The Effect of Eaves Types to Wind Pressures on 45° Pitched Gable Roofs

Year 2016, Volume: 21 Issue: 1, 45 - 62, 25.03.2016

Yücel Özmen Ertan Baydar

Abstract

In this study, flow field around a low-rise building model with 45º pitched gable roof having different eave types has 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 roofs having different eave types in detail for various wind directions to observe critical suction zones on the roof surfaces. It is seen that eaves increase suction loads on the roof corners. Usage of a special eave causes more critical peak pressures on the roof corners compared with normal eave and without eave cases. 

Keywords

Atmospheric boundary layer; Gable roof; Normal eave; Special eave; Pressure coefficient; Suction loads

FARKLI SAÇAK TİPLERİNE SAHİP 45° EĞİMLİ BEŞİK ÇATILI BİNA MODELLERİ ÜZERİNDE RÜZGAR BASINÇLARI

Abstract

Bu çalışmada, bina çatılarını hasara uğratabilen rüzgar yüklerinin araştırılması amacıyla, farklı saçak tiplerine sahip 45° eğimli beşik çatılı bina modelleri yüzeylerindeki basınç dağılımları deneysel olarak incelenmiştir. Deneyler rüzgar 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, saçaksız, normal saçaklı ve yelkıran saçaklı bina modelleri üzerinde farklı rüzgar geliş açılarına göre göre ayrıntılı bir şekilde gerçekleştirilerek emme etkilerinin kritik olduğu bölgeler belirlenmiştir. Saçakların çatı köşesindeki emme yükünü arttırdığı; yelkıran saçağın normal saçağa göre %30, saçaksız duruma göre %70 daha kritik pik basınçlar oluşturduğu görülmüştür.

Keywords

Atmosferik sınır tabaka, Beşik çatı, Normal saçak, Yelkıran saçak, Basınç katsayısı, Emme yükü

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