. Water Resources Research, 2008, 44(9):1-15.
[21]ITASCA Consulting Group. PFC^2D (Particle Flow Code in 2 Dimensions) Theory and Background[M]. USA: Itasca Consulting Group, Minneapolis, Minnesota, 2002.
[22]吴自强, 朱祚铎. 岩石剪切破裂中的“Riedel Shear”构造模式[J]. 岩土力学, 1991, 12 (2):67-74. (WU Zi-qiang, ZHU Zuo-duo. The “Riedel Shear” Structure Mode Concerning the Shearing Failure of Rocks[J]. Rock and Soil Mechanics, 1991, 12 (2):67-74. (in Chinese))