Fatigue damage of materials and structures assessed by Wöhler and Gassner frameworks: recent insights about load spectra for the automotive

Neglecting any sequence effect of the load time history, thus accepting the Palmgren-Miner's rule as an assumption, we focus on the dual representation of high cycle fatigue behaviour expressed by Wöhler & Gassner, respectively. This necessary calls for the use of load spectra (in terms of amplitude, not frequency), which are here discussed with particular attention to the automotive field.