keeping constant stress over elements

[hasan2]

Hi,

I am working on mechanical modeling of the contraction of the muscle. I am using ABAQUS software and I need to keep a constant initial stress over the elements of the structure. There is an instruction *prestress hold. But when I use this instruction the stress changes through the element. It would be very helpful if anyone suggest me any method or give some useful tips to use this instruction to keep the stress constant over the element.
Thank you

 

[IceBreakerSours]

Look up "*initial conditions, type=stress" in the documentation.

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[hasan2]

Thank you IceBreakerSours for you reply.

Actually I have used "*initial conditions, type=stress" to apply stress to the structure and then I used "*prestress hold" to keep the stress constant, but "*prestress hold" does not work properly and stress changes over the elements during the simulation. I am wondering if it is normal, I meant the stress should change during the simulation because of the mechanical equilibrium equations, or there is something wrong with my simulation. I would appreciate it if anybody guides me through this.

Thank you

 

[IceBreakerSours]

Questions: Standard or Explicit? Type of analysis? Material models?

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[hasan2]

Thank you for the reply.

My simulation is standard, the analysis is static, and the material model is 2-dimentional (2D) linear elastic isotropic material with a definite Poisson's ratio and Young's Modulus. Actually I am performing 2D plane stress analysis and then I am going to consider a more complex 3D analysis.

Thank you

 

[DrBwts]

I'm confused. Are you putting a constant stress applied to all the nodes of your model in just 1 time step?

If that is the case then you will see a difference otherwise why bother modelling it at all?