Uncertainties in the fatigue design of offshore steel structures

摘要: Fatigue is one of the failure mechanisms offshore steel structures, which must be more carefully examined during design stage. It demonstrates many aspects uncertainty, due to stochastic nature wave motion, considerable dispersion physical and mechanical characteristics govern phenomenon, microscopic way in it initially develops. The deterministic analyses are most commonly performed call for safety coefficients, able only a very empirical combine uncertainties relative various factors that determine occurrence phenomenon. suitable tool quantify actually influence collapse structure calibrate respective coefficients probabilistic reliability analysis. widely used method carrying out fatigue analysis structures Wirsching represents an extension case well-known linear accumulation laws damage, wither Miner's rule, based on S-N curves, or Paris' law, fracture mechanics. purpose this study discuss what extent present approaches distinguish between different uncertainty contributions codes, from practical point view. conclusion advantages, terms increase usage factor, can obtained by improving quality inspections.