Betonarme Köprü Kolonlarında Plastik Mafsal Bölgelerinin Modellenmesi

Çok eksenli dinamik yükler etkisindeki betonarme köprü yapılarında, yüklemenin farklı aşamalarında elastik olmayan şekil değiştirmelerin dağılımının incelenmesi önemli ve zor bir problemdir. Betonarme bir köprü kolonunun doğrusal olmayan 3 boyutlu detaylı bilgisayar modeli ABAQUS sonlu elemanlar programında geliştirilmiş ve deprem sarsma tablalarında iki eksenli dinamik yükler altında köprü kolonunda ölçülen deformasyon değerleri model ile karşılaştırılmıştır. Yapılan deneysel çalışmalarda, betonarme köprü sistemine şiddeti giderek artan bir seri deprem yüklemesi uygulanmıştır. Sonlu elemanlar modelinde kolonlardaki plastikleşme bölgesinin yayılmasındaki değişiklikleri incelemek için tüm deprem şiddetleri için analizler yapılmıştır. Değerlendirme sonucu, kolonlarda oluşan plastikleşme bölgelerinin uzunluğunun kolondaki boyuna donatının uzama miktarına bağlı olduğu görülmüştür.

Modeling Plastic Hinging Regions in Reinforced Concrete Bridge Columns

Examining the spread of plastic deformations at various stages of loading is a complicated problem for bridge structures under multi axial dynamic loading. A detailed three dimensional nonlinear finite element model of a bridge column was developed using the computer program ABAQUS and the model was compared with the measured displacement results along the column of a bridge system subjected to dynamic biaxial loadings in an earthquake simulator. The bridge system was subjected to a series of test trials with increasing earthquake intensities. Computer simulations were performed for complete trials in order to provide information about the variation in the spread of plasticity. According to the results, it was observed that changes in the length of plastic hinging regions on the bridge column depend on the strain in the longitudinal reinforcement.

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