Fatigue of welded joints under narrowband non-Gaussian loadings

Wind and structural modelling for an accurate fatigue life assessment of tubular structures

“…(13). From this item, it also indicates a nonlinear relationship between the forces and the wind velocity.…”

“…Because the frequency domain analysis cannot properly take the non-linear load effects, large deformation as well as the plasticity into account, and also because the power spectrum of the critical stress due to the dynamic wind loading may not be narrow banded initiated from the influence of the background components of incident turbulence [12], crosswind induced vibrations, wind directional effects and structural damping etc., the inappropriate use of frequency domain based spectral methods developed for Gaussian processes may then significantly underestimate the fatigue damage contribution [13]. While in the mean time, the spectral methods based on non-Gaussian process are still under development.…”

Fatigue damage assessment for a spectral model of non-Gaussian random loads

“…For mooring lines, for instance, loads often exhibit significant asymmetry having skewness about 0.8, see [1]. A serious consequence of not taking this into account in a fatigue application is that the fatigue life predictions from the model may be far too long, as reported by [2][3][4][5][6]. In order to overcome this problem a lot of effort has been made to find suitable non-Gaussian models.…”

Critical Evaluation of Frequency-Domain Approach for Fatigue Damage Estimation

“…For this reason, an alternative approach to lifetime prediction has been developed, which is based on the stress PSD [3,4,[7][8][9][10][11][12][13][14][15][16][17], On the other hand, the time-domain methods require each individ ual cycle to be counted from the stress history, the frequencydomain methods predict the probability density function of stress cycles from the stress PSD. Using the probability density function of stress cycles in combination with one of the conventional dam age accumulation rules and the material properties under cyclic loading the lifetime prediction can be made.…”