In order to estimate a structure's fatigue life when excited with an acceleration profile the fatigue parameters must be known. However material's fatigue exponent and fatigue strength are not always ...readily available, especially for complex structures that include riveted or welded joints for which additional fatigue tests are needed. This study introduces a new fatigue-parameter assessment method based on random vibration loading and its application to a blind-hole rivet joint that diminishes the need for additional fatigue tests. The presented procedure requires a simple experimental setup; however, a more extensive analysis of the experimental results is necessary. The method of fatigue parameter assessment is presented and applied on real, experimentally obtained data from vibration tests of rivet-joint specimens, excited with a random base-vibration load in the frequency range of a single natural frequency. Special attention was given to the modelling of the rivet joint and the uncertainties arising from the riveting process were considered. With the presented procedure it is possible to obtain the fatigue parameters solely from the results of random-vibration testing with different acceleration profiles and therefore diminishing the need for additional classic fatigue tests. The obtained fatigue parameters indirectly include the stress concentration factor and the damping-loss-factor increase during the damage accumulation. Additionally, by applying the random-vibration load the influences of the natural-frequency shift and the small nonlinearities of the structure are reduced, which can present a major issue in classic harmonic-vibration fatigue testing. Keywords: vibration fatigue testing, fatigue parameters, random base-excitation, frequency-domain counting method Highlights * A method for fatigue parameter assessment from vibration tests with electro-dynamic shaker is presented. * The tested specimens were excited with acceleration-controlled random signal. * Frequency based Tovo-Benasciutti method was applied to the parametrized numerical model to determine expected fatigue life of a particular specimen. * The method was applied to actual testing of blind-hole rivet joint with nonlinear response.
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