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

Year 2019, Volume: 25 Issue: 6, 643 - 654, 25.11.2019

Gökhan Özdemir , Beyhan Bayhan

Abstract

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.

Keywords

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

Abstract

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 0^o to 180^o with increments of
10^o. 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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