In this study, a series of shear wave velocity tests were conducted on two types of sand-gravel mixtures with a wide range of particle size distributions. The effect of the particle shape on the small-strain shear modulus (G_max) was investigated using a customized, large-scale triaxial apparatus. The results showed that G_max increases with the decrease in particle roundness when the uniformity coefficient (C_u) is less than a certain value. However, this increasing trend gradually flattens with the further increase of C_u. Thus, the effect of particle shape on the G_max varies with the particle gradation. The performances of six relationships proposed in the literature for predicting G_max were compared and evaluated in terms of their predictive capabilities. An empirical G_max model based on the Hardin and Black equation was proposed by including a Fourier-based shape factor modified by C_u. The model can characterize the difference in the variation of G_max with C_u due to different particle shapes and was thereafter validated. Furthermore, the model serves as a reference guide for estimating the G_max of soils with various particle size distributions through their particle characteristics.

在这项研究中，对两种粒径分布范围较广的沙砾混合物进行了一系列剪切波速度测试。使用定制的大型三轴设备研究了颗粒形状对小应变剪切模量（G _max）的影响。结果表明，当均匀度系数（C _u）小于一定值时，G _max随着颗粒圆度的降低而增加。但是，随着C _u的进一步增加，这种增加的趋势逐渐趋于平坦。因此，颗粒形状对G _max的影响随粒子等级变化。比较了文献中提出的用于预测G _max的六个关系的性能，并根据其预测能力进行了评估。提出了一个基于Hardin和Black方程的经验G _max模型，其中包括C _u修正的基于傅立叶的形状因子。该模型可以表征由于颗粒形状不同而导致的G _max随C _u变化的差异，并随后进行了验证。此外，该模型还可以作为估算G _max的参考指南 通过其颗粒特性分布各种粒径的土壤。