Page 404 - Marine Structural Design
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380 Part III Fatigue and Fracture
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Figure 20.1 Space Frame Model for a TLP
Fine FEA Model
A fine FEA model may be used to analyse the hull structure or a part of the hull structure in
detail. All relevant structural components shall be included in the model. In the fine FEA
model, major primary structural components are fully modeled using three- and four-node
platelshell elements and solid elements. Some secondary structural components may be
modeled as two-node beam elements.
Design Loading Conditions
To adequately cover the fatigue environment, fatigue design loading conditions consist of
cyclic environmental load components at a sufficient number of wave frequencies. These
loading conditions include:
Other cyclic loading
The loading components are either explicitly generated or interfaced from the global motion
analysis. Load summaries are made for each design loading condition and checked for
accuracy and load imbalance.
