Abschlußbericht EUR 14316 DE

Corrosion fatigue of welded steel nodes and cast steel hybrid nodes at component similar scale

Abstract
This project was carried out as part of a common programme of the European Coal and Steel Community in the field of corrosion fatigue of offshore structures and was coordinated by the Verein Deutscher Eisenhüttenleute (VDEh). In this project eleven welded tubular joints (K-joints) made of the fine grain structural steel StE 355 were tested. The tests were conducted, with one exception, in artificial seawater, in part under free corrosion conditions, in part under cathodic protection. One test took place in air. Furtheron four welded tubular joints made of the high-strength fine grain structural steel StE 690 with post-weld treatment by shot-peening or profile reinforcement and subsequent TIG-dressing and four hybrid nodes made of StE 355-steel with a cast steel insert of GS-8 Mn 7 were tested. In addition some 20 V-shaped cast steel specimens were included in the investigations in order to link up with the previous investigations with V-shaped welded specimens. The tubular joint tests were conducted under variable amplitude loading using the so-called Common Load Sequence (COLOS). The axial loading (Ris = -1) of the two braces was conducted in antiphase. Four tubular joints were tested under constant amplitudes, one of them after interruption of a variable amplitude test.