A debris flow is one of the most dangerous types of geophysical mass flows moving downward mountain slopes and consist of a mixture of soil and rocks with a significant quantity of interstitial fluid. They can travel at extremely rapid velocities affecting long distances due to the significant influence of pore-water pressures on the propagation stage. In this paper, a novel two-phase depth-integrated SPH numerical model is applied to simulate a debris flow in which the effects of bed entrainment and pore-water pressure evolution, essential components to performed debris flows risk assessment, are included. The model was applied to simulate the dynamics of Yu Tung debris flow which is an appropriate benchmark case to examine the applicability of the developed model, as bed entrainment and pore-water pressure evolution were key aspects that affected the moving mass dynamics. The developed two-phase depth-integrated SPH-FD model is applied to assess the structural countermeasure of the bottom drainage screen, used to reduce the impact of debris flows. The reasonable results obtained from the analysis indicate that the model is capable to properly reproduce the propagation of the debris flow and more importantly to correctly perform the time-space evolution of pore water pressures during the whole deformation process from initiation through propagation, over an impermeable and permeable bottom boundary, up to deposition.

泥石流是向下移动到山坡上的最危险的地球物理质量流之一，它由土壤和岩石的混合物以及大量的间隙液组成。由于孔隙水压力对传播阶段的显着影响，它们可以以极快的速度传播，影响长距离。本文采用一种新颖的两相深度积分SPH数值模型来模拟泥石流，其中包括了床夹带和孔隙水压力演变的影响，这是进行泥石流风险评估的必要组成部分。该模型用于模拟鱼洞泥石流的动力学，这是检验开发模型适用性的适当基准案例，床夹带和孔隙水压力演变是影响运动质量动力学的关键方面。将已开发的两相深度综合SPH-FD模型用于评估底部排水筛的结构对策，以减少泥石流的影响。从分析中得出的合理结果表明，该模型能够正确再现泥石流的传播，更重要的是能够正确地执行整个变形过程（从始发到传播）在不渗透层上的孔隙水压力的时空演化。和可渗透的底部边界，直至沉积。用于减少泥石流的影响。从分析中得出的合理结果表明，该模型能够正确再现泥石流的传播，更重要的是能够正确地执行整个变形过程（从始发到传播）在不渗透层上的孔隙水压力的时空演化。和可渗透的底部边界，直至沉积。用于减少泥石流的影响。从分析中得出的合理结果表明，该模型能够正确再现泥石流的传播，更重要的是能够正确地执行整个变形过程（从始发到传播）在不渗透层上的孔隙水压力的时空演化。和可渗透的底部边界，直至沉积。