Methiod for counting fatigue damage in frequency domain applicable to multi-spectral loading pattern

摘要

The present invention relates to a method of calculating fatigue damage in a frequency domain for vibration testing of a mechanical system. According to the present invention, a strain gauge is attached to measure fatigue damage in a time domain, Conventional methods for calculating fatigue damage using a zero-crossing peak count method are accurate, but for a mechanical system with an irregular random signal, a large amount of time-domain data However, the conventional methods of calculating in the frequency domain to solve such a difficulty have solved the problems of the conventional methods of calculating fatigue damage which have limitations applicable only to harmonic excitations, Utilizing acceleration data in a condition with sine-on-random (SOR) representing the spectrum We propose a method to calculate the fatigue damage degree in the random excitation state and calculate the fatigue damage degree in the random, harmonic and SOR excited state in connection with the fatigue calculation method in the existing harmonic excitation state. There is provided a method of calculating a fatigue damage degree in a frequency region capable of coping with a variety of vibration spectrum patterns configured to be capable of both.