How to apply weak springs in bolted composite single lap joint

[msuhairil]

Hi,
Currently i faced convergence problems in my FE Model. Both plates are made of CFRP and bolt from Titanium. The analysis using 3D solid element. I have read several publication mentioned that weak springs can be used to bolt and plates in order to eliminate rigid body motion and convergence problem. Where to apply it?..the whole surface of bolt and nut?or only at one node both at bolt and nut surface?

Any opinions are appreciated.

 

[Mustaine3]

Usually some random nodes at the part are used, that might have rigid body nodes.

If multiple parts can move, then the stabilization option in the step menu might be a better approach.

 

[msuhairil]

Thanks Mustaine3
What are rigid body nodes?degree of freedom? I have no idea

 

[Mustaine3]

Typo. I meant rigid body modes.