Yakın-fay yer hareketi etkisindeki kablo-destekli köprülerin asinkronize dinamik analizi

Bu çalışmada, merkez açıklık uzunlukları birbirine yakın olan bir eğik kablo askılı ve bir asma köprü sistemi dikkate alınarak asinkronize yer hareketi durumunda söz konusu köprülerin yakın fay ve uzak fay yer hareketleri etkisindeki davranışları belirlenmeye çalışılmıştır. Japonya’da inşa edilen Tatara Köprüsü eğik kablo askılı köprü modeli olarak seçilirken, Türkiye’de inşa edilen Fatih Sultan Mehmet Köprüsü asma köprü modeli olarak tercih edilmiştir. Dikkate alınan köprü sistemlerinin üç boyutlu zaman tanım alanında analizi, Chi-Chi depreminin yakın fay ve uzak fay yer hareketi bileşenleri için gerçekleştirilmiştir. Çalışmadan elde edilen sonuçlar, dalga yayılma etkisinin köprü davranışları üzerinde karmaşık bir etkisinin olduğunu ve dalga yayılma hızına ve dikkate alınan yapısal tepkilere bağlı olarak sismik tepkileri arttırıp azaltabildiğini göstermektedir. Diğer taraftan merkez açıklıkları 1000 m civarında olan ve dolayısıyla diğer yapı sistemlerine göre daha yüksek titreşim periyotlarına sahip kablo destekli köprülerin, yakın fay yer hareketlerine maruz kaldığında daha büyük sismik talepler gösterebileceği anlaşılmaktadır.

Anahtar Kelimeler:

Eğik-kablo askılı köprü, asma köprü, yakın-fay yer hareketi, uzak-fay yer hareketi, asinkronize yer hareketi modeli

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