Effect of Selected Cross-section Geometry on the Seismic Performance of Concrete Gravity Dams

Öz

In this study, the effect of section geometry on the seismic performance of concrete gravity dams was investigated. For this purpose, six different cross-sectional geometries widely-used at the design phase of concrete gravity dams were selected and the numerical models were adapted to the Gunduzler, Naras and Andiraz dams. Thus, the effect of section geometry on the seismic demands have been examined without changing the variables used during the actual design. Equal amounts of material were used in all of the selected sections. So, it was investigated which section type allowed the most optimal use of the material. Acoustic fluid elements were utilized for simulating the interaction between the reservoir and the dam body. The numerical models were analyzed under the effect of three different earthquake scenarios. According to the analysis results, it was observed that Section K3 produced the most favorable results. 

Anahtar Kelimeler

• Section geometry,Seismic performance,Gravity dams

Beton Ağırlık Barajların Sismik Performanslarına Seçilen Kesit Geometrisinin Etkisi

Öz

Bu çalışmada, kesit geometrilerinin beton ağırlık barajların sismik performanslarına etkisi incelenmiştir. Bu amaçla, beton ağırlık barajların tasarımı aşamasında kullanılagelen altı farklı kesit geometrisi seçilmiş ve oluşturulan numerik modeller üç farklı yüksekliğe sahip Gündüzler, Naras ve Andıraz barajlarına uyarlanmıştır. Böylece tasarım aşamasında kullanılan değişkenleri değiştirmeksizin, kesit geometrilerinin barajların sismik taleplerine etkisi incelenmiştir. Seçilen kesitlerin tamamında eşit miktarda malzeme kullanılmıştır. Böylelikle hangi kesit tipinin malzemeyi en optimum şekilde kullanmaya izin verdiği araştırılmıştır. Numerik modellerde rezervuar etkileşimi için akustik akışkan elemanlar kullanılmıştır. Modeller üç adet deprem senaryosuna tabi tutulmuştur. Yapılan analiz sonuçlarına göre Kesit K3’ün en elverişli sonuçları ürettiği gözlemlenmiştir. 

Anahtar Kelimeler

• Kesit geometrisi,Sismik performans,Ağırlık barajlar

Kaynakça

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