A deterministic algorithm for nonlinear, fatigue‐based structural health monitoring

The irregularity of peak and valley stress values loading histories is the main impediment for accurate fatigue-based structural health monitoring. Since available fatigue material data (e.g., S-N curves) have been derived by cyclic tests, existing damage accumulation models can be implemented on structures under loading, cycle-counting algorithms transformation a spectrum into an equivalent one are necessary deterministic estimation life prediction. four inherent disadvantage; sequence cycles unknown, effect prediction cannot accounted (linear summation). present work proposes new algorithm containing two modules: summation algorithm. Unlike methods, proposed takes account has solid physical base because it simulates nonlinear with multi-linear procedure. With aid concept inserting fictitious in irregular spectrum, cycle counting module counts that correspond to loops easily applicable engineering practice. According author's knowledge, carried out first time. high-low two-stage random low-high decreasing amplitude multi-stage increasing alternating examined discussed.