The runup height and impact load of landslide debris are the key parameters for design of debris hazard mitigation structures. However, the movement of obstacle (e.g., deformation of flexible barrier) still cannot be quantitatively considered in the existing analytical models. This study proposes general equations for landslide-debris impact under vertical jet and momentum jump modes. Especially, the influence of flow regime and obstacle movement (in the form of a modified Froude number), state of granular material, compressibility (density change), and flow resistance within the jump volume are explicitly considered in the momentum jump model. Through comparison between model prediction and experimental results, it is found that the vertical jet model prediction agrees well with the physical measurements. While the discrepancy between the momentum jump model and experimental results mainly comes from the inappropriate characterization of the unsteady flow properties (velocity and flow depth). Systematic parametric study demonstrates that the functionality of debris-flow flexible barrier primarily relies on the deflection of barrier, and the state of granular material also affects the impact load of dry granular flows.

滑坡碎屑的爬升高度和冲击载荷是设计减轻碎屑灾害的结构的关键参数。但是，障碍物的移动（例如（柔性屏障的变形）仍然无法在现有的分析模型中进行定量考虑。这项研究提出了在垂直射流和动量跳跃模式下滑坡-泥石撞击的一般方程。尤其是，在动量跳跃模型中明确考虑了流动状态和障碍物运动（以改进的弗洛德数形式），粒状材料的状态，可压缩性（密度变化）和跳跃体积内的流动阻力的影响。通过模型预测与实验结果的比较，发现垂直射流模型预测与物理测量结果吻合良好。动量跳跃模型与实验结果之间的差异主要来自不稳定流动特性（速度和流动深度）的不恰当表征。