Fatigue lifetime estimation of commercial vehicles

A computational procedure for the analysis and design of commercial vehicles structures is the main objective of this work. Random fatigue analysis due to the effect of rough pavement surfaces is carried out in the time domain based on Wöhlerʹs curves (stress levels vs. number of cycles), the Palmgreen–Minerʹs rule to compute the cumulative damage and the rainflow method for cycles counting. First-order reliability method (FORM) and Monte Carlo simulation with importance and adaptive sampling (MCSIAS) are used to evaluate the reliability index, which may be employed as a constraint in the weight optimization process. The structural weight optimization is performed using Farkas’ method with discrete variables.