Mode-{I, III} multiaxial fatigue of welded joints in steel maritime structures: Effective notch stress based resistance incorporating strength and mechanism contributions

The response of maritime structures can be multiaxial, involving predominant mode-I and non-negligible mode-III components. Adopting a stress distribution formulation based effective notch stress as fatigue strength parameter for mixed mode-{I, III} multiaxial fatigue assessment purposes, a mode-I equivalent von Mises type of failure...

Fatigue analysis and design of arc-welded and laser-welded lap joints: Toe vs. root induced failure

Fatigue might be the governing limit state in marine structures mainly induced by the waves and wind. Therefore, using a lap joint for the shell plating to replicate the appearance of a riveted joint for a retro yacht is critical due to the limited fatigue resistance. For this joint type cracks initiated at the root, which should always be...

The Effective Notch Stress Approach for a Tubular Joint

Offshore wind energy production is increasing rapidly and optimising the design of support structures has the potential to significantly reduce steel and costs. Jacket structures are commonly selected for deeper waters, and the design of these structures is primarily influenced by the fatigue performance of the tubular joints. The fatigue...

Mode-III fatigue of welded joints in steel maritime structures: Weld notch shear stress distributions and effective notch stress based resistance

The predominant mode-I response of maritime structures can be multiaxial, involving out-of-plane mode-III shear components. Semi-analytical mode-III notch stress distribution formulations have been established for critical details like welded T-joints and cruciform joints, reflecting (non-)symmetry with respect to half the plate thickness....

Effective Notch Stress Concept Investigations for Mode-III Loading & Response Conditions

Fatigue strength is typically a governing limit state for marine structures. Predicting an accurate fatigue lifetime is important for structures (e.g. wind turbines) that are supposed to be out at sea for decades. It is valuable for all type of structures that encounter stochastic sea loadings to optimise the design so that fatigue failure is...

Fatigue damage accumulation in steel welded joints, subject to (random) variable amplitude loading conditions: An improved fatigue-life model for naval ship structural design

The current fatigue assessment methods for naval ships are intentionally conservative. This is in part due to uncertainties in the fatigue capacity (i.e. fatigue resistance) of the ship: the nominal and hot spot structural stress incorporate implicit conservatism due to the inherent data-scatter and the Linear Damage Accumulation Model (LDAM) by...

Mid- and High-Cycle Fatigue of Welded Joints in Steel Marine Structures: Effective Notch Stress and Total Stress Concept Evaluations

The characteristic far field response spectrum of welded joints – the governing fatigue sensitive locations in steel marine structures – is predominantly linear elastic, meaning mid- and high-cycle fatigue (MCF and HCF) is most important for design. Using the effective notch stress- and the total stress concept, involving respectively S<sub>e...

Improvements for the prediction of the fatigue life of the deck plate in orthotropic steel decks: A design optimization study

Fatigue is an important issue for orthotropic steel deck (OSD) bridges and therefore a design criterium. Cracks will initiate at several locations of the bridge deck. It is likely that a crack at the trough web to deck plate joint at the crossbeam will initiate first. This crack initiates at the weld root and propagates through the deck plate. A...