Sürekli Sistem Olarak Modellenen Yarı-Rijit Mesnetli Tek Katlı Çerçevelerin Tepki Spektrumları

Yıl 2006, Cilt: 7 Sayı: 2, 127 - 133, 05.08.2016

Oktay Demirdağ

Öz

Çerçevelerin dinamik analizinde, ankastre bağlı oldukları ve kolonlarının kütle ve deformasyonunun ihmal edildiği kabulleri sıkça yapılır. Ancak gerçekte, çerçeve kolonlarının temele bağlı noktaları sismik etkiler sebebiyle ötelenme ve dönme gösterebilmektedir. Bu durumda, mesnet davranışı elastik yaylarıyla modellenebilir. Ayrıca, gerçekte kolonlar yayılı kütleye ve rijitliğe sahiptir. Bu çalışmada, Timoshenko kolonu olarak modellenen çerçevenin mesnedi ötelenmeye ve dönmeye karşı elastik yaylar ile modellenmiştir. Genelleştirilmiş hareket denklemi sistemin enerji ifadeleri kullanılarak Lagrange denklemi ile elde edilmiş, Newmark-β metodu kullanılarak sistemin dinamik tepkisi hesaplanmış ve 1999 İzmit depremi yer ivmeleri kullanılarak tepki spektrumları elde edilmiştir

Anahtar Kelimeler

tepki spektrumu, timoshenko modeli, tek katlı çerçeve, yarı-rijit mesnet

RESPONSE SPECTRA OF SEMI-RIGID SUPPORTED SINGLE STOREY FRAMES MODELED AS CONTINUOUS SYSTEM

Öz

The assumptions of frame supports being fully rigid and distributed masses and deformations of the columns being neglected are frequently taken into consideration in dynamic analysis of plane frames. In practice, however, column bases of frames may usually rotate and translate a little due to seismic effects. In this case, support behavior can be modeled using elastic springs at the column bases of frames. Besides, columns, in fact, are not massless, and have distributed mass and stiffness. In this study, the support of the frame modeled as Timoshenko column is modeled by elastic springs against rotation and translation. The generalized equation of motion is obtained by Lagrange equation using energy relations of the system, the dynaimc response is computed for different elastic spring coefficients using incremental Newmark-β method, and response spectra are obtained using ground accelerations of 1999 Izmit earthquake

Anahtar Kelimeler

response spectrum, single-storey frame, semi-rigid support, timoshenko model

Kaynakça

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