Coupled Model of Variable Fuzzy Sets and the Analytic Hierarchy Process and its Application to the Social and Environmental Impact Evaluation of Dam Breaks

Dam construction is important for economic development. However, the safety risks posed by dangerous dams are unacceptable. The need for the consequence evaluation of dam breaks has been increasing to reduce all types of losses caused by dam breaks in downstream areas. However, research on this topic is relatively scarce, particularly in the field of social and environmental impact assessments. This study combined the analytic hierarchy process, variable fuzzy set, and an index system to overcome the limitations of traditional evaluation methods and the problem in which the obtained evaluation level cannot be located accurately. An integrated variable fuzzy evaluation model was proposed to evaluate the social and environmental impact of dam breaks. To explore and compare the presented method with other traditional methods, a case study of the Changlong Reservoir was conducted. The comparison results showed that the proposed method features accurate algorithms and a scientific evaluation process. It can convey the severity of social and environmental impact to a certain degree by using the eigenvector of level H, which can improve the accuracy of assessment results. Meanwhile, various factors in the object to be evaluated were comprehensively considered. Therefore, the proposed method can be applied to the social and environmental impact evaluation of dam breaks.