The clogging–unclogging process in gap-graded soils is a result of the migration of seepage-driven fines, which subsequently induces measurable changes in the local hydraulic gradients. This process can be temporally observed in the variations of Darcy's hydraulic conductivity (K). The current study proposes an integrated statistical Monte Carlo approach combining the discrete-element method and two-dimensional computational fluid dynamics simulations to estimate the flow-dependent constriction-size distribution (CSD) for a gap-graded soil. The computational inferences were supported with experimental results using an internally stable soil, which was subjected to one-dimensional flow stimulating desired hydraulic loadings: a hydraulic gradient lower than the critical gradient applied as a multi-staged loading pattern. The 35th percentile size of the flow-dependent CSD (D_c35) for both internally stable and unstable gap-graded soils becomes approximately equal to D_c35 at steady state. However, a greater variation of larger constrictions persists for the unstable soils. This pilot study has shown the applicability of the proposed method to estimate flow-dependent CSD for a wide range of experimentally observed K values.

中文翻译：

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间隙分级土壤中与流量相关的收缩尺寸分布：统计推断

间隙级配土壤中的堵塞-疏通过程是渗流驱动细粒迁移的结果，随后会引起局部水力梯度的可测量变化。这个过程可以在达西水力传导率（K）。目前的研究提出了一种综合统计蒙特卡罗方法，结合离散元方法和二维计算流体动力学模拟来估计间隙分级土壤的流动相关收缩尺寸分布 (CSD)。计算推论得到了使用内部稳定土壤的实验结果的支持，该土壤经受一维流动刺激所需的水力载荷：低于临界梯度的水力梯度作为多级加载模式应用。对于内部稳定和不稳定的间隙级配土壤，与流量相关的 CSD ( D _{c 35} ) 的第 35 个百分位大小大约等于D _{c 35}处于稳定状态。然而，对于不稳定的土壤，较大收缩的较大变化仍然存在。这项试点研究表明，所提出的方法可适用于估计各种实验观察到的K值的流量相关 CSD。