Çelik-Beton Kompozit Kat Döşemesi Yangın Dayanım Deneyi

Bu çalışmada, Türkiye’de araştırma odaklı ilk çelik-beton kompozit kat döşemesi yapısal yangın deneyi gerçekleştirilmiştir. Bu çalışma, Türkiye’de gerek yangın yönetmelikleri açısından gerekse yapısal yangın konusunda teorik, nümerik ve deneysel araştırmalardaki eksiklikleri gidermeyi amaçlamaktadır. Yüksek katlı çelik bir yapı için tasarlanmış kompozit döşemenin iki kenarında simetrik bir birleşim mekanizması kullanılmıştır. Yangın fırınına monte edildikten sonra döşemenin alt yüzeyi ISO834 standart yangın eğrisiyle 105 dakika ısıtılmış ve sonrasında 90 dakika kontrollü olarak soğutulmuştur. Deney sırasında yapının sehim ve sıcaklık ölçümleri yapılmıştır. Alınan sonuçlar, beton döşemenin membran davranışı göstererek yük taşıyıcı özelliğini yangın boyunca devam ettirdiğini göstermektedir. Dolayısıyla kompozit kat döşemelerinde ikincil çelik kirişlerin yalıtımsız kalması önerilmektedir.

Anahtar Kelimeler:

Yangın dayanımı testi, simetrik birleşim mekanizması, yapısal yangın mühendisliği, kompozit döşeme, çelik bağlantı

Fire Resistance Test of a Steel-Concrete Floor System

This study conducts the first research based structural fire resistance test of a steel-concrete composite floor in Turkey. The goal of this research is to fill the knowledge gaps in the current Turkish building code for the structural fire safety and provide valuable insight for the development of new theoretical, computational and experimental research. The tested composite floor is specifically designed for a high-rise steel building. The floor is equipped with a patent pending mechanism to provide symmetric boundary conditions on two edges. The floor is subjected to ISO-834 standard fire curve from the bottom surface for 105 minutes followed by 90 minutes cooling. Displacement and temperature measurements show that at elevated temperatures, the concrete slab carries the load by the tensile membrane action without a contribution of the secondary beam. This study suggests that secondary steel beams do not need to be fire protected as the concrete slab is adequate to carry the gravity loading.

Keywords:

Fire resistance test, symmetric connection mechanism, structural fire engineering, composite floor, steel connection,

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