The seismic damage investigation data of 257 buildings in Qingchuan County during Wenchuan earthquake are statistically analyzed. The results indicate that the seismic damages of buildings with seismic design are obviously lower than those of buildings without seismic design, and the damages of the brick-wood structures are most severe, that of the bottom frame structures and masonry structures are second while that of the reinforced concrete frame structures are relatively slight.

JiYin hydraulic project is located at the branch of Keliya River, Yutian county of Xinjiang. During the stage of its planning and design, a magnitude 7.3 earthquake occurred 43km away from the southeast of the dam. As the earthquake was in the southeastern part of Altyn Tagh Fault which was recognized in the past as a low seismicity segment, the cognition about seismic surroundings had changed totally. Based on comparison between the two seismic safety evaluations on JiYin before and after the earthquake, epistemic uncertainties in probabilistic seismic hazard assessments have a significant effect on final results. Therefore, in order to mitigate earthquake disasters of dams, combination of probabilistic and deterministic methods should be applied for evaluating seismic hazards when large dams are constructed in strong seismicity regions.