Döndürülmüş yer hareketleri için hesaplanacak ortalama sönüm azaltma katsayısının kestirimi için yeni bir yaklaşım

Bu çalışma, sönüm azaltma katsayısının, yer hareketinin yönüne bağlı değişimini incelemektedir. Bu amaçla, seçilen orijinal yer hareketlerinin, birbirine dik yatay bileşenleri, maksimum yer hızlarına göre gruplandırılmış ve bu yatay bileşenler, 0°’den 180°’ye kadar, 10°’lik artımlarla döndürülmüştür. Orijinal ve döndürülmüş kayıtlara ait sönüm azaltma katsayıları, %10, %20 ve %30 sönüm oranları için hesaplanmıştır. Daha sonra, sönüm azaltma katsayısındaki değişimi, yer hareketinin yönüne bağlı olarak hesap etmek amacıyla, basitleştirilmiş yeni bir yöntem önerilmiştir. Sonuçlar, yer hareketi yönünün, sönüm azaltma katsayısının hesabında önemli bir parametre olduğunu ve bu çalışmada önerilen yöntemin, periyot ve sönüm oranından bağımsız olarak, sönüm azaltma katsayısını ortalama bazda hesaplanması bakımından oldukça başarılı olduğunu göstermiştir.

Anahtar Kelimeler:

Sönüm azaltma katsayısı, Yer hareketinin yönü, Döndürülmüş kayıtlar, Basitleştirilmiş Analiz yöntemi

A new approach for estimation of damping reduction factor of oriented ground motion records in an average sense

This study investigates the dependence of damping reduction factor on ground motion orientation. For this purpose, orthogonal horizontal components of selected as-recorded ground motions, clustered according to their peak ground velocity values, were rotated from 0o to 180o with increments of 10o. Damping reduction factors of all the rotated and original records were computed for damping ratios of %10, %20 and %30. Then, a new simplified method is proposed to estimate the variation in damping reduction factor due to ground motion orientation. The results indicate that ground motion orientation is a significant parameter in computation of damping reduction factor and proposed method is quite satisfactory in estimating damping reduction factor in an average sense regardless of the period and damping ratio.

Keywords:

Damping reduction factor, Ground motion orientation, Rotated ground motions, Simplified method of analysis,

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