An Alternative Recommendation for Design Eccentricity

Öz

In this study, a new recommendation for the design eccentricity is proposed. One-story; three-story; and five-story elastic systems with all the same slab, column, beam sizes, and their orientations in the plane were investigated according to the Turkish Earthquake Building Code (TEBC-2018) by Response Spectrum Analysis (RSA). The obtained results are compared with the TEBC-2018 design parameters. The results showed accidental eccentricity is proportional to torsional stiffness and rotational response. If the rotational response increases, it leads to an increase in accidental eccentricity instead of translational stiffness and response in the direction where the earthquake strikes the structure. In addition, the proposed method was approximately the same as RSA for a single-story building by considering the effect of the accidental eccentricity. At the same time, it was found to be approximately 12-15% less for three- and five-story buildings. However, it was revealed from the results that the proposed method was more successful in estimating the additional (accidental) eccentricity effect than the current earthquake code.

Anahtar Kelimeler

• Torsional irregularity
• accidental eccentricity
• center of mass (CM)
• center of rigidity (CR)
• Turkish Earthquake Building Code (TEBC).

Tasarım Eksantrikliği İçin Alternatif Bir Öneri

Öz

Bu çalışmada, burulma düzensizliğini yeniden dikkate almak için frekans oranı ve etkili dönme yarıçapı tanımını içeren alternatif tasarım eksantriklik formülü önerilmiştir. Bu amaçla, aynı kat planı ve yapı elemanlarına sahip bir, üç ve beş katlı binaların iki yönlü burulma etkisi altında deprem yer hareketinin çift yönlü spektrum analizleri yapılarak yukarıda adı geçen binalar Türkiye Bina Deprem Yönetmeliği (TBDY-2018) tasarımına göre incelenmiştir. Bu çerçevede, elde edilen sonuçlar, TBDY-2018 tasarım parametreleri ile karşılaştırılmıştır. Karşılaştırılan sonuçlara göre, ek dışmerkezliğin her bir kattaki burulma rijitliği ve dönme ile doğru orantılı olduğu saptanmıştır. Bir başka deyişle, yapının plandaki burulma etkisinin çoğalması depremin yapıya etkidiği yöndeki ek dışmerkezlikte bir artışa neden olmuştur. Ayrıca, önerilen yönteme göre ek dışmerkezlik etkisi tek katlı bina için spektrum analiz sonucuyla neredeyse aynıyken bu durum üç ve beş katlı binalarda ise yaklaşık olarak %12-%15 arasında daha az bulunmuştur. Sonuç olarak önerilen yöntem ek dışmerkezlik etkisini tahmin etmede mevcut yönetmeliğe göre daha başarılı olduğu görülmüştür.

Anahtar Kelimeler

• Burulma düzensizliği
• ek dışmerkezlik
• kütle merkezi (KM)
• rijitlik merkezi (RM)
• deprem yönetmeliği TBDY-2018

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