Three different models of considering trash rack-dam interaction are introduced for analyzing dynamic characteristics and dynamic response of a concrete gravity dam in this paper.Elastic connection and rigid connection between trash rack and dam

as well as uncoupled interaction of the trash rack and dam have been considered.The results show the models for simulating trash rack-dam interaction all have a great effect on seismic safety analysis of the concrete gravity dam.The crack depth of the dam and the displacement of the dam crest increase obviously with the trash rack-dam interaction.The predicted result according to China Code is biased unsafe for the dam.However

the result considering elastic connection between trash rack and dam is biased safe for the dam.