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The uncertainty in fatigue lifetime calculations brings up the necessity of experimental verification. Several efforts have been undertaken in the past to improve and introduce new test methods. An alternative method for variable amplitude loading using resonance test facilities is introduced and discussed. A comparison of test results on a resonance test facility with a new control system and a servo hydraulic test facility shows no significant difference in the test results. The compatibility of the test results to those results of accepted fatigue life tests is proven for three test series of different specimens. The introduced resonance test control offers a new way for fatigue life tests, reducing the cost and time, as well as increasing the safety of products because it permits testing to much longer lives in a relatively short time.

Current european standards for axle calculations (EN 13103 and EN 13104) are based on an analytical method applying flexural beam principle for critical sections selected by the designer. The method bases on works performed in the 1960s that were introduced to different international reports and recommendations before being adopted by the mentioned european standards. The present procedures for design, production and maintenance of axles lead to reliable products, as shown by the accumulated experience along the last decades. These methods are widely accepted and applied to axle designs in common usage. However, in order to look for optimized products, more accurate modelling techniques like the finite element analysis (FEA) should be adopted, especially for complex structures like powered axles. The characteristics of the finite element models to be applied to railway axles have been analysed in terms of element definition, convergence analysis, boundary conditions, etc. Parametric analyses have been performed to assess the applicability of the models. The numerical models generated have been validated through the comparison with experimental results coming from full scale fatigue tests. Finally, a methodology to design axles using modelling tools as a complement to current european norms is proposed looking for a compromise between the computational effort and the results obtained.

Torsional vibration is an oscillation phenomenon occurring at driven railway vehicle wheelsets. As the resulting dynamic stresses can be significantly larger than the maximum static motor torque, axle and press fit are at risk of failure. To prevent dangerous vibration events and with these, press fit and axle from failure, traction drive manufactures nowadays used to implement vibration suppression algorithms in drive controls. In this paper, the effectiveness of such suppression algorithms is analyzed. Furthermore, as a pilot survey, we analyze to what extend traction controls influence the excitation of torsional vibration.

KurzfassungFür die Auslegung von Radsätzen und deren sicheren Einsatz in Eisenbahnfahrwerken ist die Verifizierung der Dauerfestigkeit in der Berechnung und dem Versuch ein wesentliches Kriterium. Radsatzwellen werden nach den europäischen Normen EN 13103 und EN 13104 dimensioniert. Prüfungen und Messungen nach normierten Standards werden nur teilweise durchgeführt. Für eine Vergleichbarkeit der Ergebnisse aus Messungen, Versuchen und Berechnungen gemäß allgemeiner Richtlinien, wie z.B. FKM-Richtlinie, Euro-Codes etc., sind diese experimentellen Nachweise jedoch unumgänglich. Im Beitrag sollen verschiedene Prüfverfahren vorgestellt, Bewertungsmöglichkeiten aufgezeigt und ein Konzept einer innovativen Prüftechnik präsentiert werden.