New Empirical Model for Breaching of Earth-Rock Dams

Empirical models are widely used in dam risk analysis because they can estimate the dam breach parameters easily, which enables a quantitative analysis of the breach process to be conducted. In this study, by applying a regression-based method to a database collected worldwide, a new empirical model has been developed that can predict the peak discharge, final breach average width, and failure time. The reservoir shape coefficient, the ratio of the water level when the dam is breached and the final breach depth, as well as the dam height, have been selected as the control variables of the model. Further, in the new model, the dam types (i.e., homogeneous dam, zoned-fill dam and core wall dam), as well as the failure modes (i.e., overtopping and piping) are considered. The advantage of this new model is that the formulas have been developed based on a larger database of dam breach cases and the choice of the input parameters. The model performance and comparison with the existing empirical models testify to the rationality of the new model.