Anisotropic shear strength behavior of a compacted soil and its application to slope stability analysis

本研究的目的是通过实验阐明压实土的各向异性抗剪强度特性，并开发考虑各向异性效应的路堤边坡稳定性分析的计算机程序。结果可总结如下：1。对从压实模型地基上以不同角度提取的试样进行了多次三轴压缩试验。然后根据库仑方程、破坏时的莫尔圆和各试件破坏面倾角，推导出各向异性抗剪强度方程。抗剪强度方程中的黏聚力和内摩擦角都是试样取向的函数。有趣的是，这些函数与McLamore等人提出的各向异性沉积岩的函数具有相同的形式。黏聚力和内摩擦角也表示为各试件剪切面与顺层面夹角的函数。基于这些函数进行的稳定性分析表明，抗剪强度各向异性比各向同性抗剪强度假设得到的安全系数值更小，临界滑移面形状更平坦。

The purpose of this study is to clarify experimentally the anisotropic shear strength characteristics of a compacted soil and to develop a computer program for the slope stability analysis of embankments consisting of the soil considering the anisotoropic effect. The results may be summarized as follows :1.A number of triaxial compression tests were conducted on the samples extracted at various angles from a compacted model ground. Then an anisotropic shear strength equation has been derived from the Coulomb equation, Mohr circles at failure and the inclination angle of the failure plane in each specimen.2.Cohesion and angle of internal friction appearing in the shear strength equation are both functions of sample orientations. It is interesting to note that the functions have the same form as those proposed by McLamore et al.for anisotropic sedimentary rocks.3.The cohesion and angle of internal friction are also expressed as functions of the angle between the shear plane and the bedding plane in each specimen. Stability analyzes performed based on these functions show that the shear strength anisotropy leads to smaller values of the factor of safety and flatter critical slip surfaces in shape than those obtained from the isotropic shear strength assumption.