Betonarme Baca Kesitinin Tekrarlı Yükleme Altındaki Davranışının Sonlu Elemanlar Metodu ile Modellenmesi
Bu çalışmada, betonarme bir baca kesitinin deneysel davranışına benzer sonuç verebilecek bir sayısal
model sunuldu. Daha önce yapılmış olan deneysel çalışmanın amacı, tekrarlı yüklere maruz kalan ve
geniş açıklıkları olan baca tipi yapıların deprem yükleri altındaki performanslarını değerlendirebilmekti.
Detaylı bir sonlu elemanlar modeli oluşturuldu ve bütün donatılar direkt olarak çubuk elemanlar ile modellendi. Baca kesitinin beton cidarı hacim elemanları ile modellendi. Donatı malzemesi için bilineer
bir malzeme modeli kullanıldı. Beton malzemenin çok-eksenli gerilmeler altındaki davranışını ve donatı
sargılama etkisini modellemek çalışmada önemli bir adım teşkil etti. Baca kesitinin beton cidarını için
ticari bir yapısal çözüm programı olan LS-Dyna’daki Winfrith modeli kullanıldı. Sonlu elemanlar
analizinde elde edilen taban momenti-yer değiştirme sonuçları ve betonda oluşan çatlaklar daha önce elde
edilen deneysel sonuçlarla karşılaştırıldı.
Finite Element Modeling of Cyclic Behavior of a Reinforced Concrete Chimney Section
In this study, a numerical model was presented to simulate the experimental behavior obtained for a
reinforced concrete chimney section. The purpose of the previous experimental investigation conducted
for the chimney section was to evaluate the effect of large openings on the cyclic response in order to
reveal the performance of such structures under seismic loads. A detailed finite element model of the
chimney section was constructed and all of the reinforcements of the chimney were directly taken into
account by line element representations. The volume of the concrete chimney shell was modeled with
hexahedral elements. A bi-linear material model was used for the reinforcements. A crucial step in the
finite element approach was to employ a constitutive material model that took the multi-axial state of
stress and confinement effects in concrete into account. The Winfrith concrete material model of the
commercial LS-Dyna structural code was chosen for the shell of the chimney section. Comparisons of the
results of the finite element study with the experimental measurements showed a good agreement for the
base moment-displacement response and crack formations around the opening regions of the chimney
section.
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