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.