Anyone have structural analysis and seafastening experience?

[davidmay84]

We are using SACS to try to design our seafastening for a 4000mt module on a 350' barge.

Generally you load the module onto the barge and then fit/weld roll braces and other seafastening onto the module to the barge grillage.

The problem is, when you model this in SACS the roll braces are pre-loaded with a portion of the self-weight of the module, where they obviously cannot be because they are welded on after loadout. These braces should only take forces from roll, heave, pitch, etc.

Does anyone know how to model seafastening members in SACS where they resist sea-state induced forces but do not carry the self weight of the module?

If you need further information I can supply.

Thx, David

 

[Ussuri]

Never used Sacs, but can you model your seafastening steelwork independent of the main structure and then connect them using springs/couples? The spring/couples can be set with a stiffness in the direction you want to transfer the load?

 

[weab]

It has been a long time since I used SACS. Does it do temperature loading? How about a static load case that determines how much load the roll braces take. Then add temperature loads in your roll braces only which end up applying this load in the opposite magnitude. This may take a few iterations to make sure you apply a net zero load in your braces.