Bülent AKBAŞ, Bora AKŞAR, Ercan Şerif KAYA, Ferit ÇAKIR

Merkezi çaprazlı çerçevelerde dayanım farklılığı sonucu oluşan burulma etkileri

Bu çalışma, çapraz elemanların dayanımındaki rastlantısal farklardan dolayı merkezi çaprazlı çerçeveler(MÇÇ) kullanılarak tasarlanmış yapıların kuvvetli deprem yer hareketleri altında sergilediği burulmadavranışını incelemeyi amaçlamıştır. Bu çalışmada, çaprazlardaki dayanım farklılığının, çaprazın gerçekdayanımının minimum akma gerilmesinden (Fy) değil, arttırılmış (beklenen) akma gerilmesinden (RyFy) kaynaklandığı kabulü yapılmıştır. Bu amaçla alçak ve orta katlı yapıları temsilen, üç ve dokuz katlı dışçerçeveleri MÇÇ olarak tasarlanmış farklı çapraz dayanım konfigürasyonlarına sahip iki yapıdaki burulmanedeniyle oluşabilecek doğrusal olmayan davranış kuvvetli deprem yer hareketleri altında incelenmiştir.Yapının kapasite eğrisi farklı durumlar için elde edilmiştir ve zaman tamın alanında doğrusal olmayan analizyöntemi ile belirlenen göreli kat ötelemesi oranları sunulmuştur

Relative story displacements and torsional effects caused by strength variations in concentrically braced frames

This study will investigate the accidental torsional response in steel structures designed by CBFs due to thevariation in strength of braces under strong earthquake ground motions. For this study, it is assumed that thevariation in strength of braces would come from the expected yield stress (RyFy) rather than minimum specified yield stress (Fy) of brace member. For this purpose, inelastic torsional response of a three and ninestory building having perimeter CBFs having various brace strength configurations subjected to strongearthquake ground motions is investigated in detail. The results are presented in the form of base shear vs.roof displacement (pushover curve, capacity curve) and drift ratio through nonlinear dynamic responseanalyses

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