Karbon Fiber Takviyeli Elyaf Kumaşlarla Güçlendirilen Betonarme Kolonların Eş Merkezli ve Tek Doğrultulu Eğilme Yüklemeleri Altındaki Davranışının Deneysel Olarak İncelenmesi

Abstract

Betonarme kolonlar, yapının yaşlanması, çevresel etkiler, deprem vb. gibi durumlardan dolayı güçlendirilmesi ya da onarılması gereken en önemli yapısal elemanlardır. Bir yapı elemanı güçlendirilirken hangi etkilere maruz kaldıklarını tespit etmek oldukça önem arz etmektedir. Betonarme kolonlar da çoğu kez eş merkezli yüklemelere maruz kalsalar da özellikle kenar kolonlar dış merkezli olarak da yüklemelere maruz kalarak eğilme momentleri tesiri altında eksenel yük taşımaya çalışmaktadır. Bu çalışma kapsamında eş merkezli ve dış merkezli olarak yüklenen betonarme kolonların karbon fiber takviyeli elyaf kumaş (KFTEK) şeritler ile güçlendirilmesinin deneysel olarak incelenmesi amaçlanmıştır. Bu amaçla 6 adet büyük ölçekli deney elemanı üretilmiştir. Bu deney elemanlarından 2 adeti referans olarak seçilmiştir. Geriye kalan 4 adet deney elemanı is KFTEK şeritler ile güçlendirilmiştir. Yükleme tipi (eş ve dış merkezli) ve ankraj kullanımı değişkenler olarak belirlenmiştir. Şerit genişliği ve aralığı ise sabit tutulmuştur. Gerçekleştirilen deneysel çalışma sonucunda deney elemanlarının maksimum yük taşıma kapasitesi, başlangıç rijitliği, sünekliği ve enerji tüketim kapasitesi hesaplanarak sonuçlar karşılaştırılmıştır.

Keywords

• Betonarme Kolon
• Güçlendirme
• CFRP
• Eş merkezli yükleme
• Dış Merkezli yükleme.
• Betonarme Kolon, Güçlendirme, CFRP, Eş merkezli yükleme, Dış Merkezli yükleme.

Experimental Investigation of Behavior of Reinforced Concrete Columns Strengthening with Carbon Fiber Reinforced Polymer Under Axial and Uniaxial Bending Loadings

Abstract

Reinforced concrete columns are the most important structural elements that need to be strengthened or repaired due to situations such as aging of the structure, environmental effects, earthquake, etc. It is very important to determine what effects a structural element is exposed to while being strengthened. Although reinforced concrete columns are often subjected to concentric loads, especially side columns are also subjected to eccentric loads and try to carry axial loads under the influence of bending moments. In this study, it is aimed to experimentally investigate concentric and eccentrically loaded reinforced concrete columns strengthening with carbon fiber reinforced polymer (CFRP) strips. For this purpose, 6 large-scale test elements were fabricated. Two of these test elements were chosen as reference. The remaining 4 test elements are strengthened with CFRP strips. Loading type (concentric and eccentric) and anchor usage were determined as variables. The strip width and spacing were kept constant. As a result of the experimental study, the maximum load carrying capacity, initial stiffness, ductility and energy dissipation capacity of the test elements were calculated and the results were compared.

Keywords

• Reinforced Concrete Column
• Strengthening
• CFRP
• Concentric loading
• Eccentric loading

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