The European research project FatHTS investigated the applicability of high tensile steel for different ship types, The focal point of the project was to increase the permissible design stresses in order to upgrade the efficiency of designs in the future. Since the fatigue strength of welded structures is nearly independent of the yield strength of the material, the proof of a sufficient fatigue strength becomes particularly important in cases where high-tensile steel is used. For this reason fatigue tests with representative details of ship structures were carried out. This paper describes the results of large-scale fatigue tests of three different bracket connections in frame corners. During the fatigue tests expected cracks as well as unexpected cracks were observed. These test results showed the necessity of fatigue tests in order to verify and improve fatigue strength calculations. The structural stress concept (hot spot concept) has been applied to predict the fatigue behavior of the specimens. Various methods exist for the calculation of structural stress at the hot spot (hot spot stress), Niemi (2001). Usually the finite element method is used for the hot spot stress calculation at design stage. The hot spot stresses resulting from a finite element analysis are influenced by the extrapolation scheme, the element type and the element size at the hot spot region. Additionally, the implementation or neglect of the weld and in the first case the size of the weld (actual or design dimensions) influence the calculated hot spot stresses.
Predicted and observed fatigue behavior of bracket connections
Prognostiziertes und beobachtetes Ermüdungsverhalten von Knieblechverbindungen
Ship Technology Research / Schiffstechnik ; 50 , 1 ; 14-22
2003
9 Seiten, 9 Bilder, 2 Tabellen, 11 Quellen
Aufsatz (Zeitschrift)
Englisch
Predicted and Observed Fatigue Behaviour of Bracket Connections
Taylor & Francis Verlag | 2003
|Predicted and Observed Fatigue Behaviour of Bracket Connections
Online Contents | 2003
|Fatigue Behaviour of Different Bracket Connections
British Library Conference Proceedings | 2001
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Kraftfahrwesen | 2001
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