Performance of large-scale fatigue tests

The fatigue strength for the design of steel structures is generally determined experimentally by fatigue tests. Because the results of fatigue tests usually have a large scatterband, there is a larger number of tests for every construction detail required. For cost reasons, the fatigue tests are therefore performed generally with small-scale specimens. In recent years there were performed several large-scale fatigue tests for the examination of the size-effect on the fatigue strength of welded steel structures at the University of Applied Sciences Munich. Especially the resonance testing system using attached external vibrators is an appropriate and cost-effective method for performing fatigue tests with large-scale specimens. With this method large-scale fatigue tests with specimen dimensions comparable to real structures up to 18 m girder lengths and weights up to overall 20 tons were carried out in different research programs. Within this paper the test set-up of these large-scale fatigue tests is shown. The paper summarizes the obtained results for the typical construction detail of the transverse stiffener welded on plates and rolled sections (HISTAR-profiles) with flange thicknesses up to 100 mm and for the construction detail of welded K-joints made of hollow section profiles with wall-thickness up to 60 mm. © 2019 Ernst & Sohn Verlag für Architektur und technische Wissenschaften GmbH & Co. KG, Berlin.