Van Bölgesinde Yakın Saha Deprem Hareketlerinde Spektral Sönüm Parametresi, κ (kappa)

Abstract

Anderson ve Hough (1984) tarafından ilk kez kullanılmaya başlanan spektral sönüm parametresi, κ (kappa), birçok uygulamada gittikçe artarak kullanılmaktadır ve bir istasyonda kaydedilmiş kuvvetli yer hareketinin spektral alanda yüksek frekanstaki eğimini ifade eder. Geçtiğimiz son yıllarda, kappa tahmini ve deprem tehlike analizi sonuçlarına etkisi üzerine birçok yaklaşım geliştirilmiştir. Kappa’nın zemin koşullarına bağlı olarak, yüksek frekans aralığındaki yer hareketinde deprem tehlike değerlerinde 3 hatta zemine bağlı olarak 6 kat artış gözlemlenmiştir. Bu parametrenin önemi sebebiyle Van Bölgesi için κ tespit edilmeye çalışılmıştır. Bu çalışmada, κ tahminleri için Afet ve Acil Durum Yönetimi Başkanlığı Kuvvetli Yer Hareketi gözlem ağına ait (AFAD) Van bölgesindeki istasyonlarından alınan ivme-ölçer deprem kayıtları kullanılmıştır.

Keywords

• κ (kappa),stokastik simülasyon yer hareketi,GMPE’lerin (yer hareketi tahmin denklemleri) kaynak-hedef düzeltmeleri

The Spectral Decay Parameter κ (kappa) for the Near Site Events in Van Region

Abstract

The spectral decay parameter κ (kappa) is increasingly used in many applications since it is first introduced by Anderson and Hough (1984) and basically measures the decay of high-frequency ground motion amplitudes for each ground motion acceleration time history record at one location. During the past years, multiple approaches were developed for its estimation and effect on seismic hazard calculations, where it was observed that κ can have an impact in terms of 3 to 6 times increased seismic hazard values for high-frequency ground motions depending on the site conditions. In this study, the strong ground motion recordings from the Disaster and Emergency Management Authority (AFAD) stations in Van region are taken into account for κ evaluations.

Keywords

• κ (kappa),stochastic simulation of strong ground motion,host-to-target adjustments of GMPEs

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