Fuzzy evaluation on seismic behavior of reservoir dams during the 2008 Wenchuan earthquake, China

The post-earthquake rapid risk evaluation on the reservoir dams plays an important role in the emergency danger disposal and reinforcement. The fuzzy Data Envelopment Analysis/Assurance Region (DEA/AR) approach was introduced evaluating the seismic behavior of reservoir dams, in which the seismic risk of dam site, the structure characteristics of reservoir dam, and pre-earthquake state of dams were taken as input variables; in the meantime the seismic crack, leakage and deformation of dams induced by the earthquake were taken as output variables. The proposed DEA/AR approach was adopted to evaluate the seismic behavior of 19 reservoir dams suffered from Wenchuan earthquake in Luojiang County, Sichuan Province. The input and output variable values all originated from the post-earthquake field investigation data. And the weight values of DEA/AR model were determined by the entropy weight method which was able to avoid the interference from subjective consciousness. The evaluation results on the seismic behavior obtained from DEA/AR approach were mainly consistent with those from the experts in the field, which verified that the approach was valid and rational. The proposed DEA/AR approach was based on the objective data and the cognitive ability of the model self to give the evaluation results, which was adaptive for the situation that the seismic behaviors of the reservoir dams were not easy to distinguish. A ranking method was recommended to judge the order of quality of seismic behavior of the evaluated reservoir dams. The ranking results could serve for the post-earthquake emergency disposal and reinforcement.