较全面地总结了国内外大坝老化与病害评价研究成果，在此基础上，提出了以病害指数衡量大坝病害程度，给出了病害指数的计算方法，并根据病害指数值，将大坝病害程度及病险状况划分为相应的 5 个等级。建立了基于病害指数的大坝溃决可能性评价模型，提出了以溃决指数衡量水库大坝溃决可能性，并根据溃决指数值，将水库大坝溃决可能性划分为相应的 5 个等级。应用大坝溃决可能性评价模型评价了沙河集水库大坝溃决可能性，评价结果表明，根据溃决指数判定大坝溃决可能性具有较好的适用性。大坝溃决可能性评价模型可为病险水库大坝溃决可能性评价提供参考；建议推广应用该评价模型，并深化研究大坝病害演变规律及其与大坝溃决可能性的关联关系。

The research results of dam aging and disease assesssment at home and abroad are comprehensively reviewed.On these bases, the dam disease index is put forward to judge the disease degree of dam, and the calculation method of the index is provided. According to the disease index, the dam disease degrees and dangerous conditions are respectively divided into five corresponding grades. The assessment model of possibility for dam breach based on dam disease index is developed, the dam breach index in the model is used to judge the possibility of dam breach and the possibility of dam breach is divided into five corresponding grades according to the index. The assessment model has been applied to evaluate the possibility of dam breach in Shaheji reservoir. And the evaluation result shows that the dam breach index is applicable for judging the possibility of dam breach. The model could be a reference for the possibility assessment of dam breach of dangerous reservoir. We suggest that the model should be gradually popularized, and the evolution law of dam disease as well as its correlation with the possibility of dam breach should be further studied.