|
|
|
| MODIFIED CAM-CLAY MODEL CONSIDERING COHESION AND S-D EFFECT AND ITS NUMERICAL IMPLEMENTATION |
| YUAN Kekuo1，CHEN Weizhong1，2，YU Hongdan1，TAN Xianjun1，ZHAO Wusheng1，LI Xiangling3 |
| (1. State Key Laboratory of Geomechanics and Geotechnical Engineering，Institute of Rock and Soil Mechanics，Chinese Academy of Sciences，Wuhan，Hubei 430071，China；2. Geotechnical and Structural Engineering Research Center，Shandong University，Jinan，Shandong 250061，China；3. Euridice，SCK•CEN，Belgian Nuclear Research Centre，Mol 2400，Belgium) |
|
|
|
|
Abstract Due to the conventional modified Cam-clay model can not describe the cohesion properties and different yield strengths in tension and compression performance (S-D effect for short) for geotechnical materials，a modified Cam-clay model with non-associated flow rule is established considering S-D effect on deviatoric plane and cohesion on meridian plane. The main contents of implicit constitutive integration algorithm for the improved model and its implementation procedure are discussed systematically. Based on the platform of software ABAQUS，the user-defined material subroutine UMAT interface is developed to generate corresponding constitutive subroutine of the modified Cam-clay model. Meanwhile，the numerical simulation of triaxial compression test on Belgium Boom clay is implemented. The study result shows that the improved constitutive model and the UMAT subroutine have higher calculation accuracy and good stability，which could effectively depict the nonlinear and plastic flow characteristics of Belgium Boom clay.
|
|
Received: 16 April 2012
|
|
|
|
| [1] 姚仰平，侯 伟. 土的基本力学特性及其弹塑性描述[J]. 岩土力学，2009，30(10)：2 881–2 901.(YAO Yangping，HOU Wei. Basic mechanical behavior of soils and their elastoplastic modeling[J]. Rock and Soil Mechanics，2009，30(10)：2 881–2 901.(in Chinese))
[2] BORJA R I，LEE S R. Cam-clay plasticity，part I：implicit integration of elastoplastic constitutive relations[J]. Computer Methods in Applied Mechanics and Engineering，1990，78(1)：49–72.
[3] BORJA R I. Cam-clay plasticity，part II：implicit integration of constitutive equation based on a nonlinear elastic stress predictor[J]. Computer Methods in Applied Mechanics and Engineering，1991，88(2)：225–240.
[4] BORJA R I，TAMAGNINI C. Cam-clay plasticity，part III：extension of the infinitesimal model to include finite strains[J]. Computer Methods in Applied Mechanics and Engineering，1998，155(1/2)：73–95.
[5] BORJA R I. Cam-clay plasticity，part V：a mathematical framework for three-phase deformation and strain localization analyses of partially saturated porous media[J]. Computer Methods in Applied Mechanics and Engineering，2004，193(48/49/50/51)：5 301–5 338.
[6] 孙德安，姚仰平，殷宗泽. 初始应力各向异性土的弹塑性模型[J]. 岩土力学，2000，21(3)：222–226.(SUN De?an，YAO Yangping，YIN Zongze. An elastoplastic model for soil with initially stress- induced anisotropy[J]. Rock and Soil Mechanics，2000，21(3)：222–226.(in Chinese))
[7] LIU M D，CARTER J P. A structured Cam-clay model[J]. Canadian Geotechnical Journal，2002，39(6)：1 313–1 332.
[8] CARTER J P，BOOKER J R，WROTH C P. A critical state soil model for cyclic loading[C]// Soil Mechanics—Transient and Cylic Loading. [S.l.]：[s.n.]，1982：219–252.
[9] 范庆来，栾茂田，杨 庆. 修正剑桥模型的隐式积分算法在ABAQUS中的数值实施[J]. 岩土力学，2008，29(1)：269–273.(FAN Qinglai，LUAN Maotian，YANG Qing. Numerical implementation of implicit integration algorithm for modified Cam-clay model in ABAQUS[J]. Rock and Soil Mechanics，2008，29(1)：269–273.(in Chinese))
[10] 范庆来，栾茂田，倪宏革. 循环荷载作用下软基上大圆筒结构弹塑有效应力分析[J]. 水利学报，2008，39(7)：836–842.(FAN Qinglai，LUAN Maotian，NI Hongge. Elastoplastic effective stress analysis of soft soil foundation of large-diameter cylindrical structure subjected to cyclic loading[J]. Journal of Hydraulic Engineering，2008，39(7)：836–842.(in Chinese))
[11] KOHLER R，HOFSTETTER G. A cap model for partially saturated soils[J]. International Journal for Numerical and Analytical Methods in Geomechanics，2008，32(8)：981–1 004.
[12] 张 锋. 计算土力学[M]. 北京：人民交通出版社，2007：31. (ZHANG Feng. Computational soil mechanics[M]. Beijing：China Communications Press，2007：31.(in Chinese))
[13] SHENG D C，SLOAN S W. Load stepping schemes for critical state models[J]. International Journal for Numerical Methods in Engineering，2001，50：67–93.
[14] 康国政. 非弹性本构理论及其有限元实现[M]. 成都：西南交通大学出版社，2010：78–100.(KANG Guozheng. Inelastic constitutive theory and its finite element implementation[M]. Chengdu：Southwest Jiaotong University Press，2010：78–100.(in Chinese))
[15] HUANG J S，GRIFFITHS D V. Observations on return mapping algorithms for piecewise linear yield criteria[J]. International Journal of Geomechanics Mechanics，2008，8(4)：253–265.
[16] SIMO J C，TAYLOR R L. Consistent tangent operators for rate-independent elastoplasticity[J]. Computer Methods in Applied Mechanics and Engineering，1985，48(1)：101–118.
[17] SHENG D，SLOAN S W，YU H S. Aspects of finite element implementation of critical state models[J]. Computational Mechanics，2000，(6)：185–196.
[18] 于洪丹. Boom clay渗流–应力耦合长期力学特性研究[博士学位论文][D]. 武汉：中国科学院武汉岩土力学研究所，2010.(YU Hongdan. Study on long-term hydro-mechanical coupled behavior of Belgium Boom clay[Ph. D. Thesis][D]. Wuhan：Institute of Rock and Soil Mechanics，Chinese Academy of Sciences，2010.(in Chinese)) |
|
|
|
2012, Vol. 31 
