Kendiliğinden Yerleşen Betonla Yapılan Kolon-Kiriş Birleşimlerinde Donatı Oranı Etkisinin Değerlendirilmesi

Yüksek süneklik gerektiren kolon-kiriş düğüm noktaları gibi korunmasız bölgelerde, beklenmedik yüklemeler altında, sünek betona ihtiyaç duyulmaktadır. Alternatif olarak, kendiliğinden yerleşen beton (KYB), deprem etkisi altinda elemanların daha sünek davranış gösteren bir yapıya ulaşmak için son yıllarda büyük ilgi yaratan bir beton türüdür. Bu tipteki betonların belirgin özellikleri yüksek performans, segregasyona karşı yüksek direnç ve yerleşme için iç veya dış vibrasyona ihtiyaç duyulmamasıdır. Deprem bölgelerinde, süneklik, özellikle eğilmeye maruz kalan yapısal bağlantı noktalarının performansında önemli bir faktördür ve bu davranış plastik yerdeğiştirme kapasitesindeki artıştan kaynaklanmaktadır. Bu makalede, KYB kullanılan ve farklı donatı oranlarındaki dört adet kolon-kiriş düğüm noktasının yük-yerdeğiştirme davranışının deneysel ve teorik analizleri açıklanmaktadır. Bu araştırmanın teorik aşamasında, üç boyutlu sonlu elemanlar metodu (SEM), Seismostruct doğrusal olmayan yazılımı kullanılarak, deneysel-nümerik sonuçlar karşılaştırılmış ve yük-yerdeğiştirme diyagramları çizdirilmiştir. Deneysel sonuçlar ve doğrusal olmayan SEM modeli, kolon-kiriş düğüm noktalarında işlenebilir beton olarak KYB’un kullanımının, betonarme yapılarda süneklik ve enerji yutma kapasitesi bakımından tatmin edici bir performansa sahip olduğunu göstermiştir.

Anahtar Kelimeler:

Kolon- Kiriş düğüm noktası, SEM, Yük-yerdeğiştirme, Kendiliğinden yerleşen beton, İşlenebilir beton

EVALUATION OF REINFORCING BARS RATIO EFFECTS ON SCC BEAM-COLUMN JOINT PERFORMANCE

Beam-column joints require a high ductility during the unexpected loadings that necessitate the need for ductile concrete in such unprotected locations. Alternatively, self-compacting concrete (SCC) is a sort of concrete which has generated tremendous interest throughout the last decades in order to reach a ductile structural elements during the seismic actions. Specific properties of this type of concrete include high performance, high resistance against segregation and needless to internal or external vibration in order to compact. In the seismic regions, ductility is one of the most important factors in the design of reinforced concrete (RC) members, especially structural joints flexural performance; it is due to the enhance in the capability of plastic deformability. This paper describes load-displacement behavior of experimental and theoretical analysis of four SCC beam-column joints with different percentage of the ratio of the reinforcing bars (ρ). In the theoretical phase of this investigation three-dimensional nonlinear finite element method (FEM) model i.e., Seismostruct was used and the load-deflection diagrams were plotted to compare the test results with the numerical output. The experimental results and nonlinear FEM modeling indicate that using SCC as a workable concrete in beam-column joints of reinforced concrete structures has satisfactory performance in terms of ductility and energy dissipations.

Keywords:

Beam-column joint, Ductility, FEM, Load-deflection, Self-compacting concrete,

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