During the application of semi-theoretical models to predict peak discharges for breached embankment dams, it is often encountered to be lack of necessary model parameters such as breach height. In order to solve this deficiency and improve the application of the semi-theoretical models for estimating the peak discharge, a mathematical relation is proposed to predict the breach height (H_b) using the water depth above breach bottom (H_w) based on a subset of a composite database (72 historical dam failures). The breach height relation has a high coefficient of determination (R²) when it is applied in the composite database. Using the prediction by the breach height relation as a substitute for the observation, these semi-theoretical models used here produce similar results in terms of both prediction accuracy and uncertainty. Moreover, the dispersion of the flood peak discharge predicted by forecasting models is weakened and the skewness is improved by adopting the breach height relation. Therefore, the application of semi-theoretical models to predict peak discharges can be improved obviously. So, it is found that the breach height using the proposed relation can be a satisfactory substitute when the observed value of H_b is unavailable in a dam failure. Besides, the prediction accuracy will decrease slightly with the increase of database, but the decrease is limited. It should be noted that the proposed breach height relation is only suitable for predicting the height of embankment dam breach in principle.

中文翻译：

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半理论模型的增强，用于预测堤坝溃坝的最大流量

在应用半理论模型来预测堤坝溃坝的峰值流量时，经常会遇到缺少必要的模型参数（例如堤坝高度）的情况。为了解决该缺陷并提高半理论模型在估算峰值流量中的应用，提出了一种数学关系式，该方法利用基于突破口底部的水深（H _w）来预测突破口高度（H _b）。复合数据库的子集（72个历史大坝故障）。缺口高度关系具有较高的确定系数（R ²）在组合数据库中应用时。使用突破高度关系的预测结果代替观察值，此处使用的这些半理论模型在预测准确性和不确定性方面均产生相似的结果。此外，通过采用突破高度关系，可以减小预测模型预测的洪峰流量的离散度，并改善偏斜度。因此，可以大大改善半理论模型在预测峰值流量方面的应用。因此，发现当H _b的观测值时，使用建议的关系的破坏高度可以令人满意地替代。在大坝故障中不可用。此外，随着数据库的增加，预测精度将略有下降，但下降幅度是有限的。应该注意的是，建议的违背高度关系原则上仅适合于预测堤坝违规高度。