Risk evaluation of dam-break environmental impacts based on the set pair analysis and cloud model

Many dams have been constructed around the world. Compared with the potential losses of life and economy, the environmental impacts caused by dam breach were less analyzed. As a systematic theory, the set pair analysis method deals with both the certainty and uncertainty of a system or process as a whole. But when dealing with the analysis of environmental impacts with obvious uncertainty, the fuzziness feature of the indices was not considered comprehensively. Hence, this paper introduced the connection degree of set pair analysis in five grades, and the cloud model-based weight calculation method to improve the evaluation. The proposed method was applied to the case study of Qianping Reservoir, Henan Province, China, showing that the comprehensive environmental impacts caused by the potential dam breach were medium. The results of the study indicate that the proposed method is applicative and provides reliability for environmental impacts evaluation of dam breach.