关键词: 抗震安全性能, 高拱坝, 坝体损伤体积, 评价指标, 地震

Abstract: With the continuous increase of arch dam height and fortification intensity, the traditional strength evaluation index can not meet the needs of seismic safety evaluation. In this paper, a finite element model is established to do the seismic safety assessment of 300 m high arch dams. The model takes the contact nonlinearity of transversal joints into account, the nonlinearity of concrete material of the dam body and nonliner effects of rock foundation fault. The variation of opening of the transversal joints, deformation of arch crest and damage ratio of dam body with seismic strength are analyzed by incremental dynamic analysis method. The results show that there are no marked change for the variation of the displacement of arch crest and the opening degree of horizontal joint with the seismic intensity though the upper part of the dam is damaged severely under strong earthquake. The displacement of arch crest and transversal joint opening are not suitable to be evaluation index and monitoring index of seismic safety of dam body. In contrast, the variation of the damage volume fraction of the dam body with the increase of seismic intensity appears to change abruptly, which reflects the overall damage state of the dam body and can be used as an evaluation index of the seismic safety of the arch dam. It is necessary to explore the relationship between the dam body deformation, transversal opening etc. and the damage of dam body and dam foundation in the future.

Key words: anti-seismic safety, high arch dam, damage volume ratio of dam body, evaluation index, earth quarke