In this study a method for calculating damage under impulse and harmonic loads, which shows that the two loads are equivalent. For each harmonic load an impulse load can be defined that generates an equivalent amount of damage. The analytical process was experimentally validated through the development of a testing procedure, which enables the determination of the Wöhler curve coefficients for both load types. \\
Within this work, a methodology for assessing damage with spectral counting methods for impulse loads, which are non-stationary and non-Gaussian. This challenges the basic assumptions of spectral methods, which predict significantly too long time to failure for structures subjected to these loads. The proposed analytical correction factor, which compares the fatigue life predictions between two frequency domain counting methods (Tovo- Benasciutti and narrowband) and rainflow counting method, can be analytically determined for a given dynamic system. The impact of impulse loads on the structures durabilty and the prediction of the lifetime with spectral methods was also expreimentally verified.
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