material shear due to bolt load 1

[amwc]

Hi
When using abaqus to check if an element is failing in shear what's the check that you need to carry out as I am assuming that the program will not tell you it is failing?

I am trying to find the maximum load on a single bolt single shear assembly in a brittle material.

Many thanks

AM

 

[FEA way]

Check the stress output and compare it with allowable values. Take a closer look at the deformed shape of the model. And finally, you can use the shear damage criterion to model the actual failure, including element deletion.

 

[amwc]

Hi This is my stress output
the element is a 250x250x30mm piece of glass with a 16 mm bolt in the centre. The glass is loaded with 1kN of force
Does this look about right?

 

[FEA way]

For brittle materials we generally use other failure criteria than the von Mises one. To obtain accurate stresses you should significantly refine the mesh around the hole. Then I would use the aforementioned shear damage initiation criterion (together with damage evolution).

 

[amwc]

Hi thanks for the reply

What it shear damage initiation criterion?

Also what criteria would you recommend?

Also I only have student edition 1000 nodes

Many thanks

 

[FEA way]

Actually, this shear damage criterion is still meant primarily for ductile metals (as all the basic damage criteria in Abaqus). If your brittle material is completely different than such a typical case (for example if it's concrete or composite) then it might be better to use some specialized material model available in Abaqus. Can you say what kind of material it is ?

 

[amwc]

element is a 250x250x30mm piece of glass with a 16 mm bolt in the centre

I’ve fixed the bolt hole and applied the load to one face of the glass

Thanks

I am just trying to see if the connection is safe

 

[FEA way]

Abaqus has a brittle cracking model that can be used for concrete, rocks but also ceramics. However, it’s available only in Abaqus/Explicit. Thus, I would use a standard material model in this case and evaluate failure based on stress output, as I’ve mentioned before. You should be able to do this using principal stresses.

 

[amwc]

Thank you very much,

How much do you think this would cost to have it done professionally?

AM