Corrosion-Fretting Fatigue Analysis of Bridge Cables Based on Multifactor Competition Model and Time-Dependent Reliability

Bridge cables are the safety lifelines of cable-supported bridges. However, many suspenders in cable-supported bridges were inaccurately evaluated and suffered from premature damage under complex environmental and load actions. A multifactor competition model was proposed and validated to consider the coupling effect of multifactor actions. Furthermore, a framework for corrosion-fretting fatigue analysis was established based on the competition model, stochastic finite-element method, and time-dependent reliability. The degradation process in the wires and suspenders of a bridge was analyzed, and their service lives were accurately predicted. In addition, the suspenders were quantitatively investigated for multifactor coupling and single-factor effects. This paper found that the coupling effect of corrosion, fretting, and fatigue significantly aggravates wire damage and reduces the service lives of short suspenders.