Abstract The cyclic behavior of silty sands is complex in that it depends not only on packing density and confining pressure but also on fines content. How to properly model the behavior is emerging as an active area of research in geomechanics and engineering. This paper presents an attempt to formulate a critical state-based constitutive model for describing the cyclic loading behavior of sand with varying fines content. Based on several important experimental findings from recent studies, a unified characterization of the state-dependent elastic modulus and plastic hardening modulus is proposed such that only one set of elastic and hardening parameters is required for sand with varying fines content. By comparing with systematic experimental data, it is shown that the model can produce reasonably good predictions for undrained cyclic responses of silty sands under a range of void ratios, effective confining stresses and fines contents. In particular, the model successfully predicts the experimentally observed variations of sand behavior with fines content under cyclic loading.

中文翻译：

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粉质砂岩循环行为的统一临界状态本构模型

摘要 粉砂岩的循环行为是复杂的，它不仅取决于填充密度和围压，还取决于细粒含量。如何正确地模拟行为正在成为地质力学和工程研究的一个活跃领域。本文试图制定一个基于临界状态的本构模型，用于描述具有不同细粒含量的沙子的循环加载行为。基于最近研究的几个重要实验结果，提出了状态相关弹性模量和塑性硬化模量的统一表征，这样对于具有不同细粒含量的砂，只需要一组弹性和硬化参数。通过与系统的实验数据对比，结果表明，该模型可以在一定范围的孔隙比、有效围压和细粒含量下对粉砂质砂的不排水循环响应产生相当好的预测。特别是，该模型成功地预测了实验观察到的沙子行为随循环载荷下细粒含量的变化。