Köprü ayağı oyulma derinliği ile düşey hız bileşeni arasındaki ilişkinin araştırılması

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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