Abstract

Storage basins, check dams, barriers and other control works are often used to reduce threats and damage from flow-like mass movements. This paper deals with the effectiveness of two storage basins of the Italian Alps against debris flows followed by a flash flood induced by short heavy rainfall in 2009. Referring to detailed field data, the propagation of flows and their interaction with the control works are analysed by using an advanced numerical depth-averaged flow propagation model based on SPH (Smooth Particle Hydrodynamics) technique. The Froude dynamic similitude is here used to provide a quantitative descriptor of the dynamic features of the flows. The numerical results show that debris flows accumulated in the storage basins since they propagated downslope like subcritical flows. On the contrary, flash floods overpassed the control works having moved along the entire path as supercritical flows. Those findings are fully supported by some previous studies and provide a further contribution to the relevant topic of granular flow-obstacle interaction.

摘要

蓄水池、止水坝、障碍物和其他控制工程通常用于减少类似流动的质量运动的威胁和破坏。本文讨论了意大利阿尔卑斯山的两个蓄水池对泥石流以及 2009 年短时间强降雨引发的山洪暴发的有效性。参考详细的现场数据，分析了流的传播及其与控制工程的相互作用使用基于 SPH（光滑粒子流体动力学）技术的先进数值深度平均流动传播模型。Froude 动态相似度在这里用于提供流动动态特征的定量描述。数值结果表明，泥石流像亚临界流一样沿斜坡向下传播，因此在储存盆地中积累。相反，山洪以超临界水流的形式沿着整条路径移动，越过了控制工程。这些发现得到了一些先前研究的完全支持，并为颗粒流-障碍物相互作用的相关主题提供了进一步的贡献。