T-Birleşimli Borusal Kaynaklı Çelik Yapının Yorulma Analizi

Servis ömürleri içerisinde tekrarlı yüklere maruz kalan çelik birleşimlerde yorulma hasarları meydana gelmektedir. Çelik iskeletli yapıları oluşturan kafes boru şeklinde yapıların tasarımı belirli yönetmeliklere göre gerçekleştirilse de bu yapılardaki en kritik yorulma hasarının belirlenmesine yönelik değerlendirmeler kısıtlıdır. Dahası, kafes yapıların ayrık geometrik konfigürasyonları yorulma hasarının doğru bir şekilde tahmin edilmesini zorlaştırmaktadır. Bu çalışmada düzlemsel T-birleşim örneği üzerinde iki farklı yöntemle ve farklı sınır ve yükleme koşullarında yorulma analizleri gerçekleştirilmiştir. Üç boyutlu sonlu elemanlar modelleri ve üç boyutlu kaynaklı birleşim detayı daha gerçekçi analizler gerçekleştirmek için oluşturulmuştur. Sonuç olarak sabit tipli mesnetlemenin rijitlik artışı sebebiyle yorulma ömrünü artırdığı tespit edilmiştir.

Anahtar Kelimeler:

yorulma, rüzgar türbini, kafes yapı, T-birleşim, Sonlu elemanlar modellemesi

Fatigue Analysis of Welded Tubular Steel T-Joints

Fatigue damage occurs in steel joints exposed to repeated loads during their service life. Even if the design of lattice tubular structures that make up the steel skeletal structures is carried out according to certain regulations, the evaluations for determining the most critical fatigue damage in these structures are limited. Moreover, the discrete geometric configurations of trusses make it difficult to accurately predict fatigue damage. In this study, fatigue analyzes were performed on the planar T-joint sample with two different methods and under different boundary and loading conditions. Three-dimensional finite element models and three-dimensional welded joint detail were created to perform more accurate analysis. As a result, it has been determined that the fixed type support increases the fatigue life due to the increase in rigidity.

Keywords:

Fatigue, Wind turbine, Lattice structure, T-joint, Finite element modeling,

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