Farklı Sarılı Beton Modelleri için Betonarme Kolonların Doğrusal Olmayan Davranışlarının İncelenmesi

Öz

Betonarme kare kolonların farklı sargılı beton modellerine göre gerilme-şekil değiştirme ve moment-eğrilik davranışı analitik olarak incelenmiştir. Enine donatı oranı ve beton sınıfının betonarme kolon modellerinin davranışına etkisi incelenmiştir. Farklı sargılı beton modelleri için sargı etkinlik katsayısı, etkili yanal basınç gerilmesi, sargılı beton basınç dayanımı, maksimum beton gerilmesinde birim kısalma ve sargılı betondaki maksimum basınç birim şekil değiştirme değerleri hesaplanmıştır. İkinci bölümde, farklı tasarım parametrelerinin moment-eğrilik ilişkileri üzerindeki etkilerinin incelenmesi için parametrik bir araştırma yapılmıştır. TBDY (2018), Mander modeli (1988), Saatcioğlu ve Ravzi (1992) sargılı beton modelleri kullanılarak betonarme kesitlerde analitik moment-eğrilik ilişkileri elde edilmiştir. Parametrelerin betonarme kare kolon davranışı üzerindeki etkileri, enine kesitin eğrilik ve moment kapasitesi açısından değerlendirilmiştir. Betonarme kolon modellerinde, gerilme-şekil değiştirme ve moment-eğrilik ilişkileri elde edilmiş ve farklı parametrelere göre karşılaştırılmıştır. Mander modelinden elde edilen sargılı beton basınç dayanımı ve nihai moment değerleri, enine donatı minimum aralık değerlerine yakın olduğunda Saatçioğlu ve Ravzi modeline göre daha yüksektir. Mander modelinden ve TBDY (2018) ile elde edilen sonuçlar birbirine yakındır.

Anahtar Kelimeler

• Gerilme-şekil değiştirme
• moment-eğrilik
• doğrusal olmayan davranış
• sargılı beton dayanımı
• yanal sargı basıncı

Investigation of Nonlinear Behavior of the Reinforced Concrete Columns for Different Confined Concrete Models

Öz

Stress-strain and moment-curvature behavior of the reinforced concrete (RC) square columns have been analytically investigated according to different confined concrete models. The effect of transverse reinforcement diameter, transverse reinforcement spacing and concrete grade on the behavior of RC column models were investigated. For different confined concrete models, the confinement effectiveness coefficient, effective lateral confining stress, confined concrete compressive strength, strain at maximum concrete stress and ultimate concrete compressive strain values were calculated. In the second part, a parametric investigation was carried out for examining the effects of different design parameters on the moment-curvature relationships. Analytical moment-curvature relationships were obtained for RC cross-sections by using the TBEC (2018), Mander model (1988), Saatcioglu and Ravzi (1992) confined concrete models. The effects of the design parameters on the RC square column behavior were evaluated in terms of moment capacity and the curvature of the cross-section. In RC column models, stress-strain and moment-curvature relationships are obtained and compared according to different parameters. Confined concrete strength and the ultimate moment values obtained from the Mander model were higher than the Saatcioglu and Ravzi model when the transverse reinforcement close to the minimum spacing values. The results obtained from the Mander model and TBEC (2018) are close to each other.

Anahtar Kelimeler

• Stress-strain
• moment-curvature
• nonlinear behavior
• confined concrete strength
• lateral confining stress

Kaynakça

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