Abstract:  Reservoir induced seismicity has been the important environmental problem affecting a dam safety, which can generate some extent damage to a dam. In this paper, taking the Xinfengjiang Reservoir induced seismicity and Koyna Reservoir induced seismicity for examples, we discussed the impacts of reservoir induced seismicity on the concrete dams. It can be seen that, for this kind of dams, the dam crest is the prone to damage position, additionally, the roads and the non-structural constructions on the crest increase the possibility of damage. Therefore, when one does the seismic design, the dynamic interaction and the effects of the higher order vibration modes on the stress of the dam crest should be taken into consideration. On the basis of observed seismic acceleration records, the seismic dynamic response analysis was done. It shows that the dam heel and toe are the areas of high tensile stress, and it is critical in the stress analysis of concrete dams, and that the stiffness mutation position and the breakthroughs of slope on the upstream face and downstream face are the weak regions of earthquake-resistant building. In summary, considering the various impacts of reservoir induced seismicity on dams, a good earthquake fortification is the key factor ensuring the dam safety.

Key words: reservoir induced seismicity , concrete dam , dynamic response analysis , earthquake fortification