The failure of landslide dams is a sudden geological disaster, and thus their formation and failure greatly threaten the security of people's lives and property. In this research, the influences of different flume gradients, dam heights, and downstream slope angles relative to the flume bed on the overtopping breaching process of noncohesive landslide dams are explored through 12 sets of model experiments. Based on these experimental results, the dam overtopping breaching can be divided into four stages: initiation, head cutting, acceleration, and riverbed rebalancing. The variation in the erosion rate (E_AX and E_BX) and the downstream slope angle relative to the horizontal line (Φ) exhibit clear differences in the different stages. The influences of the flume gradient, dam height, and downstream slope angle on the breaching process of landslide dams are different. In our experiments, accumulation bodies could only form in the middle and lower parts of the downstream dam face when the total height from the spillway to the flume bed was greater than 15 cm. In addition, the downstream slope angle relative to the horizontal line determined the breaching process and stage of the dam overtopping breaching. Since the dam breach evolution mode and dam overtopping breaching process were mainly affected by the dam height and downstream slope angle relative to the horizontal line, the evolution of the longitudinal section in the process of dam body failure can be divided into four modes based on our experimental results. The applicability of the widely used empirical equations for the erosion rate was assessed using the experimental data, which revealed obvious differences between the measured and calculated erosion rates. However, the erosion rate and the shear stress at the soil/water interface exhibited a good correlation in every test. Therefore, these widely used empirical equations need to be improved in future research. This preliminary research provides a basis for subsequent studies of dam breaching using models and a scientific reference for the prevention and mitigation of landslide dams.

滑坡大坝的破坏是突发的地质灾害，因此其形成和破坏极大地威胁着人们的生命财产安全。在这项研究中，通过12组模型实验，探讨了不同的水槽坡度，坝高和相对于水床床的下游倾斜角对非粘性滑坡坝顶破破坏过程的影响。根据这些实验结果，大坝顶破破坏可分为四个阶段：启动，截水，加速和河床再平衡。侵蚀率（E _AX和E _BX）和下游倾斜角相对于水平线（Φ）的变化）在不同阶段表现出明显的差异。水槽坡度，坝高和下游坡度角对滑坡溃坝过程的影响是不同的。在我们的实验中，当从溢洪道到水槽的总高度大于15 cm时，只能在下游坝面的中下部形成堆积体。另外，相对于水平线的下游倾斜角决定了溃坝的过程和大坝突破的阶段。由于大坝破坏演化模式和大坝突破破坏过程主要受大坝高度和相对于水平线的下游倾斜角的影响，根据我们的研究，大坝本体破坏过程中纵向截面的演化可分为四种模式。实验结果。使用实验数据评估了广泛使用的经验公式对侵蚀速率的适用性，结果表明，测得的侵蚀速率与计算得出的侵蚀速率之间存在明显差异。但是，在每个试验中，土壤/水界面的侵蚀速率和剪切应力都显示出良好的相关性。因此，这些广泛使用的经验方程式有待在未来的研究中加以改进。这项初步研究为使用模型的后续大坝破坏研究提供了基础，并为预防和缓解滑坡大坝提供了科学参考。在每个测试中，土壤/水界面的侵蚀速率和剪切应力都表现出良好的相关性。因此，这些广泛使用的经验方程式有待在未来的研究中加以改进。这项初步研究为使用模型的后续大坝破坏研究提供了基础，并为预防和缓解滑坡大坝提供了科学参考。在每个测试中，土壤/水界面的侵蚀速率和剪切应力都表现出良好的相关性。因此，这些广泛使用的经验方程式有待在未来的研究中加以改进。这项初步研究为使用模型的后续大坝破坏研究提供了基础，并为预防和缓解滑坡大坝提供了科学参考。