不同三维应力路径下超固结黏土变形局部化

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摘要利用非线性有限元软件 ABAQUS 材料子程序接口，采用回映应力更新算法，实现了基于改进伏斯列夫面超固结黏土三维本构模型在有限元分析中的应用。通过该模型与比奥固结理论的耦合，对超固结比为 8 的藤森黏土在三轴压缩、三轴伸长及平面应变时的变形局部化问题，进行了三维应力状态下的土水耦合弹塑性分析。分析结果表明：剪切带带内、带外点经历了大致相同的应力路径；剪切带带外单元体变经历了体缩，而剪切带带内单元一直保持剪胀趋势；剪切带的形成伴随着剪胀，剪切带内外出现了负的孔压，且孔压的分布也具有局部化特性。关于剪切带带内、带外的孔隙水压及体积变化趋势，平面应变介于三轴压缩与三轴伸长之间，但平面应变较早出现剪切带。

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	孙德安
	陈立文
	甄文战

关键词 ：超固结黏土, 孔压, 剪胀, 三维应力, 剪切带

Abstract：An improved Hvorslev envelope-based three-dimensional elastoplastic constitutive model was proposed by Yao et al. (2008) for overconsolidated clays. The return mapping algorithm is adopted in order to implement the constitutive model into a finite element analysis software ABAQUS through the user material subroutine interface. By coupling the model with the Biot’s consolidation theory, coupled analyses of the localized deformation on overconsolidated clay specimens under undrained boundary conditions in triaxial compression and extension and plane strain stress states are performed. The numerical results show that the same stress paths are seen for the elements inside and outside the shear band. The elements in the vicinities of the shear band behave volume contracted, while the elements inside the shear band keep shear dilatancy during shear. The shear dilatancy is accompanied by the development of the shear band, and negative pore pressure appears inside the shear band and their vicinities. The changes in the pore water pressure and volumetric strain in the plane strain are between triaxial compression and extension stresses, but shear bands early occur in the plane strain.

Key words： overconsolidated clay pore pressure dilatancy three-dimensional stress shear band

收稿日期: 2011-04-29

TU443

作者简介: 孙德安 (1962 – ) ，男，浙江余姚人，博士，教授，博士生导师，主要从事非饱和土力学、土的基本性质及其本构理论等方面的研究与教学工作。

引用本文:

孙德安, 陈立文, 甄文战. 不同三维应力路径下超固结黏土变形局部化[J]. 岩土工程学报, 2011, 33(zk1): 39-44. SUN De-an, CHEN Li-wen, ZHEN Wen-zhan. Strain localization of overconsolidated clay under different three-dimensional stress paths. Chinese J. Geot. Eng., 2011, 33(zk1): 39-44.

链接本文:

http://manu31.magtech.com.cn/Jwk_ytgcxb/CN/ 或 http://manu31.magtech.com.cn/Jwk_ytgcxb/CN/Y2011/V33/Izk1/39

[1] 李蓓 , 赵锡宏 , 董建国 . 上海黏土剪切带倾角的试验研究 [J]. 岩土力学 , 2002, 23 (4): 423 – 427. (LI Bei, ZHAO Xi-hong, DONG Jian-guo. Experimental study on shear band inclination in Shanghai clay[J]. Rock and Soil Mechanics, 2002, 23 (4): 423 – 427. (in Chinese))
[2] WANG Q, LADE P V. Shear banding in true triaxial tests and its effect on failure in sand[J]. Journal of Engineering Mechanics, ASCE, 2001, 127 (8): 754 – 761.
[3] 钱建固 , 黄茂松 . 土体变形分叉的非共轴理论 [J]. 岩土工程学报 , 2004, 26 (6): 777 – 781. (QIAN Jian-gu, HUANG Mao-song. Non-coaxiality for deformation bifurcation in soils[J]. Chinese Journal of Geotechnical Engineering, 2007, 26 (2): 465 – 471. (in Chinese))
[4] 甄文战 , 孙德安 , 段博 . 超固结土本构模型分叉三维理论分析及数值模拟 [J]. 岩土工程学报 , 2010, 32 (12): 1921 – 1926. (ZHEN Wen-zhan, SUN De-an, DUAN Bo. Theoretical analysis and numerical simulation of three-dimensional bifurcation by constitutive model for over-consolidated clays [J]. Chinese Journal of Geotechnical Engineering, 2010, 32 (12): 1921 – 1926. (in Chinese))
[5] HUANG W X, SUN D A, SLOAN S W. Analysis of the failure mode and softening behaviour of sands in true triaxial tests[J]. International Journal of Solids and Structures, 2007, 44 (5): 1423 – 1437.
[6] 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))
[7] 徐连民 , 王兴然 . 用有限变形理论研究黏性土试样中变形的局部化问题 [J]. 岩土工程学报 , 2004, 26 (2): 125 – 129. (XU Lian-min, WANG Xing-ran. Numerical simulation of shear band in clayey soils using finite deformation theory[J]. Chinese Journal of Geotechnical Engineering, 2004, 26 (2): 125 – 129. (in Chinese))
[8] 甄文战 , 孙德安 , 段博 . 不同应力路径下超固结黏土试样变形局部化分析 [J]. 岩土力学 , 2011, 32 (1): 293 – 298. (ZHEN Wen-zhan, SUN De-an, DUAN Bo. Analysis of strain localization in overconsolidated clay specimens along different stress paths[J]. Rock and Soil Mechanics, 2011, 32 (1): 293 – 298. (in Chinese))
[9] 姚仰平 , 李自强 , 侯伟 , 等 . 基于改进伏斯列夫线的超固结土本构模型 [J]. 水利学报 , 2008, 39 (11): 1244 – 1250. (YAO Yang-ping, LI Zi-qiang, HOU Wei, et al. Constitutive model of over-consolidated clay based on improved Hvorslev envelope[J]. Journal of Hydraulic Engineering, 2008, 39 (11): 1244 – 1250. (in Chinese))
[10] YAO Y P, HOU W, ZHOU A N. UH model: three-dimensional unified hardening model for overconsolidated clays[J]. Géotechnique, 2009, 59 (5): 451 – 469.
[11] 孙德安 , 甄文战 . 不同应力路径下剪切带的数值模拟 [J]. 岩土力学 , 2010, 31 (7): 2253 – 2258. (SUN De-an, ZHEN Wen-zhen. Numerical simulation of shear bands along different stress paths[J]. Rock and Soil Mechanics, 2010, 31 (7): 2253 – 2258. (in Chinese) )