Slit dam is an open-check barrier structure widely used in mountainous regions to resist the destructive impacts of granular flows. To examine the dynamics of granular flow impact on slit dams, a numerical study by discrete element method (DEM) is presented in this article. The study considers dry granular materials flowing down a flume channel and interacts with slit dams installed at the lower section of the flume. The particle shape is explicitly considered by particle clumps of various aspect ratios. The slit dams are modeled as rigid and smooth rectangular prisms uniformly spaced at in the flume. Four key stages of granular flow impact on the slit dams have been identified, namely, the frontal impact, run up, pile up, and static deposition stages. In the impact process, the kinetic energy of the granular flow is dissipated primarily by interparticle friction and damping. The trapping efficiency of the slit dams decreases exponentially with the relative post spacing, while it increases with the particle clump aspect ratio. The numerical results can provide new insights into the optimization of relative post spacing for slit dam design.

中文翻译：

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干粒流对狭缝坝影响的离散元分析

裂隙坝是一种广泛应用于山区的开放式止回屏障结构，以抵御颗粒流的破坏性影响。为了检查颗粒流对狭缝坝的动力学影响，本文提出了离散元法 (DEM) 的数值研究。该研究考虑了沿着水槽通道流动的干燥颗粒材料，并与安装在水槽下部的狭缝坝相互作用。颗粒形状由各种纵横比的颗粒团块明确考虑。狭缝坝被建模为在水槽中均匀分布的刚性和光滑的矩形棱柱。已经确定了颗粒流对狭缝坝的四个关键阶段，即正面撞击阶段、上升阶段、堆积阶段和静态沉积阶段。在冲击过程中，颗粒流的动能主要通过颗粒间摩擦和阻尼耗散。狭缝坝的捕集效率随着相对柱间距呈指数下降，而随着颗粒丛纵横比的增加而增加。数值结果可以为狭缝坝设计的相对柱间距的优化提供新的见解。