Abstract Soil particle size distribution (PSD) is critical for assessing the potential for internal instability of sand–gravel soils, mainly because particle migration in sand–gravel soils owing to seepage forces affects almost all soil hydraulic properties during internal erosion processes. Therefore, a reliable PSD analysis is essential for revealing the mechanism of particle migration and internal instability of sand–gravel soils. At present, however, PSD is commonly calculated by manual interpretation methods and cannot be continuously and nondestructively analyzed during internal erosion processes. Those methods are lacking, however, in that it results in a failure to continuously determine the internal erosion condition. In this paper, a new approach with the ability to continuously predict the PSD changes in sand–gravel mixtures is introduced based on one-dimensional laboratory suffusion tests in a non-destructive nuclear magnetic resonance (NMR) system over a range of suffusion times. The results show that pore expansion and particle migration are an interactive process that controls suffusion development in sand–gravel mixtures. The proposed method is verified through experimental data measured by sieve analysis, and has potential to retrieve PSD information at different suffusion times.

中文翻译：

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使用孔径分布和孔隙率通过核磁共振估算粒度分布

摘要 土壤粒度分布（PSD）对于评估砂砾土内部不稳定性的可能性至关重要，主要是因为渗流作用导致砂砾土中的颗粒迁移影响了内部侵蚀过程中几乎所有的土壤水力特性。因此，可靠的 PSD 分析对于揭示砂砾土的颗粒迁移和内部不稳定性机制至关重要。然而，目前PSD通常通过人工解释方法计算，无法在内部侵蚀过程中进行连续和无损分析。然而，这些方法是缺乏的，因为它导致无法连续确定内部侵蚀条件。在本文中，基于非破坏性核磁共振 (NMR) 系统中的一维实验室扩散测试，在一定范围的扩散时间内引入了一种能够连续预测砂砾混合物中 PSD 变化的新方法。结果表明，孔隙膨胀和颗粒迁移是一个相互作用的过程，控制着砂砾混合物中的扩散发展。通过筛分分析测量的实验数据验证了所提出的方法，并且具有在不同扩散时间检索PSD信息的潜力。结果表明，孔隙膨胀和颗粒迁移是一个相互作用的过程，控制着砂砾混合物中的扩散发展。通过筛分分析测量的实验数据验证了所提出的方法，并且具有在不同扩散时间检索PSD信息的潜力。结果表明，孔隙膨胀和颗粒迁移是一个相互作用的过程，控制着砂砾混合物中的扩散发展。通过筛分分析测量的实验数据验证了所提出的方法，并且具有在不同扩散时间检索PSD信息的潜力。