Inherent anisotropy is a crucial aspect to consider to improve one's understanding of the behavior of granular materials, in particular, noncoaxial responses under proportional and nonproportional loadings. This article investigates the capability of a strain space multiple mechanism model to reproduce complex responses of inherently anisotropic soils under various loading paths. The constitutive model has been expanded upon to account for the effect of inherent anisotropy by incorporating a new function along with three additional parameters; two of these parameters, $a_1$ and $a_2$, control the degree of anisotropy, whereas the third parameter, ${\theta }_0$, represents the principal direction of inherent anisotropy. Laboratory experimental data regarding the complex anisotropic responses of Toyoura sand under various loading paths are used to validate the constitutive model. The model is found to successfully simulate the anisotropic drained soil responses under monotonic proportional and nonproportional loadings as well as those under loading involving the rotation of the principal stress axis by considering the additional anisotropic parameters. Furthermore, the simulated responses of inherently isotropic materials are compared with those of anisotropic materials to numerically investigate the influence of inherent anisotropy (ie, the anisotropic parameters) on soil behavior under such loading conditions.

中文翻译：

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颗粒材料应变空间多机理模型中考虑载荷路径下固有各向异性的非同轴性

固有的各向异性是要考虑的一个重要方面，可以提高人们对颗粒材料性能的理解，特别是在比例和非比例载荷下的非同轴响应。本文研究了应变空间多机理模型在各种载荷路径下再现固有各向异性土的复杂响应的能力。本构模型已经扩展，通过合并一个新函数以及三个附加参数来考虑固有各向异性的影响。其中两个参数，${\mathrm{一个}}_{\mathrm{1个}}$ 和 ${\mathrm{一个}}_{\mathrm{2个}}$，控制各向异性的程度，而第三个参数， ${\theta }_0$代表固有各向异性的主要方向。关于丰山砂在各种载荷路径下的复杂各向异性响应的实验室实验数据被用来验证本构模型。通过考虑附加的各向异性参数，发现该模型可以成功模拟单调比例和非比例载荷以及涉及主应力轴旋转的载荷下的各向异性排水土的响应。此外，将固有各向同性材料的模拟响应与各向异性材料的模拟响应进行比较，以数值研究固有各向异性（即各向异性参数）在这种载荷条件下对土壤行为的影响。