Time-variant Reliability under Corrosion-caused Strength Degradation for Floating Structures in the South China Sea

This paper presents an approach for calculating the time-variant reliability of floating structures under corrosion deteri-oration. Based on in situ corrosion measurement data in the South China Sea, a corrosion prediction model is established. Ultimate strength under discrete stochastic extreme load events for the large floating structures is chosen as the time -dependent limit state. An effective method for time-variant reliability assessment subjected to corrosion deterioration is established based on conditional probability theory. The estimation of instantaneous failure probability for a typical float-ing structure is calculated by the first-order reliability method. Results show that severe corrosion deterioration degrades ultimate strength and reduces time-variant reliability over time.