PSI - Issue 57

Kashif Kamran Toor et al. / Procedia Structural Integrity 57 (2024) 772–784 Author name / Structural Integrity Procedia 00 (2019) 000 – 000

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Fig. 2. (a) Global model; (b) Jacket substructure (c) Local pile sleeve model.

The following sections describe the fatigue methodology using the influence factors technique. Different weld modelling techniques are described and compared with the results from a detailed solid FE model including the cope hole detail based on the effective notch stress method.

Nomenclature DFF

Design Fatigue Factor Degrees Of Freedom

DOF

FE

Finite Element

FEA HSS INF

Finite Element Analysis

Hot Spot Stress

Influence Factors MPC Multi Point Constraint SCF

Stress Concentration Factor

2. Fatigue Analysis Methodology 2.1. General

The focus of this study is to highlight the effect of hot spot stress calculation on the fatigue life. Hence, only the major steps of the fatigue calculation procedure are described in this section. A deterministic fatigue analysis approach is applied to calculate the global load effect in the substructure. Environmental load input is based on the wave scatter diagram of annual wave distributions. A plot of the annual wave distributions is shown in Fig. 3.