In fatigue analysis should we consider gravity loads viz equipment loads, piping loads etc in SACS model while running it for seperate sea state.
For fatigue analysis, excitation source come from wave only.
Gravity loads are used for generated dynamic masses during eigen value analysis which create dynamic characteristics of platform i.e. Mass matrix, Mode shape matrix etc....
Gravity load will be used for superelement generation and eigen value analysis only.
1) Superelement - you need both gravity in sacs model and env in seastate file
2) Eigen valuw - you need only gravity in sacs modwl file.