Probabilistic model of fatigue damage accumulation of materials based on the principle of failure probability equivalence

Abstract

Fatigue damage accumulation model plays a critical role in life prediction and anti-fatigue design of material. It is still a challenging issue to accurately quantify its development process and probabilistic characteristics. In this study, a probabilistic model of fatigue damage accumulation is presented based on Weibull distribution and reliability analysis theory. Firstly, the general rule of fatigue damage accumulation is analyzed, and three basic assumptions about fatigue life and fatigue damage are drawn. Subsequently, two typical fatigue reliability analysis models are elaborated, and a probabilistic model of fatigue damage accumulation is proposed based on the principle of failure probability equivalence. Finally, three sets of experimental data of aluminum alloy are utilized to verify the proposed model. The results show that the proposed model is capable of quantifying the dynamic probability characteristics of fatigue damage accumulation. Moreover, the proposed model has high calculation accuracy, and it can be easily established based on fatigue life data of material.