The cross-anisotropic nature of soil strength has been studied and documented for decades, including the increased propensity for cross-anisotropy in layered materials. However, current engineering practice for tailings storage facilities (TSFs) does not appear to generally include cross-anisotropy considerations in the development of shear strengths. This is despite the very commonly seen layering profile in subaerially deposited tailings. To provide additional data to highlight the strength cross-anisotropy of tailings, high-quality block samples from three TSFs were obtained and trimmed to enable hollow cylinder torsional shear tests to be sheared at principal stress angles of 0 and 45° during undrained shearing. The consolidation procedures were carried out such that the drained rotation of principal stress angle that would precede potential undrained shear events for below-slope tailings was reasonably simulated. The results indicated the significant effects of cross-anisotropy on the undrained strength, instability stress ratio, contractive tendency and brittleness of each of the three tailings types. The magnitude of cross-anisotropy effects seen was generally consistent with previous published data on sands.

中文翻译：

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评估三种尾矿类型的不排水强度交叉各向异性

几十年来，已经研究和记录了土壤强度的交叉各向异性性质，包括层状材料中交叉各向异性倾向的增加。然而，目前尾矿储存设施 (TSF) 的工程实践似乎一般不包括在抗剪强度发展中的交叉各向异性考虑。尽管在地下沉积的尾矿中非常常见的分层剖面是这样的。为了提供额外的数据来突出尾矿的强度交叉各向异性，从三个 TSF 中获取高质量块样品并进行修整，以使空心圆柱体扭转剪切试验能够在不排水剪切过程中以 0 和 45° 的主应力角进行剪切。执行固结程序，以便合理模拟坡下尾矿潜在不排水剪切事件之前的主应力角的排水旋转。结果表明，交叉各向异性对三种尾矿的不排水强度、失稳应力比、收缩趋势和脆性均有显着影响。所看到的交叉各向异性效应的大小与之前公布的沙子数据基本一致。