EXPERIMENTAL INVESTIGATION OF WIND LOADS ON 45° PITCHED GABLE AND HIP ROOFS

Yıl 2015, Cilt: 56 Sayı: 665, 53 - 61, 01.05.2015

Yücel Özmen Ertan Baydar

Öz

In this study, flow fields around a low-rise building model with 45º pitched gable and hip roofs have been investigated experimentally in order to search the wind loads that can damage the building roofs. The experiments were carried out in an atmospheric boundary layer that is modeled in the wind tunnel. Atmospheric boundary layer was simulated with combination of barrier, elliptic vortex generators and elements of roughness and a 150 mm height boundary layer was formed at 15 m/s wind velocity. The mean and fluctuating surface pressures were measured on the building models having gable and hip roofs immersed in boundary layer in detail for various wind directions to observe critical suction zones on the roof surfaces. It is found that suction effect on the hip roof is lower than suction effect on the gable roof.

Anahtar Kelimeler

Atmospheric boundary layer, gable roof

45° EĞİME SAHİP BEŞİK VE KIRMA ÇATILAR ÜZERİNDEKİ RÜZGÂR YÜKLERİNİN DENEYSEL İNCELENMESİ

Öz

Bu çalışmada, bina çatılarını hasara uğratabilen rüzgâr yüklerinin araştırılması amacıyla, 45° eğime sahip beşik ve kırma çatılı bina modelleri yüzeylerindeki basınç dağılımları deneysel olarak incelenmiştir. Deneyler rüzgâr tünelinde modellenen atmosferik sınır tabaka akışında gerçekleştirilmiştir. Akışın modellenmesinde bariyer, eliptik girdap üreticiler ve pürüzlülük elemanları kombinasyonu kullanılmış ve 15 m/s’lik serbest akış hızında, 150 mm yüksekliğinde bir sınır tabaka oluşturulmuştur. Yüzey basınçlarının ortalama ve çalkantı değerlerinin ölçümü, sınır tabaka içerisine yerleştirilmiş, beşik ve kırma çatılı iki bina modeli üzerinde farklı rüzgâr geliş açılarına göre ayrıntılı bir şekilde gerçekleştirilerek emme etkilerinin kritik olduğu bölgeler belirlenmiştir. Kırma çatı üzerindeki emme etkisinin, beşik çatıya göre daha düşük olduğu bulunmuştur.

Anahtar Kelimeler

Atmosferik sınır tabaka, beşik çatı

Kaynakça

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