Effects of cable-beam related vibration on cable fatigue reliability of cable stayed bridge under wind and train action

Taking a real cable-stayed bridge as the study object, effects of cable-beam related vibration on cable fatigue reliability of the bridge under wind and train action were analyzed. A 3-D precision finite element (FEM) model of a long span railway cable-stayed bridge was established by using the existing finite element dynamic analysis program, vibration responses of the full bridge under wind and train action were calculated, and characteristics of cable-beam related vibration of the full bridge were analyzed. The probability model of train traffic load was established, and the wind load probability model of the bridge was established according to wind speed statistical data at the bridge position, and the stress spectrum of the cable was calculated. Based on the damage theory, the fatigue reliability analysis of cable under wind and train dynamic action was performed by using Monte Carlo method. The results showed that in daily operation state of the bridge, cable-beam related vibration under action of wind and train can't cause cable resonance, and cable-beam related vibration is the main reason for the decline of cable fatigue reliability; for the fatigue failure probability of cable under long-term dynamic load, wind field action accounts for a smaller proportion, while train action takes a larger proportion; cable force of each cable in finished state affects cable stress amplitude under train action, and further affects cable fatigue reliability of the bridge under long-term dynamic action. © 2021, Editorial Office of Journal of Vibration and Shock. All right reserved.