Abstract
Fatigue is one of the major factors that may influence the safety of civil and marine structures. The presence of significant uncertainties related to loads, geometry, and material properties affects our ability to reliably predict the time-dependent performance of structures under fatigue deterioration. Probabilistic approaches can aid in predicting the time-dependent performance of structures under fatigue deterioration considering uncertainties. Moreover, reliability and risk-based management techniques can be used to predict the safe service life of fatigue sensitive structures, plan for their future inspections and support the decision-making process regarding maintenance and repair actions. This paper applies a probabilistic approach to quantify the reliability of a box-girder bridge against fatigue failure. The approach establishes a relationship between the maximum live load that can be sustained and the crack size. This relationship is next used to compute the time-variant bridge reliability against fatigue failure. The approach is applied to an existing steel box-girder bridge.