Istanbul’da eski bir Mısır dikilitaşının koruma amaçlı yapısal değerlendirilmesi

Yıl 2020, , 169 - 182, 19.08.2020

Gulten Polat , Özden Saygılı

https://doi.org/10.17824/yerbilimleri.630560

Öz

Theodosius Dikilitaşı İstanbul'daki eski Hipodrom'da bulunan en önemli anıtlardan biridir. Dikilitaş, heykel tabanıyla bugün 24.77 metre yüksekliğindedir, ancak tarihi kayıtlar orijinal yapının belirgin şekilde daha yüksek olduğunu göstermektedir. Ayrıca, kayıtlar bazı parçaların nakliye nedeniyle Mısır'da geride kaldığını göstermektedir. Dikilitaş, özellikle depremler olmak üzere birçok doğal yıkıcı olaya maruz kalmıştır. Bilindiği gibi, Dikilitaş'ın bulunduğu bölge sismik olarak çok aktiftir çünkü Türkiye’de potansiyel olarak en yıkıcı fay sistemine sahip olan Kuzey Anadolu Fayı ve onun segmentleri bu bölgede gelişmiştir. Dikilitaş'ın korunması için sismik performansını değerlendirmek önemlidir. Bu amaçla, bu çalışmada,yapısal dinamik özellikler ve Dikilitaş'ın tepkisi incelenmiştir. Bu amaca ulaşmak için sonlu elemanlar yaklaşımı kullanılarak sayısal bir model oluşturulmuştur. Buna ek olarak, bu çalışmada gerçek yer hareketi verileri analiz edilmiştir. Çalışmanın en önemli bulgusu, Dikilitaş'ın uzun süre yıkıcı depremler yaşamasına rağmen, ortaya çıkan deformasyonun belirgin olmadığıdır. Depremlere karşı dayanıklılığı büyük olasılıkla inşa malzemeleriyle ilgilidir. 

Anahtar Kelimeler

Theodosius Dikilitaşı, sayısal analiz, dinamik analiz, deprem davranışı

Structural evaluation for the preservation of an ancient Egyptian Obelisk in Istanbul, Turkey

Öz

The "Obelisk of Theodosius" is one of the most important monuments located in the former Hippodrome in Istanbul, Turkey. The Obelisk with its sculpted base is 24.77 meters in height today, but historical recordings indicate that it was evidently higher originally. Additionally, the recordings show that some of the parts were left behind in Egypt due to transportation. The Obelisk has been exposed to many natural devastating events, particularly strong earthquakes. The monument is in a seismically very active region, Istanbul, located near one of the most devastating 
active faults of Turkey, the North Anatolian Fault. For the preservation of this obelisk, it is important to evaluate its seismic performance. For this purpose, in this study, the structural dynamic characteristics and the response of the obelisk were investigated. To achieve this aim, a numerical model was created using a finite element approach. In addition to this, real ground motion data were analyzed in this study. The most important finding of the study is that although the obelisk had experienced devastating earthquakes for a long time, revealed deformation is not 
noticeable. Its strength against earthquakes is most likely related to its constructed materials.

Anahtar Kelimeler

Obelisk of Theodosius, numerical analysis, dynamic analysis, earthquake behavior

Kaynakça

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