Unlike water inrush occurring in karst and faults, debris flow inrush involves a greater number of debris such as mud and sand, and exhibit a more complex evolution process of disaster, characterized by significant progressive erosion phenomenon. At present, the progressive erosion characteristics from fine particles to coarse particles before the burst of debris flow inrush is still unclear, and there is a lack of model to predict the volume of debris flow inrush. In this study, the debris flow inrush accidents of Anshi tunnel crossing the contact zone are introduced. Then, using a coupled computational fluid dynamics and discrete element method (CFD-DEM), the debris flow inrush is simulated in multi-scales: from sample-scale to engineering-scale. The erosion characteristics and friction angle degradation during progressive erosion in sample-scale, and the formation mechanism of debris flow inrush in engineering-scale are studied. Finally, based on the results of multi-scale simulations, a model to predict the volume of debris flow inrush considering progressive erosion is established. The reliability of the model is verified by comparison with volume of debris flow inrush of Anshi tunnel. The results of this study contribute to understanding the formation mechanism of debris flow inrush and predicting its volume.

中文翻译：

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泥石流突流的渐进侵蚀特征及形成机理分析及其数值模拟及其应用


与岩溶和断层中的突水不同，泥石流突水涉及更多的泥沙等碎屑，并表现出更复杂的灾害演化过程，具有显著的渐进侵蚀现象。目前，泥石流突流爆发前由细颗粒到粗颗粒的渐进侵蚀特征尚不清楚，缺乏预测泥石流突流体积的模型。本文介绍了安石隧道穿越接触区的泥石流突涌事故。然后，使用耦合计算流体动力学和离散元方法 （CFD-DEM），在从样本尺度到工程尺度等多尺度上模拟泥石流突流。研究了样品尺度上渐进式侵蚀过程中的侵蚀特性和摩擦角退化，以及工程尺度下泥石流突陷的形成机制。最后，基于多尺度仿真结果，建立了考虑渐进侵蚀的泥石流突流体积预测模型。通过与安石隧道泥石流突流体积的对比，验证了模型的可靠性。本研究结果有助于理解泥石流突潮的形成机制并预测其体积。