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In Abaqus, how to get SSE in UMAT?

Submitted by yw5aj on
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ABAQUS
UMAT

Hi all,

 

I have been writing a UMAT function with modified hyper-visco-elastic model. My question is: after I got the Cauchy stress at the end of step, how do I get the SSE （elastic strain energy density)?

 

If it is only hyper-elastic I would have known (since the strain energy function itself is given). However, if it is viscoelastic, how should I calculate?

 

PS: I would also appreciate it if anyone could shed some light in getting SPD, SCD as well. Thanks a lot!

 

-Shawn

Bending stocky S4R beam

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bending beam S4R stocky deflection
Hello
I'm working on stocky S4R I-beam(nonlinear analysis). Span length is 1.7m and 0.5m heigth. Beam is simply spported and loaded at mid-span by concentrated force.

Unfortunately it looks like my beam is to stiff.
Deflection is smaller than I expected.
Critical load is higher than I expected.

Is this problem connected to bending and shearing stocky element?
Is it about timoshenko/bernoulli beam theory? In my case I use shell elements.

Why does abaqus show negative stresses?

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education

I have modelled a crack in a curved shell and I don't quite understand why abaqus shows negative stresses?



http://www.flickr.com/photos/85999516@N07/7879610130/in/photostream   [STRESS]      (8mm crack)

http://www.flickr.com/photos/85999516@N07/7879640092/in/photostream   [DISPLACEMENT]

Difficulties on analysis of fatigue short crack behavior

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short cracks

As an issue far from being settled, the analysis of short cracks has always many difficulties.

1, First of all, which method can be used to describe the short crack behavior?

how to mesh AC3D4 acoustic tetrahedral

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ABAQUS
meshing

im working on an abaqus model which should be meshed by AC3D4 acoustic tetrahedral elements.

 i attached the picture of main meshed model and my model .

but there is a difference between them. ( i pointed them by white areas)

  

how can i mesh o control mesh to create that kind of meshing

 

 top model is mine and bottom is original model.

 

tnx

 

 

Abaqus or COMSOL

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Hello 

 I am a freshman to iMechanica, I have a question and hope to get some help. I am currently having a project analyzing hydraulic fracture propagation path. And I would like to build up a finite element model use either Abaqus or COMSOL. I  am wondering which software would be more appropriate for this reservoir geomechanic research project. Thanks!

 

Weiwei

Solid/Fluid Mechacnics

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Plasticity

Hi,

In my research i am trying to develop a new model for plastic deformation, and i suspect there is a strong similarity between

plasticity and turbulent flow !.

My question is: if there is workd done trying to apply Reynolds decomposition (Reynolds Stress) to the governing equations and solved plasticity problem in Solids?

thanks,

Yaron B.S.

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