Viking Systems has extensive knowledge and capability with fatigue of ships and offshore structures.

Fatigue loading in ships and offshore structures involves an in depth understanding of the day-to-day loads that occur throughout the life of the asset and includes an assessment of several parameters to properly assess the fatigue demand that can be expected and which needs to be designed for considering both the future demand and the past damage built up over time:

  • Wave scatter data (wave height and period probabilities)

  • Heading probabilities

  • Loading case probabilities

  • Vessel draft probabilities

The methods that are applied by Viking Systems range:

  • Spectral fatigue analysis using wave scatter diagrams and spectrums

  • Spectral fatigue using rms load ranges and probability of occurrence

  • Weibull distribution of design stress range

Damage ratios for four drafts for a side shell detail showing influence of drafts:

Spectral Fatigue Damage Ratios of an FPSO Topsides Stool: