Backward erosion piping (BEP) is a leading internal erosion mechanism for flood protection system failures. A model capable of predicting critical hydraulic conditions for BEP initiation at multiple scales while also incorporating soil variability is a pressing need. This study formulates and validates a novel multiscale probabilistic BEP initiation framework with incorporation of soil variability. The framework is based on a grain‐scale probabilistic model and the weakest link theory, and the theory of rate processes. The multiscale framework proposed herein is validated through a wide range of available experimental data from independent sources, encompassing tests performed at multiple scales. Following calibration with small‐scale experimental data, the model demonstrates accurate prediction of critical hydraulic gradients at larger scales (3–6 orders of magnitude difference), including the ability to capture the grain size dependence of BEP initiation and providing uncertainty estimates. A systematic analysis is performed to uncover the effects of different soil properties on multiscale critical hydraulic conditions.

中文翻译：

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后向侵蚀管道启动的多尺度随机建模，从颗粒动力学到 Weibull 统计。第二部分：模型验证和应用


后向侵蚀管道 （BEP） 是防洪系统故障的主要内部侵蚀机制。一个能够在多个尺度上预测 BEP 启动的关键水力条件，同时还能结合土壤变化的模型是一项紧迫的需求。本研究制定并验证了一种新的多尺度概率 BEP 启动框架，并结合了土壤变异性。该框架基于颗粒尺度的概率模型和最弱环节理论，以及速率过程理论。本文提出的多尺度框架通过来自独立来源的广泛可用实验数据进行了验证，包括在多个尺度上进行的测试。在使用小规模实验数据进行校准后，该模型证明了在较大尺度（3-6 个数量级差异）下准确预测临界水力梯度，包括捕获 BEP 起始的晶粒尺寸依赖性并提供不确定性估计的能力。进行了系统分析，以揭示不同土壤特性对多尺度临界水力条件的影响。