Micromechanics analysis for unsaturated granular soils

被引：0
作者：
Zhang W. [1 ]
Zhao C. [1 ]
机构：
[1] School of Civil Engineering, Beijing Jiaotong University
来源：
Acta Mechanica Solida Sinica | 2011年 / 24卷 / 3期
关键词：
anisotropy; average stress; capillary stress; fabric; pendular state; unsaturated granular soils;
D O I：
10.1016/S0894-9166(11)60028-1
中图分类号：
学科分类号：
摘要：
This paper aims at establishing an anisotropic stress expression for unsaturated pendular-state granular soils. Using the second-order fabric tensor, we formulate a micromechanics scheme of soils with statistically averaging method, and reveal that the macroscopic average stress of unsaturated granular soils in pendular-state is not isotropic. Not only is the stress from contact forces anisotropic due to the fabric, but also the capillary stress is directional dependent, which is different from the common point that the capillary stress is isotropic. The capillary stress of unsaturated pendular-state granular soils is determined by the orientation distribution of contact normals, so it is closely related to the initial and induced anisotropy of soils. Finally, DEM numerical simulations of triaxial compression tests of pendular-state soils at different degrees of saturation are used to verify the existence of above anisotropy of stresses. © 2011 The Chinese Society of Theoretical and Applied Mechanics.
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页码：273 / 281
页数：8
相关论文
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