Finding Dangerous Waves-Review of Methods to Obtain Wave Impact Design Loads for Marine Structures

Green water and slamming wave impacts can lead to severe damage or operability issues for marine structures. It is therefore essential to consider their probability and loads in design. This is difficult, as impacts are both hydrodynamically complex and relatively rare. The complexity requires high-fidelity modeling (experiments or CFD),...

Required test durations for converged short-term wave and impact extreme value statistics — Part 1: Ferry dataset

For the design of maritime structures in waves, the extreme values of responses such as motions and wave impact loads are required. Waves and wave-induced responses are stochastic, so such responses should always be related to a probability. This information is not easy to obtain for strongly non-linear responses such as wave impact forces....

Required test durations for converged short-term wave and impact extreme value statistics–Part 2: Deck box dataset

In the assessment of wave-in-deck loads for new and existing maritime structures typically model tests are carried out. To determine the most critical conditions and measure sufficient impact loads, a range of sea states and various seeds (realisations) for each sea state are tested. Based on these measurements, probability distributions can...

Prediction of short-term non-linear response using screening combined with multi-fidelity Gaussian Process Regression

Predicting wave impact design loads is crucial for ensuring safety and performance of maritime structures, but it is challenging due to the complexity and rarity of these events. Existing methods are mainly suitable for prediction of weakly non-linear responses, or are very computationally expensive. Highly nonlinear responses require a fidelity...

Generating an ensemble of mutually exclusive and exhaustive waves targeted for extreme responses

To examine the reliability or performance of marine systems related to dynamic time-varying responses, time domain simulation may be required. But for long durations, brute-force simulation is clearly not feasible from a computational point of view to examine converged extreme value statistics. An additional challenge is defining a set of...

Long-term rogue wave occurrence probability from historical wave data on a spatial scale relevant for spar-type floating wind turbines

Very large waves, such as rogue waves, can be dangerous for ships and offshore structures. There is no consensus on the theoretical occurrence probability of these rogues and ocean measurements containing rogue waves are rare. This paper addresses the long-term occurrence probability of rogue waves using time-extreme (TE) and space–time...

Design Contours for Complex Marine Systems

This paper examines the performance of 6 stiffened ship panel designs in different operational profiles. The main question of interest is: which sea states will lead to the worst panel performances in terms of reliability? As stiffened panel collapse is governed by combined lateral and in-plane loading effects (non-linear functions of the...

Numerical investigation of response-conditioning wave techniques for short-term rare combined loading scenarios

Response-conditioning wave techniques are a rational way to link wave excitation environments with return-period extreme loading responses. By retaining the wave excitation which leads to a design response, these techniques can also define extreme combined loading scenarios. For complex or novel hull forms, combined loading may be relevant...

Response-based reliability contours for complex marine systems considering short and long-term variability

Evaluating marine system reliability requires considering the interaction of a limit state with the stochastic ocean excitation. Given a range of operational profiles, a relevant question is which sea states lead to the worst-case system responses, considering the effects of short and long-term variability. If the identified subset of...