ANALYSIS OF STRESS-STRAIN BEHAVIOR OF CLAY ALONG TYPICAL STRESS PATHS IN PRACTICAL PROJECTS
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摘要: 分别采用Mohr-Coulomb模型、修正剑桥模型和UH模型预测正常固结土在常规三轴压缩、三轴伸长和平均主应力p减小的压缩工况中典型路径下土的变形特性。Mohr-Coulomb模型为理想弹-塑性模型,屈服之前为弹性变形,屈服之后为变形无限增大的弹-塑性变形。修正剑桥模型能够较好地模拟压缩路径条件下正常固结土的应力-应变关系,但模型较高地估计了伸长路径条件下土的强度。UH模型为适用于正常固结土和超固结土的弹-塑性模型,其建模简单,参数与剑桥模型相同。对于正常固结土,UH模型能够退回到剑桥模型。通过采用基于SMP强度准则的变换应力方法,模型能够合理描述土的三维应力状态的特性。Abstract: The Mohr-Coulomb model, the modified Cam-clay model UH model were used to model the stress-strain relationships under the triaxial compression, extension and compression with decreasing principal stress conditions.The result predicted by the Mohr-Coulomb model, as a perfect elasto-plastic model, was elastic stress-strain relationship when stress point was in yield surface and is elasto-plastic stress-strain relationship with the constant stress and infinite increasing deformation when stress point was on yield surface under the triaxial compression condition. The modified Cam-clay model could be used to predict the behavior of the normally consolidated clay in the triaxial test well, but it over-estimated the strength of clay under the extension condition. The UH model for the normally consolidated clay and over-consolidated clay had the same parameters as those in the modified Cam-clay model. For the normally consolidated clay, the UH model was the same as the modified Cam-clay model. By applying the transformed stress method based on SMP criterion, the UH model could describe the property of clay in threedimension stress space.
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Key words:
- stress path /
- stress-strain relationship /
- elasto-plastic /
- constitutive model
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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):2881-2902. [2] 姚仰平,侯伟,罗汀.土的统一硬化模型[J].岩石力学与工程学报,2009,28(10):2135-2151. [3] 陈惠发,萨里普A F.土木工程材料的本构方程[M].武昌:华中科技大学出版社,2001. [4] 谢定义,姚仰平,党发宁.高等土力学[M].北京: 高等教育出版社,2008. [5] 罗汀,姚仰平,侯伟.土的本构关系[M].北京: 人民交通出版社,2010. [6] 郑颖人,沈珠江,龚晓南.岩土塑性力学原理: 广义塑性力学[M].北京: 中国建筑工业出版社,2002. [7] Roscoe K H, Burland J B.On the Generalised Stress-Strain Behaviour of an Ideal Wet Clay[C]∥ Heyman J,Leckie F A.Engineering Plasticity.Cambridge: Cambridge University Press,1968,535-609. [8] Yao Y P,Hou W,Zhou A N.UH Model: Three-Dimensional Unified Hardening Model for Overconsolidated Clays [J].Geotechnique,2009,59(5):451-469. [9] 姚仰平,侯伟,周安楠.基于Hvorslev 面的超固结土模型[J].中国科学: E 辑,2007,37(11):1417-1429. [10] 侯伟,姚仰平.统一硬化模型在复杂加载条件下的应用[J].北京航空航天大学学报,2008,34(9):1105-1108. [11] Matsuoka H,Yao Y P,Sun D A.The Cam-Clay Models Revised by the SMP Criterion[J].Soils and Foundations, 1999, 39(1):81-95. [12] Yao Y P,Zhou A N,Lu D C.Extended Transformed Stress Space for Geomaterials and Its Application[J].Journal of Engineering Mechanics,2007,133(10):1115-1123. [13] 侯伟,姚仰平.剑桥模型与统一硬化模型超固结土特性描述的对比分析[J].工业建筑,2011,41(9):18-23. [14] Nakai T,Hinokio M.A Simple Elastoplastic Model for Normally and Over-Consolidated Soils with Unified Material Parameters[J].Soils and Foundations,2 004,44 ( 2):53-70.
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