A Fatigue Life Prediction Model of Stud Based on Damage Mechanics

ABSTRACT This study investigates the fatigue life of studs in steel‐concrete composite beams through an analysis of their fatigue damage mechanism based on damage mechanics theory. A fatigue life prediction model based on damage mechanics is derived, incorporating the service conditions of studs and the influence of fatigue stress ratio. Seventy‐two sets of stud fatigue test data from domestic and international sources were collected. MATLAB software was utilized to fit the relevant parameters of the fatigue life prediction model. The proposed prediction model was verified using another 20 sets of fatigue test data and compared with the typical models. The results indicate that the proposed damage mechanics‐based model exhibits high accuracy and stable predictions across varying fatigue stress amplitudes. Furthermore, the fatigue stress ratio significantly affects the fatigue life of studs. An increase in the fatigue stress ratio from 0.3 to 0.7 reduces the fatigue life of studs by approximately 50%.