Pei-Qing Zhao / Institute of Mechanics, Chinese Academy of Sciences
Wen-Gang Qi / Institute of Mechanics, Chinese Academy of Sciences
Local scour is a major cause of bridge collapses, leading to significant financial losses and safety risks. Despite progress in understanding local scour, empirical formulas remain dominant in bridge foundation design. These conventional approaches, however, are inherently constrained by their specific experimental origins, failing to fully elucidate the underlying scour mechanisms and demonstrating notable limitations in terms of applicable data ranges and scale effects. To address these challenges, this study develops a novel physics-based model for predicting the temporal evolution of local scour depth around pile foundations. By incorporating the concept of localized effective flow work, which quantifies the energy transfer from the obstructed flow to the sediment bed within the scour hole based on the phenomenological theory of turbulence, a prediction model for the time development of local scour depth around a pile is proposed. Validation against experimental data confirms that the proposed model effectively captures the temporal development of scour depth. This approach not only reduces reliance on empirical coefficients but also provides deeper physical insight into the scour process, offering enhanced predictive capability across varying hydraulic conditions.