This study experimentally investigates the influences of grain shape and gradation on stress-dilatancy parameters. For this purpose, consolidated-drained triaxial tests are conducted on five different granular materials. Specimens are sheared following two different stress paths; axial compression and lateral extension, in order to monitor the influence of stress path on the investigated problem. For each soil, grain shapes, sizes and stress-dilatancy parameters are experimentally determined. Moreover, available data in literature for other sands are compiled with the data of this study. This allows the investigation of the dependence of stress-dilatancy parameters on gradation and grain shape characteristics. Especially with this study, variations of stress-dilatancy constants with grain characteristics are examined. Statistically significant relationships are obtained for predicting stress-dilatancy parameters as functions of average grain shapes. On the other hand, influences of stress path and gradation on stress-dilatancy response are experimentally considered. Finally, compiled and determined data used in the development of the relationships are provided in the form of tables.

Graphic abstract

中文翻译：

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晶粒形状对应力-剪胀参数的影响

本研究通过实验研究了晶粒形状和梯度对应力-剪胀性参数的影响。为此，对五种不同的颗粒材料进行了固结排水的三轴试验。沿着两个不同的应力路径剪切试样。轴向压缩和横向延伸，以监视应力路径对所研究问题的影响。对于每种土壤，通过实验确定颗粒的形状，大小和应力-剪胀参数。此外，文献中可用于其他砂岩的可用数据也与本研究的数据进行了汇编。这允许研究应力-剪胀性参数对梯度和晶粒形状特征的依赖性。尤其是在这项研究中，研究了应力-剪胀常数随晶粒特性的变化。获得统计上显着的关系，以预测应力-剪胀参数作为平均晶粒形状的函数。另一方面，实验上考虑了应力路径和梯度对应力-剪胀响应的影响。最后，以表格的形式提供了在关系开发中使用的已编译和确定的数据。

图形摘要