Deriving Gaussian Fatigue Test Spectra from Measured non Gaussian Service Spectra

A well-known problem is the transition from measured random vibration service loads to synthetically generated test signals. They are used for experimental vibration tests modelling the fatigue potential of long-lasting real service loads within a limited test interval. The challenge of this transition is caused by the non-Gaussian character of the service loads and the fact that the fatigue loads that have to be kept for the tests are caused by the response vibrations of an arbitrary structure. The analysis presented here is based on the finding that the non-Gaussian character of the service load is a function of frequency.