Experimental Study on Pressure Characteristics of Gravity Dam Surface under Impact of Landslide-Generated Impulse Waves

Landslide-generated impulse waves of a mountain-river reservoir will endanger the dam body's stability and the dam structure's safety and even pose a significant threat to the property safety of downstream residents. Timely prediction of dam surface pressure is essential for dam safety assessment. The pressure distribution characteristics and variation law of the gravity dam surface under the impact of landslide-generated impulse waves are studied through a three-dimensional physical model test. The results show that the landslide volume and angle are the key control factors of the first wave amplitude in front of the dam. The maximum and minimum pressures are near the water surface and at two-thirds of the water depth, respectively. The maximum pressure has a power function relationship with the maximum amplitude of the wave in front of the dam. Furthermore, the maximum amplitude of the first wave in front of the dam significantly influences the total pressure of the single-width wave on the dam surface. Based on the research results, the single-width wave total pressure prediction method is constructed under different first wave amplitudes in front of the dam, which can provide theoretical guidance and technical support for dam safety assessment and landslide-generated surge risk assessment.