Köprü ayağı oyulma derinliği ile düşey hız bileşeni arasındaki ilişkinin araştırılması

Yıl 2016, Cilt: 22 Sayı: 6, 427 - 432, 20.12.2016

Oğuz Kağan Çetin Can Saçan Gökçen Bombar

Öz

Köprü
ayakları etrafında oluşan yerel oyulmalar önemli bir mühendislik problemi
olarak kabul edilmektedir. Bu çalışmada, 6 cm ve 9 cm çapa sahip iki köprü
ayağı, içinde 0.43 mm medyan dane çapında sediment bulunan 18 m uzuluğunda ve
70 cm genişliğinde dikdörtgen kesitli bir kanal içine yerleştirilmiş ve bu
ayaklar etrafında oluşan oyulmalar ölçülmüştür. Her biri 4 saat sürdürülen 5
adet deney gerçekleştirilmiştir. Deneyler sırasında, oyulma derinliğinin
zamanla değişimi (



















) ve
ayağın 6 cm membasında tabandan 4 cm yukarıdaki noktasal hız değişimi zamana
bağlı olarak kaydedilmiştir. Düşey hız bileşeni (

) ile
oyulma derinliği arasındaki ilişki araştırılmış ve bu parametrelerin boyutsuz
biçimleri için bir denklem önerilmiştir. Sözkonusu bağıntının, literatürde
bulunan sınırlı miktardaki çalışmaya ait veri ile uyum içinde olduğu
görülmektedir.

Anahtar Kelimeler

Köprü ayağı, Oyulma derinliği, Düşey hız, Zamanla değişim

Kaynakça

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