BETONARME KESİTLERİN DOĞRUSAL ELASTİK ÖTESİ DAVRANIŞINDA TÜKETİLEN ENERJİYE BOYUNA DONATI ORANININ, ENİNE DONATI ARALIĞININ VE EKSENEL YÜKÜN ETKİSİ

Öz

Gerçek malzeme davranışları esas alınarak veya deneysel yoldan elde edilen eğilme momenti-eğrilik ilişkisi yardımıyla kesitlerin elastik ötesi davranışı ile ilgili birçok soruya cevap bulunabilmektedir. Kesit akma eğriliğinden en büyük eğrilik değerine kadar olan eğilme momenti-eğrilik grafiğinin alanı, elastik ötesi davranışta kesitte tüketilen enerjiyi ifade etmektedir. Tüketilen enerjideki artış kesit sünekliğindeki artışa da karşılık gelmektedir. Bu çalışma kapsamında, monotonik yükleme altındaki betonarme kesitlerin doğrusal olmayan davranışta tükettikleri enerji hesaplanmış ve kesit enerji tüketimlerine boyuna donatı oranının, enine donatı adım aralığının ve eksenel yükün etkisi araştırılmıştır. Seçilen betonarme kesitlerde pratikteki mühendislik uygulamalarında sıkça karşılaşılan farklı boyuna donatı oranları, farklı sargı donatısı aralıkları ve farklı eksenel yükler için eğilme momenti-eğrilik ve enerji analizleri gerçekleştirilmiştir. Enerji tüketimi açısından enine donatı adım aralığı ile kesit sünekliği arasında ters orantılı bir ilişki olduğu, eksenel yükteki artışın genel olarak sünekliği azalttığı ve betonarme elemandaki enerji tüketiminin eksenel yükteki artışla birlikte azaldığı sonucu elde edilmiştir.

Anahtar Kelimeler

• Boyuna donatı oranı, sargı donatısı aralığı, eksenel yük, enerji tüketimi, süneklik

EFFECTS OF LONGITUDINAL REINFORCEMENT RATIO, TRANSVERSE REINFORCEMENT SPACING AND AXIAL LOAD ON THE INELASTIC ENERGY CONSUMPTION OF REINFORCED CONCRETE SECTIONS

Öz

Many questions about nonlinear behavior of RC sections can be answered by the help of moment-curvature relations which can be obtained from experimental ways or theoretical approach by considering material stress- strain curves. Area of the moment-curvature relation of the section from yield curvature to ultimate curvature expresses the inelastic energy consumption of the section in its unit length. Increase in inelastic energy consumption of the section corresponds to the increase in ductility of the section with the same time. Within the scope of this study, the inelastic energy consumption of RC sections under monotonic loading is calculated and the effect of longitudinal reinforcement ratio, transverse reinforcement spacing and axial load of the section to the inelastic energy consumption is researched analytically. Moment-curvature and inelastic energy consumption analyses of the RC sections which are frequently used in engineering applications are performed for different longitudinal reinforcement ratios, different transverse reinforcement spacing’s and different axial loads. It is obtained from the study that there is inversely proportional relation between transverse reinforcement spacing and inelastic energy consumption of the section. Increase in axial load of the section decreases the section ductility and energy consumption of the section and this result can be seen from the inelastic energyconsumption versus curvature graphs by obtaining the inelastic energy consumption values that correspond to different axial load levels.

Anahtar Kelimeler

• Longitudinal reinforcement ratio, transverse reinforcement spacing, axial load, energy consumption, ductility

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