Pressure Characteristics of Landslide-Generated Waves on Bridge Piers

In a reservoir area, landslides can generate waves that pose a significant threat to bridge piers, endangering both property and human safety. This study utilized three-dimensional water tank experiments to simulate the generation of landslide-induced waves and their impact on bridge piers located on both riverbanks. The analysis focused on the types and distribution patterns of wave pressures on bridge piers. The results reveal the following key findings: (1) The results show that the wave pressures on the piers can be classified into two types: Pulsating pressure (Ppu) and Resonance pressure (Pre). Ppu represents the pressure generated during the wave action process. Ppu closely corresponds to the wave height-time process, with frequencies ranging from 0.2 to 0.5 Hz. Pre occurs prior to Ppu. Pre represents high-frequency vibrational waves generated when bridge piers resonate during wave action. Pre is observed primarily in deep water conditions and on the opposite riverbank, with frequencies ranging from 300 to 900 Hz. (2) On the bridge piers of the opposite riverbank, Ppu exhibits a nearly vertical distribution along the water depth, while on the same side, Ppu exhibits a sawtooth-like decrease along the water depth. Ppu increases with greater landslide volume and steeper landslide angles, and the maximum wave pressure distribution occurs near the water surface. (3) The distribution of Pre/Ppu along the water depth exhibits three forms: multiple-peak, single-peak, and no-peak, with the maximum positions for all conditions of Pre/Ppu occurring at approximately one-third of the water depth from the surface (Y/h=0.3). Finally, predictive formulas for the maximum wave pressures are provided.