DAMAGE RISK ASSESSMENT OF REVETMENTS IN UK

Abstract

ABSTRACT

The Reliability-based design and risk assessment model REBAD (1), which is used to predict the reliability levels of coastal structures that are subject to high damage risk and vast capital expenditures, was implemented to Wiseman’s Bridge revetment in UK by utilizing Van der Meer failure functions. The failure mode probabilities were calculated by the Second Order Reliability Method (SORM), where the failure surface was approximated by a quadratic polynomial having the identical curvature at design point. In this study, a methodology was suggested to determine the lifetime damage probability of coastal structures, which are subject to large tidal ranges and storm surges. As a result, REBAD was successfully implemented to a rubble mound revetment subject to large tidal ranges as a risk assessment study in order to point out the necessity for the development of deformation-based design (DD) methodology instead of the partial safety system used in EU countries.

Keywords

• Key Words: Acute toxicity; Revetment, stability, limit-state, reliability, risk, uncertainty.

İNGİLTERE’DEKİ KIYI ANROŞMANLARININ HASAR RİSKİ ANALİZİ

Abstract

Maliyeti ve hasar riski yüksek kıyı yapılarının güvenirlik seviyelerinin tahmininde kullanılan REBAD (1) risk değerlendirme ve tasarım modeli, Van der Meer yıkım fonksiyonları kullanılarak, İngiltere’de Wisemen’s Bridge kıyı tahkimat yapısına uygulanmıştır. Yıkım modu olasılıkları, tasarım noktasında yıkım yüzeyinin eş eğriliğine sahip ikinci dereceden bir polinom kullanılarak İkinci Mertebeden Güvenirlik Metodu (İMGM) ile hesaplanmıştır. Bu çalışmada, yapının tasarım ömrü içindeki hasar olasılıklarının hesaplanmasında, yüksek gelgit seviyesini ve fırtına kaynaklı su kabarmalarını hesaba katan bir yöntem önerilmiştir. Sonuç olarak REBAD modeli, yüksek gel-git aralıklarının etkisi altındaki bir taşdolgu kıyı yapısına başarıyla uygulanmış, AB ülkelerinde kullanılan kısmi güvenirlik katsayıları yönteminin yerine deformasyona dayalı tasarımın (DT) kullanılması önerilmiştir

Keywords

• Kıyı tahkimatı, stabilite, limit durum, güvenirlik, risk, belirsizlik

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