Fastener Pull through failure analysis ABAQUS

[hertfordshirep]

Hi everyone.
I am trying to get load vs displacement graph in ABAQUS for pull through failure of bolted joints in composites. I am using two circular plates with a hole.The plates are joined together with a cohesive layer in between. There is a bolt in the hole. I am applying a displacement bundary condition on a reference point on the bolt. However I am getting linear curve not the required one. Could anyone guide me on this.
Kind Regards

 

[SWComposites]

Well, are you using linear material properties?

And why are you trying to do this with a FEM re just running a test?

 

[Composites_FEA_Guru]

Hi hertfordshirep,

As SWComposites mentions, if you are using linear elastic material properties, the only nonlinearity you would see in a load-displacement curve would be from nonlinear geometric effects or maybe a bit from contact nonlinearity.

Also as SW alludes too, this is a challenging simulation to undertake.

You'll want to look into a progressive failure analysis. This can be done within Abaqus by using the Hashin damage initiation and evolution material property characterization. However, with this type of analysis, where the stiffness of the composite material properties are reduced after failure initiates, you can often times run into convergence issues. If you get this far, I can provide some additional tips. There are 3rd party composite material specific software platforms that integrate with Abaqus that make this process more robust and efficient (HeliusFA, Digimat, Multimech, Genoa, etc.). Another issue is the type of information are you looking for in your load-displacement curve. Progressive failure can do a good job pinpointing peak/ultimate load but anything past that is a bit unreliable from simulation and is probably best left to testing.

Good luck.


Dan Milligan
linkedin.com/in/danmilligan/
Contact me through LinkedIn for additional discussion.