Abstract: Flood overtopping is a prominent type of tailings dam accidents,and a profound comprehension of the erosion and damage mechanisms and processes of tailings dam overtopping holds significant importance in advancing disaster prevention and reduction in tailings dams. To investigate the failure mechanism of tailings dam overtopping and proficiently forecast the occurrence of flood overtopping accidents,numerous scholars have conducted extensive research in recent years,resulting in an array of impressive research outcomes that offer scientific guidance for the prevention and control of tailings dam flood overtopping disasters. The research accomplishments on overtopping failure of tailings dams both domestically and internationally have been summarized and analyzed thoroughly,with particular attention given to the overtopping erosion failure of tailings dams through model experiments,mathematical models,numerical simulations,and other perspectives. The research findings have revealed the spatiotemporal laws of the development of tailings dam breach under the action of overtopping water flow and the evolution of tailings flow discharge,uncovering the mechanism of overtopping erosion failure of tailings dams. However,some limitations exist:① Regarding physical model tests,dam failure process,and impact analysis,single-factor tests are currently the primary means,failing to fully consider the coupling effects of multiple factors such as dam accumulation mode, boundary conditions,and material mechanical properties,leading to significant discrepancies between the test results and the actual situation. ② In terms of mathematical model analysis,the theories and formulas of earth-rock dams are still being referenced,resulting in notable differences between tailings dams and earth-rock dams in terms of structural shape,dam material, stacking technology,and storage capacity,as well as various differences in the properties of debris flows formed. Consequently, the conclusions drawn have significant errors compared to the actual tailings dam overtopping failure. Then,the current mathematical models of tailings pond overtopping failure prediction all consider the flood overtopping failure prediction of unreinforced tailings dams,and the reinforcement belt will play an important role in the development of flood overtopping failure of tailings dams. ③ The current mathematical models for predicting overflow and collapse of tailings dams primarily focus on the prediction of flood overflow and failure of unreinforced tailings dams,with reinforcement strips having a considerable impact on the development of flood overflow and collapse of tailings dams. In terms of numerical simulation calculations,the accuracy deviation of terrain measurement data and the lack of validation of corresponding large-scale model experiments pose challenges to ensuring the credibility of its calculation conclusions. To address these issues,several future research directions are proposed: ① Adopting multi-scale experimental models by combining large-scale model experiments with small-scale experiments for exploration and mutual verification. ② Developing more precise new soil collection instruments to obtain soil erosion coefficients and enhance existing soil erosion rate models. ③ Based on model experiments on the erosion process of tailings dam overtopping under the coupling effect of multiple factors,more comprehensive mathematical models should be developed for numerical simulation calculation.

Key words: tailings dam,overtopping,erosion mechanism,process of ulcer expansion,study progress,prospect