Research on Load Spectrum Construction of Bench Test Based on Automotive Proving Ground

The fatigue failure of automobile structures has drawn much attention recently in reliability and endurance design. Therefore, in order to predict the fatigue life accurately, complex variable-amplitude loads must be compiled into the appropriate load spectrum. The rain-flow counting method is adopted to extract the load cycles from the random loads. A statistical method based on the mixture distribution model is proposed to analyze the multimodality of load cycles. Meanwhile, the collected random loads are extrapolated to the full life of vehicles based on the Peaks-Over-Threshold model. Finally, the one- and two-dimensional load spectrums are compiled according to the load cycles and joint probability density.