JCCRT Damage Initiation greater than 1

[DavidMcArthur]

Hi all,

I have set up a model of a cellular material modelled using B31 beam elements compressed by hard contact (penalty friction=0.3) defined with 2 analytical rigid surfaces. The material model I have proposed is taken from literature and includes: Elasticity, density, Johnson-Cook plastic hardening, Johnson-Cook damage and linear damage evolution with fracture energy criteria (screenshots attached). I have requested JCCRT, SDEG and STATUS in field outputs (I have applied antialiasing but this shouldn't affect results significantly it just removes noise.

In my results, JCCRT has a maximum value of ~19,000 (screenshots attached) - since I have introduced damage evolution, I don't understand why JCCRT is so high as it should reach a maximum of 1. I have attached the .cae file for consideration.

 

[FEA way]

Can you check the value without antialiasing ? Are you sure that the damage evolution criterion is properly defined ? Outputs related to damage initiation should be limited to 1 if that's the case. Otherwise, they can grow indefinitely.

 

[DavidMcArthur]

Hi there,

Thanks for your reply, I will check with no antialiasing but it really shouldn't affect it. I have included a screenshot of the damage evolution parameters. I have used the same parameters for a simulation with different geometry and JCCRT with antialiasing behaves as expected and is capped at 1.

Best,
David